PMIP 2 Proposed Analyses

This page lists the analyses of the PMIP2 coupled ocean-atmosphere and ocean-atmosphere-vegetation simulations for 6ka and LGM that have already been proposed.

You can now use the database without having to submit a project!

For each proposed analysis, please get in touch with the listed contact if you need more information about the analysis, or if you are planning something similar!

Note: when you publish a paper related to your project, don't forget to send the reference to the webmaster! Your paper will then be listed in the Published Papers section, with a link pointing to it from your your project below (format of the link: [ month/day/year when the paper was published ]).

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Additions and changes should be sent to the webmaster in a similar format (people, aim, method, ...) as plain text (but feel free to attach a pdf of a proposed analysis to show any additional formatting to be applied, subscripts, etc...).

BIOME4 simulations

People involved: Sandy P. Harrison

Contact: Sandy P. Harrison

Aim

We plan to make offline simulations with the BIOME4 equilibrium biogeography-biogeochemistry model using climate output from the 6ka and 21ka ocean-atmosphere and ocean-atmosphere-vegetation models at 0.5° resolution. The BIOME4 simulations will be run using the anomaly procedure used in previous diagnoses of this type, where the differences between the experiment and the control simulation will be interpolated to the BIOME4 grid and added to a modern climatology. We adopt this procedure to facilitate data-model comparisons.

Methods

We will analyse the output from BIOME4

1. to determine whether the implication of simulated changes in climate for vegetation is robust across the suite of PMIP II models.
2. to provide a quantitative measure of the magnitude and importance of simulated changes in terms of changes in the area of major biomes. The BIOME4 output will be made available on the PMIP website, so that it can be used for regional analyses, including comparisons with pollen reconstructions, by other groups.

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NAO 6ka inter model comparison

People involved: Rupert Gladstone, Paul Valdes

Contact: Rupert Gladstone

Aim

To study the structure of the NAO in the model outputs from both the pre-industrial (pre-ind) model runs and the mid-Holocene (6ka) runs, both through calculation of a simple NAO index based on normalised differences, and through principal component analysis (PCA). Both approaches could utilise either sea level pressure (SLP) or surface temperature.

Methods

With the PCA approach we would be looking for the quadropole pattern that can be seen in the in the leading EOF for the observed 20^th century surface temperature field, with nodes centred over SE USA, NW Atlantic, NW Europe and the Middle East. To compare variability between models, we will look at the power spectra for the time series of the leading EOF. We intend to compare pre-ind to 6ka modelled NAO for each model. This will involve a straight comparison between the leading EOFs for both experiments, or, if appropriate, we could look for coupled modes of behaviour using singular value decomposition (SVD). We plan to investigate the effects of the 6ka NAO on European climate. For example, we could look for regions where the precipitation is closely correlated to the time series of the leading EOF. It may also be interesting to compare NAO between the runs with and without interactive vegetation.

Published papers

[ 08/01/05 ]

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Asian Summer Monsoon

People involved: Rupert Gladstone, Paul Valdes

Contact: Rupert Gladstone

Aim

We propose to study the changes in the Asian summer monsoon in the PMIP2 mid-Holocene simulations. Our analysis will focus on comparing the strength of the monsoon changes in the model, and understanding the causes of any model differences. We will examine both the OA simulations and the OAV simulations.

Methods

Our study will be in three parts:

1. Quantification of the mid-Holocene changes from the various models, and the extent of model-model variability.
2. Analysis of different dynamical and thermodynamical indexes of the monsoon to help relate the changes in the seasonal cycle with other aspect of the models (as in Braconnot et al., 2002, Climate Dynamics).
3. Comparison of simulated changes in precip (and related changes in biomes) to the BIOME6000 and lake level databases.

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Assessment of improvements in simulations due to incorporation of dynamic vegetation (specifically on role of snow albedo feedbacks) at LGM and mid-Holocene

People involved: Ian Ross, Sandy P. Harrison

Contact: Ian Ross

Aim

To determine to what extent the MOTIF atmosphere/ocean/vegetation coupled runs provide an improvement over atmosphere/ocean only simulations in the representation of vegetation feedbacks on climate during the LGM and mid-Holocene, concentrating particularly on snow/albedo feedbacks in boreal forest biomes.

Methods

1. For each model, direct comparisons will be made between climate output from the OA and OAV runs, diagnosing correlations between seasonal albedo changes due to the coupling of active vegetation into the models, and corresponding changes in temperature and precipitation regimes. This will provide qualitative and quantitative information about the influence of snow/albedo feedbacks on the climate of each model.
2. Inter-model comparisons will be performed in two stages:
   1. Comparisons will be made between the changes in albedo and in climate in each model that result from coupling of active vegetation. This will provide basic information about the relative sizes of changes produced by active vegetation in each model.
   2. An index of the regional snow/albedo feedback strength will be developed, based on correlations between albedo changes and climate changes, and comparisons of this index between different models will allow determination of the extent to which different models differ in their simulation of snow/albedo feedbacks.
3. Comparisons between model output and palaeodata records will be performed by examining correlations between biomes simulated by models (as derived from model vegetation output by a simple biome allocation model) and those reconstructed from pollen assemblages (as part of the BIOME 6000 project). These comparisons will be performed for both the OA and OAV runs for the LGM and mid-Holocene, and will provide information about changes in the fidelity of simulated vegetation between model runs with and without dynamic vegetation.
4. Combined analysis of the results from b.ii) and c) will provide additional information about the regional importance of snow/albedo feedbacks in the LGM and mid-Holocene, and the influence of the strength of such feedbacks on the fidelity of vegetation modelling.

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Evaluation of the realism of high-northern latitude surface climates at 6ka and 21ka through comparison

People involved: Jens Wohlfahrt, Sandy P. Harrison

Contact: Jens Wohlfahrt

Aim

To assess the realism of simulated northern hemisphere high-latitude climates through comparison of simulated and observed vegetation at the LGM and 6000 yr B.P.

Methods

We will:

1. compare observed changes in vegetation north of 40°N with simulated vegetation patterns from BIOME4 simulations driven by output from the 6ka OAGCM and OAVGCM simulations, using quantitative comparison methods developed by Wohlfahrt et al (2004).
2. compare observed changes in vegetation north of 40°N with simulated vegetation patterns from BIOME4 simulations driven by output from the LGM OAGCM and OAVGCM simulations.
3. for each set of simulations, we will identify robust patterns amongst the simulations, and responses that are model dependent. We will use MDS to establish the degree of similarity between the model simulations.
4. Examine the causes of the simulated changes in vegetation patterns, focusing particularly on changes in the tundra-taiga boundary and in the extent of mid-continental aridity in Eurasia.

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Comparison of simulations of the North American monsoon at 6ka and analysis of the role of vegetation feedbacks

People involved: Bob Thompson, Pat Bartlein, Sandy P. Harrison, Sarah Shafer

Contact: Bob Thompson

Aim

To determine whether the PMIP simulations produce a realistic simulation of the expansion of the North American monsoon and of the associated peripheral region of subsidence by comparing the simulated climate and vegetation changes with the multi-proxy data synthesis presented in Harrison et al. (2003).

Methods

We plan to:

1. analyse the surface climate fields (precipitation, P-E, soil moisture) from the 6ka OAGCM simulations to determine whether these simulations show the regional patterning of increased/decreased moisture availability shown by the observations
2. compare observed changes in vegetation in response to changes in moisture availability with simulated vegetation patterns from BIOME4 simulations driven by output from the 6ka OAGCM simulations (augmented with paleolimnological data and other indicators of past moisture availability)
3. examine the mechanisms driving the observed changes in surface climatology, to determine whether these are the same in all of the simulations
4. compare the simulated climates over North America in the OAGCM and OAVGCM simulations, in order to determine whether vegetation feedbacks have a significant impact on the extent of aridity induced by subsidence around the core of the monsoon
5. to compare the surface climate fields, and simulated vegetation patterns derived from these surface climatologies, with observations to determine whether the incorporation of vegetation feedback produces an improvement in the simulated 6ka climate of North America.

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Evaluation of bioclimatic parameters in data-model comparisons

People involved: Bob Thompson, Pat Bartlein, Sarah Shafer, Sandy P. Harrison

Contact: Bob Thompson

Aim

To evaluate uncertainty in the use of biomes and bioclimatic parameters for data-model comparisons, by:

1. characterizing the present-day bioclimatic parameters associated with Northern Hemisphere biomes,
2. comparing the biome-bioclimate characteristics between North America and Eurasia/North Africa, and,
3. comparing the bioclimatic conditions simulated by models with those implied by the data (and their associated bioclimatic characteristics).

Methods

We will utilize existing BIOME6000 biome assignments with modern climatic data from the Northern Hemisphere to evaluate the relative bioclimatic requirements (alpha, MTCO, MTWA, GDD5) of the biomes today. We will compare the relations between the bioclimatic parameters and the occurrence of biomes in North America with those of the same biomes in Eurasia and North Africa. We will also compare simulated bioclimates from PMIP2 model runs with the bioclimates implied by the BIOME6000 modern data.

Using the information from the analyses above, we will rank the biomes (allowing ties) for each bioclimatic variable. We will then compare the biomes of each past period (6ka, 21ka) with the present and use ranked list of biomes to qualitatively estimate the direction and intensity of the shift in each bioclimatic variable between the 6ka (and 21ka) and the present.

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Sensitivity of large-scale forcing of eastern boundary current regions to LGM and mid-Holocene boundary conditions

People involved: Noah Diffenbaugh

Contact: Noah Diffenbaugh

Aim

The subject of the analyses will be the seasonality and annual- to decadal-scale variability of large-scale forcing of eastern boundary current (EBC) regions. EBCs support highly productive marine ecosystems and exert strong control on adjacent terrestrial climate. They are forced by both regional- and large-scale processes, including annual to decadal modes such as ENSO and PDO. There is ample proxy evidence that EBC behavior was different than present during the LGM and mid-Holocene. The analyses will use output from the LGM, 6 ka, and pre-industrial GCM simulations. Model data will come from the time-independent 2-d land surface and ocean data, monthly-mean 1-d ocean data, monthly-mean 2-d atmosphere, land surface, ocean and sea ice data, and monthly-mean 3-d atmosphere and ocean data. The diagnostics will require some development, but it is expected that a combination of time-series analysis and mean anomalies will be used. The subproject will result in model-model inter-comparisons that could in turn be compared with existing proxy records from EBC regions. This PMIP2 analysis subproject will be performed in concert with an IPCC AR4 analysis subproject testing the ability of the participating coupled GCMs to reproduce observed records of 20^th century seasonality and variability of large-scale EBC forcing and evaluating those large-scale processes in the SRES A1B and B2 scenarios.

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Grassland C₃/C₄ balance during the LGM and mid-Holocene

People involved: Noah Diffenbaugh, Rhonda Friberg, David Fox, Paul Koch

Contact: Noah Diffenbaugh

Aim

This analysis subproject will use simulated C₃ and C₄ grass abundance to compare the PMIP2 GCM simulations with proxy data. In this forward modeling approach, the simple C₃/C₄ grass model of Koch et al., 2004, (adapted from Collatz) will be used to simulate C₃/C₄ grass abundance from the LGM and 6 ka GCM simulations. Inputs to the grassland model are mean monthly temperature, mean monthly precipitation, and ambient CO₂ level. The model could be refined by the use of daily minimum temperature data, if available. The PMIP2 BIOME4 simulations will be used to define grassland grid points in each GCM simulation. The climate fields (GCM anomalies added to observed baseline climate) will then be used in the Koch et al. grassland model to simulate C₄ percentages at each of the grassland grid points. A new global synthesis of C₄ grass percentage will also be generated from the literature. The C₄ percentages from the contributing GCMs will be both inter- compared and evaluated against the proxy data, resulting in both model-model and model-data comparisons.

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Cloud feedbacks

People involved: Michel Crucifix (Université Catholique de Louvain, Belgium), Thomas Schneider (PIK, Germany)

Contact: Michel Crucifix

Aim

The aim of this analysis is to intercompare the gain (feedback) produced by clouds in response to typical palaeoclimate forcings (LGM and 6K).

Methods

We have presently identified three analyses potentially useful considering both palaeoclimate and climate prediction prospectives.

1. We intend to to generalise to past climates previous works aiming at documenting the cloud feedback strength in models by reference to sea-surface temperature changes and vertical velocity (Williams et al., 2003; Bony et al. 2004). Where possible, it could be useful to use the ISCCP classification of clouds (will be available in the HadCM3 experiments of the LGM).
2. Using results of (a), we intend to determine whether the different cloud responses across models can explain differences in simulated tropical ocean temperatures. This is potentially relevant to IPCC AR4 because tropical ocean temperatures have been identified as a good candidate to assess climate models by reference to palaeodata.
3. We intend to determine whether the gain calculated for globally averaged quantities is constant, or at least similar, for different forms of forcing. For example, is the cloud forcing proportional to the globally averaged temperatures ? To answer this question, one need a significant number of different experiments, such as 21 K, 6 K, control, and future climates. The study is presently in progress using HadCM3 and HadSM3 experiments.

Published papers

[ 09/01/06 ]

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The Atlantic ocean response to LGM boundary conditions

People involved: Nanne Weber, Pedro de Vries (KNMI, NL) and Michael P. Erb (Rutgers University, New Brunswick, NJ, USA)

Contact: Nanne Weber

Aim

Which pysical processes effectively determine the response of the Atlantic meridional overturning circulation (MOC) to LGM boundary conditions is not yet fully understood. Different climate models have shown varying results: the MOC strength increases in some models and reduces in others, while the location and depth of deep-water formation also varies. We aim to diagnose the different responses by applying a stability analysis to the MOC.

Methods

The analysis consists of the following steps:

1. computation of the freshwater budget of the Atlantic basin for present-day and LGM boundary conditions. The terms in the budget are freshwater forcing at the air-sea interface, ocean transports through Bering Strait and through the southern boundary.
2. diagnose from the budget where different models are in the MOC hysteresis diagram for present-day and LGM conditions. This is expected to provide a framework for relating the varying responses to the separate responses in terms in the budget in different models.

Published papers

[ 02/01/07 ]

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Tropical  interannual variability in the mid Holocene

People involved: Ute Merkel, Mojib Latif, Christian Gerber

Contact: Ute Merkel

Aim

The aim of the study is to investigate the response of tropical mean climate and variability to 6K boundary forcing with a particular focus on the most prominent example of interannual variability, the El Niño/Southern Oscillation phenomenon.

Methods

1. First of all, the changes in the background state (annual mean SST, seasonal cycle of SST) in response to the 6K boundary forcing will be analysed for the tropical oceans. As has been shown in Latif et al. (2001), models may differ considerably in their simulations of the mean state and the seasonal cycle. Therefore, it will be investigated to which extent these properties are changed under different boundary conditions.
2. In a second step, we will diagnose the SST indices for the Niño3 and Niño4 regions. Furthermore, the standard deviations of the Niño3 SST anomalies will be computed as a function of calendar month to investigate the ENSO phase locking to the annual cycle and to investigate changes in variability.
3. ENSO largely arises from air-sea interaction. In order to take that into account we will also try to establish relationships between SST, the subsurface ocean structure (ocean heat content) and wind stress using statistical methods. In the light of anthropogenic climate change, the results are expected to contribute to the discussion on how sensitive ENSO responds to changes in boundary forcing.

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Fuzzy  logic-based model-data comparison

People involved: Joël Guiot, Simon Brewer

Contact: Joël Guiot

Aim

We plan to compare the output of the PMIP II models for the mid-Holocene with the results of continental palaeoclimate reconstructions in Europe and Africa. The comparisons are based on the suite of climate parameters best reconstructed from fossil pollen data (GDD5, MTCO, E-PET), and use the methodology proposed by Bonfils and Guiot in the first PMIP project, with some changes. It was suggested at the last meeting that this methodology could be equally be applied to marine data, when available.

Methods

1. if the model reconstructs the same directions of climate change observed in the data;
2. if the model reconstructs these changes in the same geographical location as the data.

We use k-means cluster analysis on the proxy-based climate data in order identify regions of similar climatic change at 6ka BP, e.g. colder winter temperatures, higher E-PE. Model grid points are assigned to each of these clusters using a measure of fuzzy distance, which allows us to take into account the model variance as well as the size the data clusters. Two measures of the fit between model and data are obtained: the average fuzzy distance over all grid points and the average geographical distance to the 'correct' observed data cluster.

Published papers

[ 03/02/07 ] [ 05/29/07 ] [ 08/21/07 ]

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Lagrangian analysis of the Ocean circulation

People involved: Sabrina Speich, Bruno Blanke

Contact: Sabrina Speich

Aim

To investigate changes in the thermohaline circulation and implications for the features of the global ocean conveyor belt (GCB) in LGM and present climate simulations.

Methods

The GCB will be qualified and quantified by means of recently developed Lagrangian diagnostics (ARIANE) applied to the output of PMIPII ocean models. Total transport of the upper and lower branches of the GCB will be quantified, including a careful inventory of the exact origins for the components of the upper limb: Drake Passage, Indonesian Throughflow, or South of Tasmania. The diagnostics will be extended to evaluate the way ocean ventilation is active throughout the global ocean, and differs from present climate conditions. We will evaluate the connections established on a global scale, with an appropriate mapping of the ventilation and corresponding subduction regions with the calculation of associated time scales. We will check whether the present role of the Antarctic Circumpolar Current as the main receptacle of the water masses formed throughout the world ocean still holds for past climate conditions.

More details can be found in the Lagrangian Analysis page.

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African 6ka monsoon

People involved: Pascale Braconnot

Contact: Pascale Braconnot

Aim

Methods

Published papers

[ 04/01/07 ]

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LGM tropics

People involved: Ralph Schneider, Bette Otto-Bliesner

Contact: Ralph Schneider

Aim

To assess the realism of simulated tropical sea surface temperatures at LGM by the PMIP-2 models, identify basin differences in cooling, and identify seasonal and depth considerations in the interpretation of proxies of LGM tropical SSTs.

Methods

We plan to:

1. analyze the sea surface temperatures and surface heat budget predicted by the PMIP-2 models for the LGM for 30° N-30° S
2. compare differences in cooling between the Atlantic, Indian, and Pacific Oceans and zonal asymmetries within each ocean basin.
3. compare simulated ocean temperatures along a tropical average longitudinal transect at the surface and depths to 400m with proxy estimates from the MARGO project.
4. compare PMIP-2 simulated tropical SSTs at LGM with slab ocean simulations available for LGM.

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LGM model-data comparison over North Atlantic

People involved: Masa Kageyama, Chris Hewitt, Alexandre Laine

Contact: Masa Kageyama

Aim

Comparison of the sea surface temperatures simulated by the PMIP coupled models to the available reconstructions for the North Atlantic

Methods

Simple model-data comparison:

1. site to site comparison (scatter plots)
2. comparison of sectorial averages (e.g. longitudinal average for the North Atlantic)
3. according to the type of reconstruction (to be discussed with the specialists for each data type), we will also investigate several depths in the near surface ocean
4. interannual and decadal variability and their potential influence on the results of the comparison will be investigated: we will examine whether there are some periods for which model and data agree better than others.

Possible extension of this work to the GIN seas.

Published papers

[ 09/01/06 ] [ 11/01/06 ] [ 06/18/07 ]

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LGM fresh water budget

People involved: Masa Kageyama, Ramdane Alkama

Contact: Masa Kageyama

Aim

Investigating the influence of taking LGM river routes into account in the coupled LGM simulations

Methods

1. comparison of a simulation with present river routes to a simulation with LGM river routes
2. comparison of all steps in the hydrological cycle (precipitation, evaporation, tracking of the fresh water to the ocean)
3. investigation of the impact of these changes in river routes on the atmospheric (occuring through changes in soil moisture and evaporation, as observed in equivalent atmosphere-only runs) and oceanic circulations.

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LGM tropical lapse rates

People involved: Masa Kageyama, Sandy P. Harrison

Contact: Masa Kageyama

Aim

Investigating changes (LGM vs. present and interannual variability) in tropical lapse rates and 0°C-isotherm heights

Methods

Taken from our previous work on tropical lapse rates in PMIP1 simulations, to be published soon (article available on request)

1. Computation of 0°C isotherm heights for the warmest month as a proxy for snow lines. For the PMIPII simulations, we will perform this computation on a longitude-latitude basis (instead of zonal averages which were available from PMIP1).
   
   
2. Computation of the free atmospheric lapse rates for the warmest month as well as for the annual averages, on a longitude-latitude basis.
   
   
3. The interannual variability of these quantities will be investigated, in relation with tropical SST interannual variability.

Published papers

[ 06/20/05 ]

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Climate sensitivity

People involved: Karl Taylor, Pascale Braconnot, Chris Hewitt, Bette Otto-Bliesner

Contact: Karl Taylor

Aim

Methods

Published papers

[ 10/11/06 ]

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Comparison of surface ocean fluxes and water-mass transformation rates in PMIP-2 simulations for LGM

People involved: Esther Brady, Bette Otto-Bliesner, Sang-Ik Shin

Contact: Bette Otto-Bliesner

Aim

To compare changes in the surface momentum, heat, and freshwater fluxes and water mass transformation rates simulated by the PMIP-2 models for LGM.

Methods

We plan to:

1. analyze geographic patterns of surface momentum, heat, and freshwater fluxes in the AOGCM simulations for LGM and PI.
2. compute the haline and thermal components of the water mass transformation rates for the Indian-Pacific, Arctic-Atlantic and Southern Oceans following Speer and Tziperman, 1992.

Published papers

[ 06/01/07 ]

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Model-data comparisons of North American biomes at LGM

People involved: Bette Otto-Bliesner/Bob Thompson, ...

Contact: Bette Otto-Bliesner

Aim

To determine if the PMIP-2 AO and AOV simulations produce a realistic simulation of the biome changes at LGM.

Methods

We plan to:

1. analyze the surface climate fields (precipitation, P-E, soil moisture) from the 21ka AOGCM simulations to determine whether these simulations show the regional patterning of increased/decreased moisture availability shown by the observations
2. compare observed changes in vegetation in response to changes in moisture availability with simulated vegetation patterns from BIOME4 simulations driven by output from the 21ka AOGCM simulations
3. examine the mechanisms driving the observed changes in surface climatology, to determine whether these are the same in all of the simulations
4. compare the simulated climates over North America in the AOGCM and AOVGCM simulations, in order to determine whether vegetation feedbacks have a significant impact on the prediction of biomes at 21ka
5. to compare the surface climate fields, and simulated vegetation patterns derived from these surface climatologies, with observations to determine whether the incorporation of vegetation feedback produces an improvement in the simulated 21ka climate of North America.

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Estimating climate sensitivity from model-data comparisons at LGM

People involved: NCAR/USGS group

Contact: Bette Otto-Bliesner

Aim

To assess with PMIP-2 model-data comparisons can provide a constraint on the range of climate sensitivity predicted by IPCC AR4 coupled models for future scenarios of increasing greenhouse gases.

Methods

We plan to:

1. compute global and regional average cooling predicted by the PMIP-2 LGM simulations and, when available for the same models compute these temperature changes for future scenario simulations.
2. calculate forcing contributions.
3. analyze the role of low and high clouds in producing these temperature changes.
4. compare to proxy estimates of LGM cooling to assess whether PMIP-2 can constrain the range of climate sensitivity.

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Mid-Holocene Climate Variability in Europe and Africa

People involved: Simon Brewer, Yannick Garcin, Joël Guiot

Contact: Simon Brewer

Aim

Changes in climatic variability will be investigated on a European-African transect, by comapring high resolution proxy-data records with GCM output.

Methods

The variability change is based on the difference in the record's variance during the period around 6 ka BP and the last 1000 years. Mapping these changes wil allow a spatial picture of variability change to be established. Changes in variability will also be examined in a set of lower resolution climate reconstructions from Europe, to establish if similar patterns emerge. The results will be compared with a similar indices of change from the GCM output.

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Comparison of simulated vegetation in eastern Africa at 6ka BP using the LPG-GUESS model

People involved: Christelle Hély-Alleaume, Joël Guiot, Simon Brewer

Contact: Christelle Hély-Alleaume

Aim

GCM climate simulations will be tested for the modern period and the mid-Holocene, by using their output to simulate eastern African vegetation, via the LPG-GUESS vegetation model.

Methods

The LPG-GUESS dynamic vegetation model will be run off-line using the output of both coupled and non-coupled GCMs for the modern period and the mid-Holocene.
A series of test will be made to examine the effect of climate variability on the simulated vegetation:

1. using 0ka model mean values alone
2. using 0ka model mean values adjusted to take into account the modern climate variability (CRU dataset)
3. using 6ka model mean values with modern variability
4. using 6ka model mean values adjusted to an approximation of 6ka climate variability.

The resulting simulated mid-Holocene vegetation will be compared to the vegetation recosntructed from fossil pollen sites.

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Polar amplification of climate change

People involved: Valérie Masson-Delmotte, Masa Kageyama

Contact: Valérie Masson-Delmotte

Aim

We plan to compare the model outputs for Greenland and Antarctica with the climate reconstructions from polar ice cores.

Methods

Key questions are:

1. how representative are polar regions of global temperature changes?
   This requires to compare, for each model, the polar temperature change to the global and hemispheric mean temperature changes. We will provide up to date estimates of past temperature changes from several ice cores at both poles with uncertainties.
2. can polar records provide constraints on the level of polar amplification?
   In the line of Holland et al, 2003 we would like to compare the level of polar amplification in future climate simulations with the level of polar amplification in past climate simulations. This analysis may also be relevant for climate sensitivity too.
3. how biased are stable isotope records of past climate?
   Water stable isotope measurements in ice cores sample climate changes only when there is snowfall. Earlier modelling studies had shown that Greenland precipitation seasonal cycle changes significantly under glacial conditions. We plan to compare the seasonal cycle of temperature and precipitation simulated by the models and evaluate the annual mean precipitation-weighted temperature changes in order to estimate this source of bias.
4. how realistic are polar climate changes simulated by climate models?
   We will use the state of the art temperature and accumulation reconstructions at the poles to assess the capacity of climate models to simulate the mean climate changes at these locations. For the mid Holocene Greenland data offer a 4 year temporal resolution and Antarctica data a 20 year resolution which could also enable to look at parts of the climate variability. For the LGM the temporal resolution is also lower but still as high as a few decades at both poles.

Published papers

[ 04/01/06 ] [ 10/26/06 ]

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Can ice sheet models be used for diagnostic of PMIP experiments ? A sensitivity study with different ISM

People involved: Sylvie Charbit, Catherine Ritz, Ayako Abe-Ouchi, Fuyuki Saito, Lev Tarasov, Dick Peltier, Dave Pollard, Tony Payne, Ian Rutt, Ralf Greve, Shawn Marshall, Philippe Huybrechts and Chris Zweck

Contacts: Sylvie Charbit and Catherine Ritz

Aim

We plan to use the PMIP climatic outputs to force a set of different ice sheet models to study the sensitivity of ice sheets to both internal and dynamical processes and to climate-related mechanisms.

Methods

We propose to:

1. Test the ability of PMIP models to produce a glacial inception.
   Key analyses are:
   1. Starting with a present-day ice sheet configuration, we plan to force the different ice sheet models with a glacial climate and to examine whether inception is possible, and if so, where are located the sites of ice nucleation ?
   2. To perform ice sheet simulations under constant 115 kyr climate forcing
   3. To use the climatic index method associated with two (at least) climate snapshots to force the ice sheet models over a full glacial-interglacial cycle.
2. Test the climate models at the last glacial maximum. It is to examine whether ice sheets are maintained at the LGM when they are forced by the 21 kyr climate simulated with ICE-5G ice sheets as boundary conditions. The second point is to study the differences with the transient responses of the ice sheets over a glacial-interglacial cycle, or just over the last deglaciation period, using in both cases the climatic index method.
3. To perform an intercomparison of ice sheet models using as climate forcing either several PMIP models or a kind of mean PMIP output.

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Monsoon around Asia and North Pacific at LGM and mid-Holocene

People involved: Ayako Abe-Ouchi, Akio Kitoh, Rumi Ohgaito, and Wataru Yanase

Contact: Wataru Yanase

Aim

We plan to investigate the response of summer and winter monsoon around Asia and North Pacific at LGM and mid-Holocene by PMIP 2 models. We will describe robust changes in the simulations and variability between models, and will discuss their dynamics.

Methods

1. For winter monsoon, we will compare the change of surface meridional wind over East Asia, the strength and meridional location of the upper-level westerly jet.
2. For summer monsoon, we will compare the change of precipitation and surface wind around Asia and North Pacific. In particular, we focus on changes in seasonality for Asian monsoons, such as onset, peak, duration and withdrawal of rainy season.
3. For the next step of a and b, we will examine the change of heat and moisture balance in the atmosphere and at the surface.
4. We compare the robust climate change in the simulations with the proxy data such as vegetation, lake level and dust transport.

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THC  regime and salinity response (to LGM climate)

People involved: Shigenori Murakami, Kotaro Sakai, Rumi Ohgaito, Ayako Abe-Ouchi

Contact: Shigenori Murakami

Aim

THC responses to climate change are basically controlled by the surface flux changes. However, THC responses to fresh water flux changes are not clearly understood. Theoretically, effects of fresh water forcing changes depend on the THC regime, and the THC mode of the real Atlantic ocean is still unknown. This subproject addresses to this problem by analyzing the relationship between surface flux changes and salinity responses in LGM (and control) simulations. The analysis is also thought to be useful to understand the different responses of the THC to climate change simulations with several CGCMs.

Methods

1. calculate heat and fresh water budget over each ocean basin in LGM and CTL simulations.
2. calculate meridional profiles of depth averaged theta, salinity and density for each ocean basin in LGM and CTL simulations.
3. analyze the relation between salinity response and fresh water budget changes.
4. analyze the relation between theta, salinity and density responses.

Published papers

[ 02/13/08 ]

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Influences of sea ice on air and water masses at LGM and mid-Holocene

People involved: Tatsuo Motoi

Contact: Tatsuo Motoi

Aim

To study the influences of sea ice on air and water masses in the differnt climate, model results from LGM and mid-Holocene PMIP2 experiments will be compared. Posible proxy data will be used to evaluate the model results. Feedback processes which amplify or reduce the forcing will be investigated by model data analyses. Impact of changes in air and water masses on those in the atmosphere and ocean general circulations will be investigated.

Methods

1. The position of the sea-ice edges, sea-ice thickess, compactness and albedo will be compared. The impact of the differnces in these sea-ice conditions on air and water masses will be examined.
2. Heat and water exchanges between the atmosphere and ocean or sea ice will be examined by using the components of heat and water fluxes.
3. The positive and negative feedbacks involving heat and water exchanges will be analyzed.
4. The meridional circulation changes in the atmosphere and ocean will be estimated to detect the effect of changes in air and water mass on those in the atmosphere and ocean general circulations.

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The Southern hemisphere westerlies during the LGM and mid-Holocene

People involved: Maisa Rojas, Patricio Moreno, Michel Crucifix and Chris Hewitt

Contact: Maisa Rojas

Aim

The aim of our study is to investigate the causes (insolation-driven, landscape/biotic/greenhouse gases) of observed climate changes related to the position and intensity of the Storm tracks in the in the Southern Hemisphere mid latitudes.

Methods

We propose to conduct analyses of PMIP2 experiments for the LGM and 6ka with respect to their simulations of the Southern hemisphere westerly winds, with special emphasis on the South Pacific/South American continent. In particular we will use HadCM3, as this model will be used to drive a regional climate model to simulate the two mentioned periods over a domain encompassing western Patagonia (39-54S).

Published papers

[ 06/03/08 ]

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Ecological niche modeling: a novel tool in phylogeographical studies

People involved: Tereza Jezkova, Mark Sappington and Brett Riddle (University of Nevada, Las Vegas)

Contact: Tereza Jezkova

Aim

This project pioneers a new methodology connecting phylogenetics with Geographical Information Systems (GIS) and computer-based ecological modeling. The goal is to demonstrate that this multi-disciplinary approach represents an efficient tool for building and testing complex models of biotic structuring through time and space.

Methods

We will apply molecular methods versus modeling capabilities to several taxa co-distributed within the Great Basin (Nevada, USA) to characterize phylogeographic structuring of species assemblages and evaluate their responses to past climatic changes.

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Climate history and biological diversity

People involved: David Nogués-Bravo, Miguel B. Araújo and Mark New (Evora University, Portugal)

Contact: David Nogués-Bravo

Aim

There is a well known latitudinal gradient in species diversity, from low diversity at high latitudes and high diversity at low latitudes. We are interested in exploring whether the spatio-temporal distribution of past climate conditions is an important explanatory variable. Specifically we wish to quantify the relationship between stability of climatic-envelopes and species diversity. In summary, we are searching a based quantitative explanation of conservationism niche theory.

Methods

We need estimates of the spatial and temporal variability of climatic envelopes, from the Tertiary to the present. For example, for low latitudes, we may want to know the space-time distribution of the area of the earth that has temperatures greater than 25C, and precipitation greater than 1200mm.

We would like to use palaeoclimate simulations with global climate models to estimate these spatio-temporal climate patterns. The general approach is to assemble spatial patterns of mean climate from GCM simulations for as many periods in the past and then to calculate a transfer function between these patterns and global temperature. The spatio-temporal patterns through time can then be estimated, to first order, by applying the transfer function to the global temperature record estimated from ocean cores.

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Distribution of mammals during the last glaciation

People involved: Robert Hijmans (Museum of Vertebrate Zoology, University of California)

Contact: Robert J. Hijmans

Aim

To better understand the current patterns of biodiversity.

Methods

Using the PMIP data and species distribution models I will generate historic distributions, and analyze these in relation to the current patterns.

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Simulated Australian Climates at the LGM and mid-Holocene

People involved: Pandora Hope (Bureau of Meteorology Research Centre, Australia), Josephine Brown (Monash University, Australia)

Contact: Pandora Hope

Aim

To assess the range of climates simulated by PMIP2 and PMIP models in the Australian region, and compare with proxy evidence. Some of the potential drivers of this range will be investigated.

Methods

The range of basic climate variables such as near-surface temperature and precipitation totals in the model output will be determined for the Australian region. These values will be compared against proxy evidence from across Australia. The oceanic forces contributing to the range of modelled climate responses will also be considered.

This project will tie in with both LGM tropics and Southern hemisphere westerlies during the LGM and mid-Holocene.

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Data-model comparison of the vegetation at 6k in western Europe

People involved: Jeanne-Marine Laurent, Rachid Cheddadi, Louis François

Contact: Jeanne-Marine Laurent

Aim

We plan to make simulations with the CARAIB dynamic vegetation model (vegetation distribution + carbon cycle) using outputs from the 6 ka ocean-atmosphere and ocean-atmosphere-vegetation models. We intend to examine the simulated distribution of plant types and compare them to palynological observations. This work will be included in a study of vegetation dynamics at the scale of France, since the Last Glacial Maximum. A series of analyses will be made to examine the influence of climate evolution on plant migration patterns and chronology.

Methods

The CARAIB vegetation model will be run offline using the outputs of both GCMs for the mid-Holocene, using climatic anomalies. We will:

1. Compare observed distribution of vegetation to CARAIB outputs, using quantitative comparison methods developed by Laurent et al (submitted to Global and Planetary Change).
2. Analyze the causes of discrepancies between data and model and examine the role of possible model failures (climate and vegetation) in these discrepancies.

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South American Monsoon

People involved: Bruno Turcq, Pedro Da Silva Dias, Illaina Wainer, Pascale Braconnot, Myriam Khodri

Contact: Bruno Turcq

Aim

The American Monsoon includes different atmospheric mechanisms partly controlled by oceanic conditions (South Atlantic Convergence Zone, Intertropical Convergence Zone, Low Level Jet, cold frontal systems) and ocean alone processes (inter-hemispheric SST gradient, equatorial dynamics, tropical-extratropical exchanges of water masses). We propose to study the changes in these processes in the PMIP2 mid-Holocene simulations and compare them with existing paleodata. Our analysis will focus on the intensity of the phenomena and the variability of their geographical position. We will examine both the OA simulations and the OAV simulations.

Methods

1. Reconstruction of past climate and vegetation in tropical South America based on existing data.
2. Reconstruction the Sea Surface Temperature (SST) in the Tropical and South Atlantic Ocean based on existing data.
3. Analysis of control simulations for tropical South America and Tropical/South Atlantic.
4. Quantification of the mid-Holocene changes from the various models, for the mean climate and climate variability.
5. Explore the impact of vegetation and oceanic feedbacks on South America monsoon changes.
6. Analysis of the causes of model-model biases and variability and model-data dissimilarities.
7. Impact of changes in the coastline based on downscaling modeling of past climate scenarios.

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Modelling a Fennoscandian Ice Sheet with a mass balance parameterisation including the effect of orography and advection

People involved: Jojanneke van den Berg, Hans Oerlemans and Roderik van de Wal (Institute for Marine and Atmospheric Research, University of Utrecht, The Netherlands)

Contact: Jojanneke van den Berg

Aim

We wish to create a surface mass balance model to force an ice dynamical model of the Fennoscandian Ice Sheet (FIS) through a full glacial cycle. Instead of perturbing current precipitation patterns (a method commonly used in glaciology), we want to calculate the precipitation from a temperature field with a parameterisation that includes explicitly advection and orographic effects. This has the advantage that we can incorporate the dominant physical processes, while keeping the mass balance model as simple and time-efficient as possible.

We wish to use the outputs of several GCM's at present day and at the Last Glacial Maximum (LGM) to tune and to test the parameterisation of the surface mass balance model.

Methods

1. Use current temperature, wind and precipitation fields to tune the mass balance model to present day conditions.
2. Use LGM temperature, wind and precipitation fields to calculate the mass balance at LGM.
3. Use differences between several GCM outputs to assess the effects of uncertainties on the mass balance model and resulting ice sheet.
4. Use the temperature from several GCM outputs to assess the forcing function (e.g. temperature perturbations from GRIP) for its validity over Northern-Europe and Siberia.

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The impact of OIS 3-2 rapid climatic variability on the human and large mammal communities of Western Europe

People involved: Francesco d'Errico, William E. Banks (Institut de Préhistoire et de Géologie du Quaternaire, Bordeaux, France), A. Town Peterson (University of Kansas, Lawrence), Robert J. Hijmans (University of California, Berkeley)

Contact: Francesco d'Errico and William E. Banks

Aim

We will attempt to model the impact of the OIS2-3 millennial-scale climatic variability (Dansgaard-Oeschger oscillations and Heinrich events) on the human populations of Europe.

Methods

We will employ an approach termed Eco-Cultural Niche Modeling (ECNM), utilizing Genetic Algorithm for Rule-Set Production (GARP) software. GARP is a machine-learning genetic algorithm that uses geographic and climate data to create an ecological niche model for a species, which represents the environmental conditions in which that species could maintain a population. A niche model for a species in the past can be produced by integrating paleoclimatic data and the geographic coordinates of localities where the species was observed prehistorically (e.g. archaeological sites) or by projecting an ecological niche model for one time period onto modeled climates for a second time period and testing the ability of this model to predict known occurrences for the second time period. In the case of archaeologically defined populations, ECNM predicts a baseline distribution that represents the territory in which a specific population could have been present. We will produce Eco-Cultural Niche Models based on the geographic coordinates of archeological sites dating to specific time periods (e.g., the Last Glacial Maximum, Heinrich Event 4) and climatic interpolations for each of these time periods. In parallel and based on faunal remains recovered from archaeological sites, ecological niche models for large ungulate species exploited by prehistoric hunter-gatherer populations will be created in the same manner. This analytical approach will allow us to evaluate the rules and driving forces behind human-environmental interactions and help us to assess and understand the influence of environmental constraints on human social and technical systems, cognition, and communication. Identification of the geography of past culturally coherent human groups and their temporal geographic variability is critical to understanding the complex mechanisms that have shaped the interactions between genetics, linguistics, cultural affiliation, and climate. This research is being conducted as part of an interdisciplinary project funded by the European Science Foundation EuroCLIMATE program RESOLuTION.

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Modeling plant species distributions

People involved: Peter B. Pearman, Christophe Randin, Thomas Czaka, Antoine Guisan (University of Lausanne), Willem O. van der Knapp (University of Bern)

Contact: Peter B. Pearman

Aim

We intend to evaluate the temporal transferability of plant species distribution models.

Methods

Using knowledge of the current physiological limits of particular plant species, we will create models of species distributions at 6000ybp and LGM. We will compare the results of these models to data on previous species distributions.

Published papers

[ 02/12/08 ]

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Wind influence on the glacial ocean circulation

People involved: André Paul, Jörg Franke, Xavier Giraud (University of Bremen, Germany)

Contact: André Paul

Aim

We want to determine the influence of the sea-surface wind stress distribution on the circulation and water mass distribution of the glacial ocean.

Methods

We will take the windfields from the PMIP2 glacial climate simulations to force the University of Victoria Earth-System Climate Model as well as a regional ocean model. We will then carry out model-data comparisons (with the glacial radiocarbon and other paleo-proxy data, e.g. from the GLAMAP 2000 and MARGO projects) and model-model comparisons (with the fully coupled atmosphere-ocean models participating in PMIP2).

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Global budgets of well-mixed greenhouse gases at the LGM

People involved: Jed O. Kaplan (University of Bern, Switzerland)

Contact: Jed O. Kaplan

Aim

The Paleo Trace Gas and Aerosol Challenge (I.C. Prentice, ca. 1999) remains one of the major scientific endeavors in understanding the Earth System. The concentrations of trace gases recorded in polar ice are diagnostic of changes not only in the climate system but also in the biosphere and even the lithosphere. This analysis aims to incrementally further our understanding of trace gas sources and sinks in the Quaternary using the PMIP2 archive as a starting point. Linked to terrestrial vegetation models and atmospheric chemistry-transport models, paleoclimate scenarios provide the basis for understanding the mechanisms in the atmosphere, on land and in the oceans that control the observed record of variability in atmospheric trace gases.

Methods

Using PMIP2 model output, I will drive latest-generation global vegetation models (BIOME4-TG, LPJ-TG) to simulate surface emissions of CO₂, reactive trace gases (and possibly aerosol). These fields will ultimately be linked to atmospheric chemistry-transport models to diagnose trace gas concentrations which may, e.g., be compared to trace gas concentrations retrieved from polar ice cores.

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Extra tropical impacts of tropical climate change during the Last Glacial Maximum

People involved: Myriam Khodri, Bruno Turcq (IRD, France), Pascale Braconnot and Françoise Vimeux (LSCE, France)

Contact: Myriam Khodri

Aim

Our plan is to use PMIP-2 model simulations to study the global impact of the reorganizations of tropical climate that occurred at the LGM in both a regional and global way.

Methods

Analogous to the strong ENSO focus of tropical paleoclimate studies, we best understand how the tropics impact extratropical climate in terms of ENSO forcing of teleconnection patterns, or Rossby wave trains, that arc from the tropical Pacific into mid-latitudes. The coupled GCM experiments will provide a suite of altered tropical and global climate states for LGM that will be imposed to a simple dry baroclinic steady state stationary wave model. By applying either the altered LGM atmospheric structure or the altered tropical atmospheric diabatic heating, we will examine how in each model these changes impact the extratropics using both Rossby wave train and symmetric variability lines of reasoning. A few major issues will be focused on:

1. How is the extratropical circulation altered by the changes in distribution of tropical convection? Are the known present day ENSO teleconnection patterns still at work at the LGM and are they consistent among the PMIP2 OA model simulations for LGM?
2. How are jet stream locations in both hemispheres influenced by the altered tropical diabatic heating and by the local extratropical forcing due to LGM boundary conditions? Can a different heating distribution transform the two jet structures of the North Atlantic sector into a single jet structure akin to the Pacific, with dramatic consequences for North Atlantic climates?
3. By choosing key paleoclimate observations in both tropical and extratropical latitudes and studying the processes that can explain the teleconnection patterns that emerge from the data, we seek to produce, using PMIP2 models, physically-based processes for climate change at the LGM respectively to the present day.

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Simulations of Biogeochemical Tracers Under Last Glacial Maximum Conditions

People involved: Samar Khatiwala (Lamont-Doherty Earth Observatory, USA)

Contact: Samar Khatiwala

Aim

The broad aim of the proposed research is to understand the various physical and biogeochemical factors controlling the distribution of paleoceanographic proxy tracers such as isotopes of Nd and delta-C₁₃. Specifically, we are interested in carrying out a comparison of various steady state tracers such as radiocarbon, delta-C₁₃, and Nd isotopes between LGM conditions and present-day climate.

Methods

To facilitate our goal, we have recently developed a novel computational framework for biogeochemical tracer simulation known as the transport matrix method. The underlying idea is that the discrete tracer transport operator of a GCM can be written as a matrix, which may be constructed by probing the GCM (with idealized basis functions). The matrix method has two key advantages over GCMs or off-line tracer models. First, it is many orders of magnitude more efficient. Second, it can directly compute steady state solutions of the tracer equations, thus circumventing expensive, transient integrations. This is especially useful for tracers such as C₁₄, carbon, and nutrients.

To apply the transport matrix method requires the availability of an OGCM that has been spun up to equilibrium. We propose to use LGM and modern day (control) air-sea fluxes from the PMIP-2 coupled models to drive an ocean GCM to equilibrium. That is, we propose to diagnose the fluxes between the ocean and atmosphere from the output of coupled models participating in PMIP-2, and use these boundary conditions to force a similarly configured ocean GCM. (We will use the MIT ocean model, since the transport matrix method has been implemented in that code.) While this strategy is by no means guaranteed to work (in the sense of being able to reproduce the circulation in the coupled model), there is some previous work (e.g., Delworth and Greatbach, 2000) that is quite encouraging. Once the model has been spun up (for LGM and modern forcings), we will derive the transport matrix for the underlying circulation. This (seasonally-varying) matrix will then be used to perform various biogeochemical tracer simulations. These simulations will be used to evaluate model skill with regard to ventilation rates and pathways as inferred from paleoproxies, as well as to examine the sensitivity of paleoceanographic tracer distributions to boundary conditions.

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Tropical marine climate feedback to mid-and-high latitude climate change

People involved: John Chiang and Yue Fang (University of California, Berkeley, USA), Ping Chang (Texas A&M University, USA)

Contact: John Chiang

Aim

Our goal is to explore the influence that extratropical climate changes have on the tropical Pacific and Atlantic mean climate and variability, based on a hypothesis developed previously for extratropical influence on the tropical climate through the so-called Meridional Mode pattern of atmosphere-ocean variability (Chiang and Vimont 2004; Chiang et al. 2003). We are specifically interested in the way that coupled tropical ("ENSO-like") ocean-atmosphere processes respond to extratropical influences.

Methods

We are targeting two past climate scenarios - mid-Holocene and LGM - to explore the hypothesis. We are using a simpler coupled model (Community Climate Model version 3 coupled to a reduced-gravity tropical ocean model) to explore the range of potential tropical behavior associated with mid-Holocene and LGM changes in the boundary conditions, including changes to the tropical marine mean state, annual cycle, and variability We propose to use the PMIP Holocene and LGM simulations to assess the broader applicability of our ideas. Our project is funded by NSF (2005-2007).

References

• Chiang, J. C. H., and D. J. Vimont: Analogous Pacific and Atlantic meridional modes of tropical atmosphere-ocean variability. Journal of Climate, 17, 4143-4158 (2004)
• Chiang, J. C. H., M. Biasutti, and D. S. Battisti: Sensitivity of the Atlantic ITCZ to Last Glacial Maximum boundary conditions. Paleoceanography, 18, 10.1029/2003PA000916 (2003)

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Link between accumulation and temperature changes over ice sheets

People involved: Gerhard Krinner, Catherine Ritz and Frédéric Parrenin (LGGE, Grenoble, France)

Contact: Gerhard Krinner

Aim

Glaciological dating of ice cores is based on a fairly strong hypothesis, namely that past accumulation rates are tightly linked to past temperatures which can, in a more or less reliable way, be deduced from the isotopic composition of the ice. This hypothetic link is based on the fact that the saturation water pressure of the air is a strong function of temperature. Although such a link seems to exist on continental scales (e.g. predicted future precipitation increase over Antarctica and Greenland), it might be an oversimplification to pretend that such a link remains valid on smaller scales, and that it would remain constant in time. We propose to analyse the PMIP 2 simulations in order to test the reality of this link between accumulation and temperature, and to quantify it if possible.

Methods

Changes of simulated accumulation (P-E) and air temperature over the ice sheet interior regions (e.g. between present and the LGM, present and 6k) are calculated and compared. A regression of accumulation changes against temperature changes allows to assess the tightness of the link between these two variables and to quantify it. This is done for all models and time periods. Special attention is paid to spatial variability of the temperature-precipitation covariance. An assessment of the model skill for the present-day simulation (quality of the representation of present-day temperature and accumulation on the ice core drilling sites) allows to refine the results.

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Exploring the effects of LGM SST patterns upon stable water isotopes in an AGCM

People involved: Maxwell Kelley, Jean Jouzel and Valérie Masson-Delmotte (LSCE, Gif-sur-Yvette, France)

Contact: Maxwell Kelley

Aim

To investigate the effect of sea surface temperature patterns at the LGM upon stable water isotopes in precipitation. The scenarios in the different PMIP2 experiments constitute a set of possibilities constrained by model physics.

Methods

Ocean temperatures and sea ice concentrations from selected 0 kyr and 21 kyr experiments will be applied as a lower boundary condition for the atmospheric component of a version of GISS model II equipped with stable water isotope physics. Changes of simulated isotopic ratios between 0 and 21 kyr will be compared with those of ice-core records.

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Water, Life and Civilisation

People involved: Steven Mithen (lead PI), Brian Hoskins, Julia Slingo, David Grimes, Bruce Sellwood, Emily Black and Charlie Williams (University of Reading, UK)

Contact: Emily Black (WLC project manager)

Aim

To assess how the changes in hydrological climate have impacted human activities in the past, present and future within the semi-arid regions of the Middle East and North Africa (MENA).

Methods

The project will have five component parts consisting of two models, one for climate and one for hydrology, and studies concerning palaeoenvironments, the history of human settlement, and the current and future patterns of land use. In essence, the combined climate and hydrological models will provide predictions for the water cycle and river system for several key study dates. The predictions will be evaluated using palaeoenvironmental and archaeological data. The consequences for human activity will be assessed by the developmental geography studies drawing on the present character and forces of economic and social change.

    More information: www.waterlifecivilisation.org

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Estimating the location of biological refuges in the Iberian Peninsula

People involved: Jorge M. Lobo (Museo Nacional de Ciencias Naturales, Madrid, Spain)

Contact: Jorge M. Lobo

Aim

The Iberian Peninsula has been established as one of the main refuge centres during interglacial cycles. We are interested in proposing the location of these refuge regions in the Iberian Peninsula taking into account past climatic conditions and unavoidable pathways routes established with unchanged topographical variables. The current distribution of plant, insects and vertebrate endemic species will be used to validate the location of these refuges.

Methods

Using PMIP 2 data and cost surfaces established taking into account topographical information, we try to establish the most probable location of Mediterranean species in past times (refuges) exploring the degree of concordance between these regions and current endemic regions in the Iberian Peninsula using the information of endemic Iberian species.

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Simulation of Hydrology Regime in North Eurasia during the last 21000 years

People involved: Alexander Kislov, Pavel Toropov (Moscow State University, Russia)

Contact: Alexander Kislov

Aim

We plan to simulate the reaction of the hydrologic regime of East European and West Siberian plains on global climatic changes which took place during last 21000 years, using AGCM and OAGCM outputs.

Methods

We propose:

To study the structure of the hydrological regime in the model outputs from both the pre-industrial model runs and the mid-Holocene runs. To study the structure of the NAO to estimate its contriburion to variation of river runoff regime both for present and paleotime. to study the changes in the Caspian Sea and the Black Sea in the PMIP2 mid-Holocene simulations. Our analysis will focus on comparing the strength of the sea level changes calculating based on the model output, and understanding the causes of any model differences. To assess the realism of simulated northern hemisphere high-latitude climates through comparison of simulated and observed river runoff changes at the LGM.

We will:

1. Compare observed changes in river runoff within the East European Plane and West Siberia Plane with simulated runoff patterns from simulations.
2. Identify for each set of simulations robust patterns amongst the simulations, and responses that are model dependent.
3. Analyse the different drought indexes to help relate the changes in the meteorological fields and river runoff.
4. Examine the causes of the simulated changes in river runoff patterns.
5. Examine the causes of the simulated changes in the Caspian Sea and the Black Sea levels.

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Tropical Cyclone Climatology at LGM and mid-Holocene

People involved: Simon Dadson (Centre for Ecology and Hydrology, Wallingford, UK), Rob Korty, Suzana Camargo (Texas A&M University, College Station, TX, USA), Joe Galewsky, and Sandy Harrison

Contact: Simon Dadson

Aim

We propose to study changes in tropical cyclone climatology in the PMIP2 LGM, mid-Holocene. Model tropical storms have long been studied in low-resolution GCMs (e.g., Manabe et al., 1970, J. Atmos. Sci. 27:580-613), and although current GCMs are still too coarse to resolve tropical cyclones precisely, they do produce features that are similar to modern tropical cyclones with approximately correct climatology (e.g., Camargo and Sobel, 2004; Tellus 56A:56-67). Our analysis will compare the intensity and pattern of tropical cyclones observed in modern GCM simulations with the tropical cyclone climatology observed in LGM, 6 kyr, and planned transient PMIP2 simulations. Our results will be compared with palaeoclimatic observations in lake sediments and pollen, with particular emphasis on the western Pacific.

Methods

1. Identify patterns of tropical-cyclone disturbances in PMIP2 simulations (OA, and OAV) for 21 kyr, 6 kyr, and planned transient simulations, using the method of Camargo and Sobel (2004) and compare with existing results for GCMs applied to modern era.
2. Investigation of model-model variablility and quantification of model uncertainty.
3. Comparison of precipitation amount and intensity with palaeoclimatic observations in lake sediment and pollen, with particular emphasis on western Pacific.

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Evaluating pleistocene refugial predictions for the Perognathus flavus species group using coalescent analyses

People involved: Sean A. Neiswenter and Brett R. Riddle (University of Nevada, Las Vegas)

Contact: Sean A. Neiswenter

Aim

We plan to use niche modelling and pleistocene climate models to predict location and number of potential refugia for a species group of pocket mouse in North America.

Methods

We will test the predicted locations and number using coalescent simulations as well as traditional population genetic and phylogeographic anlyses. Finally, we will evaluate the generality of our predictions using multiple codistributed taxa.

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Impact of past climate changes on freshwater snails range dynamics

People involved: Mathilde Cordellier and Markus Pfenninger (Ecology, Evolution and Diversity Institute, University of Frankfurt, Germany)

Contact: Mathilde Cordellier

Aim

It is a central premise in biogeography that climate exerts a dominant control over the natural distribution of species. Whether and how species ranges will change in the oncoming climate change is becoming of increasing importance. This project aims at critical evaluation of the generally applied hypothesis of intraspecific niche conservatism. This assumption is crucial for the application of bioclimatic projection models to the prediction of future species ranges.

Methods

Suitable refugial areas for the LGM according to the presently occupied climatic niche will be inferred by projecting the presently occupied climatic niche on the reconstructed paleoclimate distribution provided by PMIP2. Molecular phylogeographic methods allow us to infer the actually occupied refugial areas. The congruence or incongruence of the modelled suitable area with inferred refugia shows whether niche conservatism or niche evolution governed the reaction of the model species on the Pleistocene/Holocene climate change.

We use pulmonate freshwater snails as model species because their present day distributions are comparatively well known, and they inhabit all sorts of freshwater habitats. They represent a substantial part of freshwater biodiversity. They occupy a prominent place in the food web of aquatic ecosystems (Woodward & Hildrew, 2002), shaping the community structure of both their food ressources and their numerous predators (Dillon, 2000). Any change in gastropod community structure is therefore likely to have profound effects on the entire freshwater ecosystem (Dillon, 2000). Furthermore, there are reasons to presume that the ranges of these freshwater snails will be seriously affected by a warming climate, as significant range changes could be shown for other gastropod taxa as a result of past climate changes (Pfenninger & Posada, 2002; Wilke & Pfenninger, 2002; Pfenninger et al., 2003).

Published papers

[ 04/25/08 ] [ 04/18/08 ] [ 01/19/09 ]

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Application of inverse methods to the glacial CO2 problem in an OGCM

People involved: Tim DeVries and Francois Primeau (University of California, Irvine)

Contact: Tim DeVries

Aim

We will spin-up a version of the NCOM dynamical ocean model with various sets of LGM surface boundary conditions (SST, SSS, and wind stress). Each unique combination of surface boundary conditions will result in a unique circulation in the dynamical ocean model. With the set of model circulations thus obtained, we can treat the ocean circulation at the LGM as an 'unknown' parameter in subsequent experiments that we will run with coupled biogeochemical and sediment models. One such experiment will be an inverse modeling study of the ocean carbon cycle at the LGM. This experiment aims to better constrain the possible mechanisms (or combinations of mechanisms) that may have been responsible for the low levels of atmospheric CO2 observed at the LGM. For reference to a similar study using a box model, see Legrand and Alverson (Paleoceanography, 16(6), 2001).

Methods

We plan to use output from some of the PMIP-2 models for our surface boundary conditions, particularly wind stress and SSS. For each set of surface boundary conditions, we will spin-up the model until steady-state is reached, extract the time-averaged circulation and eddy diffusivity fields, and create a 'transport operator' that we will use to run experiements offline.

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Vegetation assembly in the postglacial

People involved: Matthias H. Hoffmann (Martin-Luther-Universität Halle-Wittenberg)

Contact: Matthias H. Hoffmann

Aim

Present vegetation communities (associations or higher categories of the Braun-Blanquetian system of plant-sociology) are supposedly assembled newly after the LGM. Alternatively, the communities may have migrated as a `super organism'. Our recent study revealed that the overlay of the general distribution maps of the species contributing to these local communities predicts the geographical extent of this community quite well (M. H. Hoffmann and N. B. Ermakov, Flora, 2008, in press). The Siberian forest communities analysed in this work consist of a mix of Eastern and Western Eurasian species, which may point to different migration histories.

Methods

Using a BIOCLIM approach of the present ranges that may reflect the climatic tolerances of the species and the projection of these data on the modelled climates of the LGM shall reveal whether the species may have co-migrated after the LGM or may have survived in approximately the same area.

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Model representation of global variations in seasonality

People involved: Samantha Burgess and Gideon Henderson (University of Oxford)

Contact: Samantha Burgess

Aim

Compare and contrast the amplitude of seasonal temperature variation of different models at mid and high latitude locations for modern projections and different climate regimes including the mid-Holocene insolation high and the last glacial maximum (LGM). The goal is to identify areas where models presently disagree about past seasonality, and the role that any such disagreement might play in the more general performance of the models. An assessment of regions where past seasonality is uncertain will also help to direct future high-resolution paleoclimate observations.

Methods

We plan to:

1. Develop maps indicating seasonal variability at mid latitude (temperate) and high latitude (polar) locations in both hemispheres for the PMIP models, and maps that highlight areas of disagreement between the models.
2. Examine where the model predicted seasonality disagrees with observational data.
3. Compare the seasonality in models of present-day conditions with modelled projections of the mid Holocene climate at 6000 BP during higher insolation and predicted increased seasonal variability and modelled projections of LGM climate.
4. Develop a global map of predicted seasonal variability during the mid-Holocene and LGM, and compare these maps to the modern seasonality map.
5. Identify regions where PMIP models disagree about past seasonal amplitudes and assess the reasons for and significance of any such disagreements.

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Storm tracks in paleoclimate models

People involved: Lennart Bengtsson, Kevin I. Hodges (University of Reading), Masa Kageyama, Alexandre Laîné (LSCE) and Gwendal Rivière (CNRM/Météo France)

Contact: Lennart Bengtsson

Aim

The aim of this project is to examine the global cyclone activity in paleoclimate models, in particular during the last glacial maximum, Younger Dryas and mid-Holocene to try to understand the nature of the cyclone distribution and properties during these periods, for example the position of the storm tracks relative to the major ice masses.

Methods

Eulerian diagnostics and objective cyclone tracking software will be used (data frequency permitting) to produce storm track diagnostics for the LGM and Mid-Holocene runs. This will contrast two periods where the climate was colder than present and warmer respectively. The nature of the cyclones, location and properties will be explored and their relationship to the major ice masses. Both the NH and SH will be explored.

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Modeling the distributions of animals during the Pleistocene

People involved: Corinne L. Richards (University of Michigan)

Contact: Corinne L. Richards

Aim

To predict how species distributions have changed in response to climate change since the last glacial maximum.

Methods

I will use species distribution modeling techniques to reconstruct the distributions of species during different periods of the Earth's past. To do this, I use species locality data from natural history databases, GIS layers describing climatic parameters important to defining the limits of species' distributions, and a distribution modelling algorithm. The modeling algorithm combines the locality data and the climatic data to predict which areas are suitable for the species of interest. These species distribution models can be projected onto climate estimates from past climates to map the predicted distributions of species during that time period.

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Projecting African plant species distributions into palaeoclimate space

People involved: Colin J. McClean, Jon C. Lovett and Rob Marchant (Environment Department, University of York, UK)

Contact: Colin J. McClean

Aim

Project climate envelope models for African plants species into LGM and MH climate space. Compare projections with fossil pollen records.

Methods

Species-climate envelope models or ecological niche models will be fitted to more than 3000 present-day species distributions of woody plants in Africa. Models for species that can be adequately modelled using a set of variables from the PMIP2 pre-industrial climate will be projected back into LGM and MH climate space to consider climate suitability for these species back in time. The suite of PMIP2 models will be used to give some indication of variation across different climate predictions. Where possible, projections will be compared to fossil records in the African Pollen Database. Potential biogeographic patterns of LGM and MH vegetation will be considered in the light of the present-day distribution of African biodiversity hotspots.

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The role of atmosphere and ocean heat transport in driving polar climate change and variability

People involved: Francesco Pausata, Kerim Nisancioglu, Camille Li (Bjerknes Centre for Climate Research)

Contact: Kerim Nisancioglu

Aim

This subproject is part of the modelling component of a multidisciplinary study called ARCTREC (ARCTic REcords of past climate change - dynamics, feedbacks and processes). In particular, our goal is to understand the role of atmosphere and ocean heat transport in driving polar climate change and variability over a range of climate states.

Methods

We plan to analyze the PMIP2 output to see how heat transport by the atmosphere and ocean differ during LGM and 6ka BP. We will investigate how first-order changes in heat transports in the two climates are related to changes in equator-to-pole temperature gradient and the surface temperature of the polar cap. Furthermore, we will look for relationships between variability in these heat transports and variability in extratropical surface temperature, precipitation and sea ice extent. We will use these results in conjunction with transient simulations from an EMIC (the MIT GCM) to assess how and why the response of the high latitudes is affected by external forcings (orbital forcing, greenhouse gases, land ice in the EMIC simulations) as opposed to feedbacks and processes internal to the climate system (comparing the LGM and 6ka BP time slices in the EMIC and in the PMIP2 simulations).

Published papers

[ 09/11/09 ]

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LGM and mid-Holocene New Zealand climates

People involved: Anthony Fowler, Paul Williams (University of Auckland, New Zealand), Duncan Ackerley, James Renwick, Sam Dean and Brett Mullan (National Institute of Water and Atmospheric Research, Wellington, New Zealand)

Contact: Anthony Fowler

Aim

To inter-compare PMIP2 climate model simulations of atmospheric circulation in the vicinity of New Zealand at the LGM and the mid-Holocene and to compare model results with zonal and meridional circulation indices reconstructed from multiple palaeo proxies.

Methods

1. Analysis of simulated pressure fields from PMIP2 model ensembles to ascertain the level of agreement between models in the New Zealand region, especially with regard to the sensitivity of meridional and zonal flows over New Zealand to known climate forcings.
   
   
2. Reconstruction of LGM and mid-Holocene atmospheric circulation regimes (including zonal and meridional indices) from diverse palaeo proxy records.
   
   
3. Comparison of model and palaeo results to assess model performance and to identify priorities for palaeo research (e.g. key New Zealand climate regions requiring additional work).

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Comparison of simulations of the Arctic Oscillation and Antarctic Oscillation at LGM and mid-Holocene

People involved: Junmei Lu and Seongjoong Kim (Korea Polar Research Institute)

Contact: Junmei Lu

Aim

The subject of this analysis is to investigate the structure of the Arctic Oscillation (AO) and Antarctic Oscillation (AAO) in the different climate. Model outputs from LGM, mid-Holocene and pre-industrial PMIP2 experiments will be compared. The calculation of the AO and AAO indices will be performed through principal component analysis (PCA). The relations between the AO (AAO) and the climate over East Asia under different climate background will also be discussed.

Methods

We plan to:

1. Analyse the spacial structure and the temporal variabilities of the AO and AAO in climate simulations for the pre-industrial, 6ka and 21ka.
   
   
2. Compare variability between models to obtain the combined results about the characteristics of the AO and AAO in different climate period.
   
   
3. Investigate the effects of the pre-industrial, 6ka and 21ka AO (AAO) on Eastasian climate.
   
   
4. Compare the relative contribution of the AO and AAO to the climate anomalies in East Asia under different climate background, for example in Paleoclimatic period and in modern period.

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Tropical oceanic impact on the East Asian Monsoon at LGM and mid-Holocene

People involved: Botao Zhou (National Climate Center, China Meteorological Administration)

Contact: Botao Zhou

Aim

We propose to study the changes in the East Asian monsoon and the tropical ocean on the centurial and interdecadal timescales, using PMIP2 LGM and mid-Holocene simulations. Our analysis will focus on the comparionson between PMIP2 simulations and paleo-geographical records in China, and understanding the relationship between the East Asian monsoon and the tropical ocean at LGM and mid-Holocene.

Methods

Our study will be in three parts:

1. We will analyze the long-term changes of the temperature, precipitation, related atmospheric circulation and oceanic current at LGM and mid-Holocene from various PMIP2 models, and then compare them with the paleo-geographical records in China, in order to assess the simulation ability of models in East Asia and the extent of model-model variability.
   
   
2. Based on the PMIP2 results, we will use different dynamical and thermodynamical indices that indicate the intensity of the present East Asian monsoon to analyze the centurial and interdecadal features of the East Asian monsoon at LGM and mid-Holocene.
   
   
3. We will study the relationships between the East Asian monsoon and the tropical ocean on the centurial and interdecadal timescale at LGM and mid-Holocene, and try to propose the mechanism of their linkage.

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Estimation/Simulation of mid-Holocene temperature gradients

People involved: Basil Davis (University of Newcastle, UK) and Simon Brewer (CEREGE, France)

Contact: Simon Brewer

Aim

We wish to compare observed changes in the latitudinal temperature gradient for the mid-Holocene period with changes simulated by the suite of PMIP/PMIP2 models.

Methods

Changes in the Holocene latitudinal temperature gradient have been estimated using a gridded set of pollen reconstructions (Davis et al.,2003), for a region between 30N and 75N. The results show a strong relationship with the latitudinal insolation gradient during this period. For the mid-Holocene, this has been extended southwards over land by examining temperature reconstructions from tropical Africa, as well as into the marine domain based on SST proxies. We would like to compare these reconstructions with the PMIP/PMIP2 simulations to see if:

1. The observed changes are simulated by the models.
   
   
2. If there is a difference between non-coupled, coupled OA and coupled OAV models in the simulation of these changes.

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Testing hypotheses of population history in multiple codistributed lizard taxa in Hispaniola: the effects of glacial maxima and minima

People involved: Matthew E. Gifford (Washington University in St. Louis, Missouri, USA)

Contact: Matthew E. Gifford

Aim

I plan to use ecological niche modelling of past distributions to assess the potential impact of climate fluctuations on observed genetic structure in three codistributed lizard taxa from the island of Hispaniola.

Methods

I will use data from the LGM and estimated glacial minima (1.5X and 2X CO2 models) in association with coalescent analyses of multiple genetic loci in each species to test hypotheses and asses the impact of these processes at the community scale.

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Assessing the impact of changes in the strength of the southern hemisphere westerlies on atmospheric CO₂ content

People involved: Laurie Menviel, Axel Timmermann, Oliver Timm (University of Hawaii, USA) and Anne Mouchet (Université de Liège, Belgium)

Contact: Laurie Menviel

Aim

The aim of our project is to study the climate as well as marine carbon cycle response to changes in the southern hemisphere westerlies using an Earth system model of Intermediate complexity (LOVECLIM).

Methods

We perform numerical simulations using the fully coupled atmosphere-ocean-seaice-marine carbon cycle model (LOVECLIM). LOVECLIM normally also includes a terrestrial biosphere model, but in order to simplify the simulations, we disactivate it.

Starting from a pre-industrial climate state, we study the climate as well as marine carbon cycle response to:

• a decrease in the strength of the southern hemisphere westerlies.
  
  
• an increase in the strength of the southern hemisphere westerlies.
  
  
• a 10 degree of latitude equatorial shift of the southern hemisphere westerlies.

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Biogeographical studies based on pollen fossil data and machine learning techniques

People involved: José Antonio López Sáez (CSIC, Spain) and Francisca Alba Sánchez (University of Granada,Spain)

Contact: Francisca Alba Sánchez

Aim

The recent advances in computer-based biogeographical species modeling have enabled landscape simulation. Quaternary pollen sequences and machine learning techniques will be connecting to predict species distributions in response to climate change since the last glacial maximum. In this study we will reconstruct the location of the glacial refugia and postglacial spread of different taxa (Abies, Quercus, Pinus, etc.) throughout Europe or Mediterranean basin.

Methods

Geographical Information Systems (GIS), computer-based biogeographical species modeling and pollen fossil sequences are used to reconstruct the distributions of species during different periods of the Earth's past. The Atmospheric General Circulation Models (PMIP2 DB) will provide climate scenarii to establish the most probable location of European species in past times (Last Glacial Maximum and Mid-Holocene).

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Global monsoon and Asian-Australian monsoon system variability on orbital time scale analyses

People involved: Bin Wang (University of Hawaii, USA), Jian Liu (Nanjing Institute of Geography and Limnology, China) and Pascale Braconnot (LSCE, France)

Contact: Bin Wang

Aim

This project aims at improving our understanding of the monsoon precipitation variability on orbital time scale and in the last millennium.

Methods

The major tasks of analysis include the variability of the Asian-Australian monsoon system, the East Asian monsoon subsystem, and the global monsoon system. The variability of these monsoon precipitation and circulation systems on interannual and interdecadal time scales have been or will be analyzed in a parallel fashion using modern records. It is interesting to compare the common and different mechanisms that operate on different time scales. We believe that this effort is fundamental for advancing our monsoon dynamics.

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Climate variability over Scandinavian during the Holocene: comparison between the proxy data and climate modelling

People involved: Qiong Zhang, Hanna Sundqvist, Karin Holmgren, Erland Källén, Heiner Körnich, Anders Moberg and Johan Nilsson (Stockholm University, Sweden)

Contact: Qiong Zhang

Aim

To increase the understanding of climate variability over Scandinavian during the Holocene through integrating proxy data and global climate modelling.

Methods

• Compile and analyse oxygen isotope records from various Holocene proxy archives together with tree-ring density and width records, with a focus on the Scandinavian and surrounding sub-Arctic regions. The obtained pattern will be utilized for discussion the potential of statistical treatments and modelling for explanations of the underlying caused behind the observed proxy data patterns.
  
  
• Analyse simulated variability patterns in 6Ka runs, compare the different model results. The information from simulated climate variability patterns will be used in order to explain and understand reasons for similarities and dissimilarities between the data and model.

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LGM model-data comparison over China

People involved: Dabang Jiang, Xu Yue and Zhongshi Zhang (Institute of Atmospheric Physics, Chinese Academy of Sciences, China)

Contact: Dabang Jiang

Aim

To compare the PMIP1 and PMIP2 model simulations with the multiple palaeo-proxies over Chinese interior and then to advance our understanding of the LGM climate over China.

Methods

1. Delineating the LGM climate scenario over Chinese interior based on a variety of proxies, focusing on surface air temperature and precipiation.
   
   
2. Evaluating the PMIP models' ability to simulate the present climatology over China and then analyzing multil-model results stemming from the PMIP1 and PMIP2.
   
   
3. Quantifying the extent of accordance between the models and proxy estimates and exploring the potential reasons responsible for the discrepancies.

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The role of historic and present climate in determining contemporary patterns of ant species richness in North America

People involved: Matthew C Fitzpatrick, Nathan J. Sanders, JP Lessard (University of Tennessee, Knoxville, USA), Robert R. Dunn (North Carolina State University, USA) and Michael D. Weiser (University of Arizona, USA)

Contact: Matthew C Fitzpatrick

Aim

Several recent studies have detected a signal of historic climate on present-day patterns of biodiversity, including both plants and vertebrates. We will explore the relative importance of historic and present-day climate in determining current patterns of biodiversity in an ecologically-important invertebrate - ants. More broadly, we are interested in determining the stability of species-climate relationships across space in time in the context of modeling responses of ants to future climate change.

Methods

We will use a variety of modeling techniques (niche-based models, GLM's, generalized dissimilarity modeling, etc), PMIP 2 and contemporary climate datasets, and a comprehensive database of North American ant distributions to investigate to the ability of historic and contemporary climate to predict patterns of species richness and turnover and distributions of ants.

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Tropospheric jets and North African climate

People involved: Sharon Nicholson (Florida State University, USA) and Bette Otto-Bliesner (NCAR, USA)

Contact: Sharon Nicholson

Aim

To understand the roles of the tropospheric jets: the African Easterly Jet (AEJ) of the mid-troposphere and the Tropical Easterly Jet (TEJ) of the upper-troposphere in explaining changes in rainfall over North Africa at 6 ka and LGM.

Methods

1. Analyze the PMIP2 simulations for preindustrial, 6 ka, and LGM in terms of seasonal locations and intensities of the AEJ and TEJ.
   
   
2. Investigate how changes in these tropospheric jets are related to surface changes, over the land and oceans.

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Palaeo-distribution of the cloud forests in Mexico

People involved: Rocio Ponce (University of Queensland, Australia), Bob Pressey and Stephen Williams (James Cook University, Australia)

Contact: Rocio Ponce

Aim

Estimate the extension, connectivity and isolation indices (e.g. frequency of separation, proportion of time separated) of cloud forests in the Sierra de Juarez, Mexico since the last glacial maximum (21,000 BP) and 6,000 BP.

Methods

Using PMIP data and species records model the distribution of Mexican TMCF in the Sierra Juarez in Oaxaca. Then, derive indices of isolation (e.g. frequency of separation, proportion of time separated), extension and connectivity of the fragments.

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Ecological niche analysis, molecular phylogeography and predictive modelling of past distributions of mangrove ecosystems

People involved: Richard Dodd and Zara Rafii (University of California, Berkeley, USA)

Contact: Richard Dodd

Aim

To model distributions of species of mangrove plant at LGM and mid-Holocene.

Methods

We will use ecological envelope modeling to estimate current physiological limits of mangrove plant species. We will then estimate distributions at 6000ybp and LGM. Climate and coastal geomorphology changes will be used to estimate past distributions. Molecular data will be used to confirm possible refugia and sites of colonization.

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Comparative phylogeography and speciation history of tetraploid Cyanus species

People involved: Carsten Löser and Frank H. Hellwig (Friedrich-Schiller-Universität Jena, Institut für Spezielle Botanik, Germany)

Contact: Carsten Löser

Aim

Pleistocene glaciations are thought to be a major promotor for the repeated evolution of polyploidy in European plant species. Tetraploid Cyanus (Centaurea s.l.) species are found in the northern margin of the genus' distribution and are ecologically differentiated from their presumed diploid ancestors. By tracking their multiple origins, we want to identify the historical background and common factors facilitating tetraploid establishment and dispersal.

Methods

Comparative molecular phylogeographic analyses are carried out to characterize the current geographical structure of shared genetic variation between tetraploid species and their presumed diploid ancestors. We want to apply ecological niche modeling projected on climatic conditions in the LGM and MH to find accordance of past distribution with genetically defined lineages.

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Current and past determinants of Western Palearctic biodiversity

People involved: Joaquín Hortal (NERC Centre for Population Biology, Imperial College London, UK) and other researchers

Contact: Joaquín Hortal

Aim

Knowing and understanding how biodiversity has been affected by past environmental changes is central to forecast its response to the changes expected in the future. Past and current effects on biodiversity are currently under debate, a debate particularly interesting at the Western Palearctic, where regional topographic particularities and a complex history have resulted in a heterogeneous distribution of biodiversity. The general idea of this working group is to:

1. reformulate the hypothesis about the distribution of biodiversity within a spatial framework were these hypotheses can be tested against data on the distribution of biodiversity in a formal way.
   
   
2. determine which part of current distribution of biodiversity is strictly related to current responses to the environment, and which part is total or partially affected by past events and past environmental condition.

Methods

We will put together a number of relevant specialists (including first-order specialists and some postdocs working in Past and Present Western Palearctic Biogeography and/or climate change) and data to formulate the hypotheses and develop the subsequent analyses throughout a series of workshops. Biodiversity data will include:

1. Accurate data on the current distribution of an important number of groups (including vertebrates, invertebrates and plants).
   
   
2. Palaeontological data about the distribution and communities of (at least) mammals and plants.

Maps of the outputs of the different hypotheses will be constructed using data on present and past climate and land cover (partially based in PMIP 2 data).

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Intercomparison of subduction rates changes in different climatic periods

People involved: Ilana Wainer and collaborators (University of São Paulo, Brazil)

Contact: Ilana Wainer

Aim

Water mass formation in the South Atlantic is an important component of ocean ventilation in the southern hemisphere. For example, components of Subantarctic Mode ater (SAMW) and Antarctic Intermediate Water (AAIW) are formed in this basin, and much of the Antarctic Bottom Water is formed in the Weddell Sea. This region is important because it takes up a lot of heat and carbon dioxide from the atmosphere. Therefore, an important question is how water mass formation changed over the Holocene.

Methods

PMIP model results for 6K BP and 21K BP will be used to analyse changes in water mass subduction rates in the South Atlantic. The model results for the present day will becompared to observations.

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Seasonality changes in the Red Sea region during LGM, Holocene and present-day conditions

People involved: Marcus Herold, Gerrit Lohmann and Thomas Laepple (Alfred Wegener Institute for Polar and Marine Research, Germany)

Contact: Marcus Herold

Aim

Seasonal variation of rainbelt position over the African continent as well as Northern-Hemisphere circulation patterns determine amount and isotopic composition of the Red Sea hydrology. In this modeling study, we investigate impacts of extreme climatic conditions on the isotopic rainfall composition. The focus is on the seasonality changes of the isotopic signals which we relate to anomalies in temperature, precipitation and moisture advection. The results are compared to high-resolution proxy archives such as corals and speleothems from that region.

Methods

An isotope-enabled version of the ECHAM Atmospheric GCM will be used to determine changes in the hydrological cycle over North-East Africa in glacial and interglacial maxima. SST and vegetation from PMIP2 OAV simulations will serve as boundary conditions and will allow validation of our results. Relative contributions of anomalies in temperature and amount of rainfall are estimated within the physically consistent model setup.

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Mean climate state - ENSO relationships in the mid Holocene and LGM

People involved: Soon-Il An (Yonsei University, Korea)

Contact: Soon-Il An

Aim

The ENSO characteristics are generally determined by the tropical mean climate state, and thus they might be different under the different climate conditions such as mid-Holocene and the LGM conditions. Therefore, the aim of the study is to investigate the relationship between the mean climate state and ENSO to the mid-Holocene and the LGM conditions and to understand the related dynamics.

Methods

1. First of all, the relationships between ENSO characteristics (i.e., amplitude, skewness, propagation characteristics, and etc) and the mean climate state are investigated using PMIP data.
   
   
2. In next step, in order to find the main components of the mean climate state in modifying ENSO, the eigen analysis of a linearized intermediate coupled ocean-atmosphere model will be performed (An et al. 2004), in which the mean climate state obtaining from PMIP are incorporated into the model.

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Ecology and evolution of Great Basin scorpions

People involved: Matthew Graham, Jef Jaeger and Brett Riddle (University of Nevada, Las Vegas, USA)

Contact: Matthew Graham

Aim

We are conducting a comparative phylogeographic assessment of several scorpion species occupying the Great Basin Desert and surrounding regions. The target species represent several families and genera, and because each species has a unique ecology and potentially distinct physiological requirements, we aim to develop insight into differential responses to historical climate change.

Methods

Our plan is to use ecological niche modeling to develop a better understanding of the current habitats occupied by these scorpions and to combine this with paleoclimatic data to model potential historical distributions. These models will provide independent hypotheses about changes in population structures of these species since the last glacial maximum. We will first, however, use these models as guides in developing genetic sampling strategies.

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Population structure and landscape genetics of Ascaphus montanus (Rocky Mountain tailed frog)

People involved: Christopher Drummond (University of Idaho, USA)

Contact: Christopher Drummond

Aim

The aim of this project is to evaluate the contribution of contemporary and LGM landscapes to patterns of genetic variation and connectivity in an endemic amphibian from northwestern North America.

Methods

Contemporary and LGM climatological data will be used to predict habitat suitability using ecological niche models based on georeferenced collection localities. Resistance surfaces derived from a combination of niche models and electronic circuit theory will be used to test hypotheses related to the role of different landscape features in determining observed patterns of microsatellite DNA variation.

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Using current and past climate and distribution data to model the future distribution of the North American Pika (Ochotona princeps)

People involved: Scott Loarie (Duke University, USA)

Contact: Scott Loarie

Aim

I wish to project the impact of climate change on the distribution of the North American Pika. Traditional species response to climate change studies rely on niche models that model current species distributions as a function of current climate to predict future distributions from future climate. These methods have been criticized since models based on past climate and distribution data often poorly predict current distributions (M.B. Araújo and C. Rahbek, 2006, Science). I propose to build a model that predicts the future Pika distribution as a function of future climate, current climate and distribution data, and past climate and distribution data and compare it to the traditional approach described above.

Methods

As in Waltari et al. 2007, PloS One, I will derive past and future climate data from the CCSM and statistically downscale them using the WorldClim dataset. I will gather past Pika distribution data from Grayson, 2005, Journal of Biogeography, and current distribution data from the Global Biodiversity Information Facility. I will use Maxent to model the Pika distribution as a function of climate using both past and current climate and distribution data. I will then project this model into future climate projections in order to model the future Pika distribution.

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Comparative phylogeography and speciation history of widespread anurans in the Brazilian Atlantic Forest

People involved: João Alexandrino (Universidade Estadual Paulista - Rio Claro, SP, Brazil)

Contact: João Alexandrino

Aim

Pleistocene glaciations are thought to be a major promotor for biological diversification in temperate northern hemisphere biotas. We here propose a phylogeographical study of anuran species widely distributed in the Brazilian Atlantic Forest.

Methods

By using amphibians as model organisms, we will

• collect and compare mitochondrial and nuclear DNA data from multiple populations of forest-associated amphibian species,
• and use the tools of comparative phylogeography and phylogenetics combined with paleoclimate modeling to study patterns of biological diversity and to test hypotheses about their causal processes in the poorly known Brazilian Atlantic forest.

The 0K, 6K and 21K data will provide clues into the spatio-temporal dynamics of organismal geographic distributions (through ecological modelling). The LGM data will specifically be used as a coarse surrogate of the geographic distribution of organisms during glacial cycles, given such climatic oscilations were intermitent during the Quaternary and part of the Tertiary. More specifically, predicted organismal historical distributions can be compared with phylogeographic data to infer processes such as vicariance and range expansions since the last glaciation.

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LGM and mid-Holocene climate over Central Asia: comparison between the proxy data and modeling results

People involved: Jin Liya, Youbing Peng and Liangliang Wang (Lanzhou University, China)

Contact: Jin Liya

Aim

To increase the understanding of climate variability over Central Asia at LGM and mid-Holocene via integrating proxy data and global climate modelling.

Methods

• Central Asia is a sensitive area in the mid-latitude Northern Hemisphere where the westerly winds and/or westerly-related planetary fronts and their associated jet streams are active. It is of interesting to check the phase relationship between the westerlies and the Asian monsoons by analyzing the PMIP1 and PMIP2 model results at LGM and mid-Holocene, with a focus on the differences and similarities between Central Asia and East Asia.
• Comparison of model and integrating proxy data over Central Asia, to assess model performance and to interpreter the potential mechanisms underlying LGM and mid-Holocene climate variability.

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The role of oceanic surface wind-stresses in the glacial meridional overturning circulation

People involved: Marisa Montoya (Universidad Complutense de Madrid, Spain)

Contact: Marisa Montoya

Aim

One of the quantities showing the largest spread among models simulating the climate of the last glacial maximum is the Atlantic meridional overturning circulation (AMOC). PMIP2 models show a range of +/-40% in the deviations with respect to the Holocene in the simulated LGM AMOC strength in nine coupled climate models [Weber et al., 2007]. Here we aim to establish to which extent the former discrepancies might be due to differences in the simulated surface winds.

Methods

Analyze the relationship between the response of glacial surface wind stresses in different latitudes and the response of the meridional overturning circulation as simulated in the PMIP2 runs.

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Differences of the Hadley circulation between the mid holocene and present

People involved: Weiye Yao and Yongyun Hu (Peking University, Beijing, China)

Contact: Weiye Yao

Aim

Study climate changes through the variation of Hadley circulation between the mid holocene and present.

Methods

Study the intensity and width variation of Hadley circulation by calculating the mass stream function.

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Tropical ITCZ and Walker circulation in paleoclimate

People involved: Jialin Lin (Ohio State University, USA)

Contact: Jialin Lin

Aim

We will examine the intertropical convergence zones (ITCZ) and Walker circulation in PMIP2 LGM, Mid-Holocene and Pre-industrial simulations, especially the ocean-atmosphere feedback mechanisms determining the tropical mean state in paleoclimate.

Methods

• The ocean-atmosphere feedback parameters will be analyzed using the methods of Lin (2007).
• The Walker circulation will be studied following the methods of Lin et al. (2008).

References:

• Lin, J. L., 2007: The double-ITCZ problem in IPCC AR4 coupled GCMs: Ocean-atmosphere feedback analysis. J. Climate, 20, 4497-4525.
• Lin, J. L., B. E. Mapes, and W. Han, 2008: What are the sources of mechanical damping in Matsuno-Gill type models? J. Climate, 21, 165-179.

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Tropical intraseasonal variability in paleoclimate

People involved: Jialin Lin (Ohio State University, USA)

Contact: Jialin Lin

Aim

We will examine the tropical intraseasonal variability in PMIP2 LGM, Mid-Holocene and Pre-industrial simulations. The modes to be studied include the Madden-Julian Oscillation (MJO), convectively coupled equatorial waves, and other subseasonal modes associated with Asian monsoon and North American monsoon. The results will be compared with the current climate, and the physical reasons for any differences will be studied.

Methods

• We will analyze the daily outputs from multiple models.
• The dominant tropical intraseasonal modes will be identified using the methods of Lin et al. (2006, 2008a,b).

References:

• Lin, J. L., G.N. Kiladis, B.E. Mapes, K.M. Weickmann, K.R. Sperber, W.Y. Lin, M. Wheeler, S.D. Schubert, A. Del Genio, L.J. Donner, S. Emori, J.-F. Gueremy, F. Hourdin, P.J. Rasch, E. Roeckner, and J.F. Scinocca, 2006: Tropical intraseasonal variability in 14 IPCC AR4 climate models. Part I: Convective signals. J. Climate, 19, 2665-2690.
• Lin, J. L., K.M. Weickmann, G.N. Kiladis, B.E. Mapes, S.D. Schubert, M. J. Suarez, J. Bacmeister, and M.-I. Lee, 2008a: Subseasonal variability associated with Asian summer monsoon simulated by 14 IPCC AR4 coupled GCMs. J. Climate, in press.
• Lin, J. L., B.E. Mapes, K.M. Weickmann, G.N. Kiladis, S.D. Schubert, M. J. Suarez, J. Bacmeister, and M.-I. Lee, 2008b: North American monsoon and convectively coupled equatorial waves simulated by IPCC AR4 coupled GCMs. J. Climate, in press.

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From past to future: role of climate change in the hybridization dynamics of European ash trees (Fraxinus spp. Oleaceae)

People involved: Juan F. Fernandez-M., Nathalie Frascaria-Lacoste, Pierre Gerard and Damien Hinsinger (Université Paris 11, Orsay, France)

Contact: Juan F. Fernandez-M.

Aim

Western European ashes (Fraxinus excelsior, F. angustifolia and known hybrid zones) are important forest tree species that have experienced large post-glacial expansions as evidenced by pollen and macrofossil data. However, except for some areas, little is known about the actual distribution and origin of hybrid zones in the group. Moreover, hybridization in these close species appears as introgression of the Mediterranean type (F. angustifolia) onto the more Atlantic eco-type of F. excelsior raising serious concerns about the genetic integrity of both species in a changing climate. Thus, these ash species represent a very useful model to examine the interaction between climate, migration and adaptation.

We propose to evaluate the potential distributions of these species during the Last Glacial Maxima and the Mid Holocene to: a) determine the origin of hybrid zones; b) to detect geographic areas of strong historical climate selection with respect to the present distribution; and c) to evaluate whether global warming would modify or produce new areas of hybridization.

Populations detected in zones with a history of high climatic selection will be used in parallel ongoing projects of phylogeographic patterns and candidate gene variation. Also, we intend to help resource managers to design forest conservation and climate mitigation/adaptation plans.

Methods

• We will use species distribution models to infer the distribution of Fraxinus excelsior, F. angustifolia and potential hybrid zones that remain largely unknown for the present climate, using data from our own collections and public databases.
• We will project present day distributions on past climate simulations (LGM and Holocene from the PMIP 2 models) and estimate the degree of historical overlapping (putative hybrid zones) with respect to known paleo-ecological data.
• Next, we will examine future climate scenarios on current species distributions and compare them with historic climate patterns to detect areas of increased hybridization opportunities and/or increased tolerance to climate change.

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Tropical ocean vertical diffusivity

People involved: David M. Anderson, Haui-min Zhang (NOAA NCDC, Boulder, CO, USA)

Contact: David M. Anderson

Aim

We have made some proxy data based calculations of the vertical diffusivity required to balance the tropical ocean heat budget (using the isotherm bowl or bubble approach). We would like to compare this with model simulations for the LGM. Method- Two parts.

Methods

• Calculate the heat budget using the isotherm bowl approach.
• Calculate the discrepancy in LGM cooling between paleo data and model simulations, and determine changes in vertical diffusivity needed to explain this difference.

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Assessing the timing, extent and volume of Tibetan Plateau ice during the last 130,000 years by numerical simulations: A model for interpreting its Quaternary glacial history

People involved: Nina Kirchner, Arjen Stroeven (Stockholm University, Sweden) and Ralf Greve (Hokkaido University, Japan)

Contact: Nina Kirchner

Aim

The Tibetan Plateau is a topographic feature of extraordinary dimension and has an important impact on regional and global climate. Yet, the glacial history of the Tibetan Plateau, in spite of its proposed significance for climate change, has been much less investigated than other formerly glaciated regions in the northern hemisphere, be it through field studies or by numerical simulations.

For example, there are numerous simulations with advanced ice sheet models available for the Laurentide Ice Sheet and the Fennoscandian Ice Sheet. Ice sheet modeling experiments focusing on the entire northern hemisphere also include reconstructions for the Tibetan Plateau, but they typically suffer from limited resolution and frequently overpredict especially present ice volumes on the Tibetan Plateau. At the same time, the majority of field evidence seems to suggest that there has been no plateau-scale glaciation on the Tibetan Plateau during the last glacial cycle.

This might explain why ice sheet modeling experiments focusing specifically on the Tibetan Plateau are rare. Among those existing, even fewer distinguish between precipitation and temperature as boundary conditionsHowever, the issue of a numerical reconstruction of the glacial history of the Plateau remains: it is the topic of this project. We shall use a well-established numerical ice sheet code (SICOPOLIS) which shall be driven by an ensemble of PMIP climatic outputs and which shall reconstruct glacial/non-glacial configurations on the Tibetan Plateauduring the last 130,000 years in terms of possible locations, extends and volumes of ice.

Methods

Preliminary numerical investigations carried out by Kirchner & Greve have indicated that the existence of a Tibetan Ice Sheet is primarily dependent on its mass balance formulation; inherent ice-dynamic processes contribute to a much lesser extent to its existence or non-existence. To further investigate the issue, we will:

• use the present-day topography of the Tibetan Plateau and force the numerical ice-sheet model with an ensemble of glacial/interglacial climates to examine under which circumstances an ice sheet forms, and where ice sheet nuclei are located.
• run paleoclimatic simulations covering the time span from 130,000 years ago until today for an ensemble of PMIP climatic outputs.
• evaluate the effect of different climatic forcings as provided by the PMIP ensemble on the numerical results at selected time slices, e.g., 65,000 years ago, 21,000 years ago, 18,000 years ago, 11,000 years ago and at present.
• evaluate the degree of success of different model runs by comparing simulated timing, extension and ice volume over the past 130,000 years with evidence for ice extent and timing from glacial geomorphological and chronological studies for selected regions of the Tibetan Plateau.

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Paleopermafrost distributions and subsurface hydrothermal regimes

People involved: Kazuyuki Saito, Vladimir Romanovsky, Kenji Yoshikawa, Sergey S. Marchenko, Nancy Bigelow and John Walsh (University of Alaska Fairbanks, USA)

Contact: Kazuyuki Saito

Aim

To calculate the distribution of the frozen ground (permafrost, seasonally-frozen ground) calculated off-line using the forcing terms obtained from different models under the PMIP2 LGM, mid-Holocene, and pre-industrial environment, and compare the results with the paleopermafrost data. We will also examine the relative importance of Ocean-Atmosphere, vegetation, and terrestrial physical components for hydro-thermal regime simulations.

Methods

We plan to:

• calculate off-line the subsurface hydrothermal regimes and the frozen ground distribution with a terrestrial physical scheme under LGM, mid-Holocene and pre-industrial environment, using the forcing terms obtained as outputs form different models.
• compare the results with proxy data and/or reconstructed paleopermafrost maps (e.g. Frenzel, Pecsi, and Velichko (eds.), 1992).
• investigate the across-model, across-component differences by comparing the results obtained by different level of uncoupled-ness (e.g. SST-forced, atmosphere-forced), and land surface conditions (e.g. OA vs. OAV, different soil distribution, complexity of terrestrial physical scheme).

Extra information

Model output variables from OA and OAV runs we will use as forcing and boundary condition data for uncoupled (offline) simulations will include:

• Atmospheric run: sea surface temperature, sea ice concentration, land/sea/ice mask, vegetation type, surface altitude (incl. ice sheets).
• Land surface run: wind, temperature, humidity at the lowest atmospheric level. Atmospheric pressure, rate of precipitation and snowfall, downward radiation of short- and longwave at the surface, and snow accumulation. Overall cloud cover, and land/sea/ice mask.

Published papers

[ 06/30/09 ]

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Effects of CO₂ on biome distributions: modelling variations in n-alkane δ¹³C between the last glacial maximum and Holocene

People involved: Fran Bragg, Colin Prentice and Pru Foster (University of Bristol, UK)

Contact: Fran Bragg

Aim

To determine whether application of climate change alone is sufficient to predict biome shift in Africa at the Last Glacial Maximum (LGM) and mid-Holocene (MH) or whether the effect of CO₂ on plant physiology must be taken into account to obtain the palaeo-biomes. Specifically, to determine the competitive balance between C3 and C4 vegetation, which is apparent in the differential ¹³C fractionation through the different photosynthetic pathways.

Methods

• Apply model deltas (LGM-modern and MH-modern) from each PMIP II model to modern measured climate.
• Feed these climate data into BIOME4 to create vegetation maps for Africa at the LGM and mid-Holocene. Each experiment repeated twice, with modern levels of CO₂ and with palaeo levels.
• Extract carbon isotope output from BIOME4 and compare with δ¹³C data from west African marine cores.
• Compare predicted biomes with palaeo reconstructions.

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Analysis of biological carbon pumps during LGM

People involved: Takamitsu Ito (Colorado State University, Fort Collins, CO, USA)

Contact: Takamitsu Ito

Aim

The goal of this project is to evaluate the role of ocean biological carbon pumps in the lowering of atmospheric pCO2 using a new theory that the impact of biological carbon sequestration can be effectively quantified using the concept of preformed nutrient. Our primary focus will be:

• to simulate the global distribution of preformed carbon, phosphate and alkalinity under LGM and Holocene conditions
• to identify what physical and biogeochemical processes control their inventories
• to quantitatively assess possible range of atmospheric pCO2 change due to fluctuations in ocean biological pumps

Methods

We have developed the new theory of ocean carbon pumps (Ito and Follows, 2005, J Mar. Res.), which has three critical advantages over the conventional view of ocean carbon pumps (i.e. global vertical gradient of DIC) that

• the preformed properties provide quantitative measure of the steady-state atmospheric pCO2
• the preformed properties are conservative tracers and easy to include in numerical ocean models
• the theory brings conceptual box models and GCMs into an excellent agreement

Here, we propose to use LGM and Holocene air-sea buoyancy, momentum fluxes, sea-ice concentration and wind speed from the PMIP2 coupled models to drive a coupled ocean circulation and biogeochemistry/ecosystem model including a well-mixed atmospheric carbon reservoir (Dutkiewicz et al. 2005, Global Biogeochem. Cycles). In particular, we are interested in the role of ocean circulation and sea ice along with changes in iron deposition by executing a suite of sensitivity experiments. In order to illustrate the modeled carbon dynamics in the numerical model, preformed carbon, nutrient and alkalinity are built into the model as diagnostic, passive tracers, which will allow us to quantitatively assess the causes of simulated atmospheric pCO2 change.

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Trends in paleo climate simulations

People involved: Jenny Brandefelt (KTH-Royal Institute of Technology, Stockholm, Sweden) and Bette Otto-Bliesner (NCAR, Boulder, CO, USA)

Contact: Jenny Brandefelt

Aim

We analyse the equilibriation of a 1256 year LGM simulation with CCSM3. To compare this simulation to the other PMIP2 simulations of the LGM, we want to determine the trends in the global annual mean surface temperature for the last 50-100 years of the LGM and Pre-Industrial simulations.

Methods

Linear trends of global annual mean surface temperature.

Published papers

[ 10/13/09 ]

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Climate change as a driver of extinction for Caribbean mammals

People involved: Liliana M. Davalos (Stony Brook University, Stony Brook, NY, USA) and Amy Russell (Grand Valley State University, Allendale, MI, USA)

Contact: Liliana M. Davalos

Aim

To quantify the impacts of climate change on Caribbean mammal extinction.

Methods

We will use environmental niche models projected onto GCMs to estimate the availability of suitable habitat for Caribbean mammals at the LGM and mid-Holocene, and analyze it with respect to current conditions. Estimated changes will then be compared to changes in population size inferred from genetics.

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Role of global ice volume changes in the evolutionary response of Asian monsoon

People involved: Zhengguo Shi and Xiaodong Liu (Institute of Earth Environment, Chinese Academy of Sciences, China)

Contact: Zhengguo Shi

Aim

We propose to explore the effects of global ice volume changes on the response of Asian monsoon system. Our analysis will focus on the regional feature differences and potential mechanisms in the Asian monsoon evolution.

Methods

Our study mainly contains 2 parts, as follows:

• Comparisons of geological climatic records intend to show various changes in the Asian monsoon region during glacial cycles.
• Model outputs will be applied to analyze the effects of global ice volume on Asian monsoon during LGM, especially the regional response differences. Vegetation covers and orbital-induced insolation will be also considered as factors. The potential mechanisms are to be indicated to help explain and understand the distinct responses in the Asian monsoon region.

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Quaternary climate oscillations and the contemporary geographic range sizes of mammals

People involved: Jonathan Davies (University of California, Santa Barbara, USA), John Gittleman (University of Georgia, Athens, USA) and Andy Purvis (Imperial College, London, UK)

Contact: Jonathan Davies

Aim

We will evaluate the impact of Quaternary climate oscillations on contemporary mammalian geographic range size and specificity.

Methods

Large oscillations in Quaternary climate may have favoured habitat generalists, capable of occupying a broad spectrum of habitat types, and hence species predisposed to broad geographic ranges. Alternatively, the relationship between Quaternary climate and range size may be direct, for example, large-ranged species may be composed of a greater number of individuals, providing a buffer against heightened demographic stochasticity during periods of environmental instability. We will use differences between sister species to explore how range size and habitat specificity correlate with the magnitude of climate change since the last glacial maximum.

Published papers

[ 07/23/09 ]

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Last Glacial Maximum dune activity in the Kalahari Desert of southern Africa: observations and simulations

People involved: Brian Chase (School of Geography and the Environment, Oxford, UK) and Simon Brewer

Contact: Brian Chase

Aim

A comparison of aeolian sediment records with simulated dune activity index for the Last Glacial Maximum.

Methods

It has long been understood that as ephemeral landscape features sand dunes are highly sensitive to environmental change, and thus their distribution and the timing of their development may provide clues to past climate dynamics. The relationship between climate and dune activity, however, is neither simple nor straightforward, with a range of controls affecting the balance between erodibility (the availability of sediment for deflation) and erosivity (the potential for sediment transport).

This study will calculate the potential for dune reactivation in southern Africa during the Last Glacial Maximum (LGM, 18 - 24 ka) using output from coupled Ocean-Atmosphere GCMs for 21 ka together with the most detailed DAI equation presently available. This will then be compared to the aeolian sediment records from the region, allowing the following points to be addressed: 1) the reliability of the model outputs over this region, 2) the degree to which DAIs are able to account for the complexity and dynamics of aeolian systems, and 3) the interpretation of dune records as palaeoclimatic proxies at millennial timescales.

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An assessment of the genetic structure and long-term persistence of the montane vole, Microtus montanus, in North America

People involved: Dolly L. Crawford (University of New Mexico, Albuquerque, NM, USA)

Contact: Dolly L. Crawford

Aim

The montane vole is a key member of the New Mexico riparian community. Several factors increase its extinction risk. Like other montane taxa, the montane vole is small, dispersal limited, characterized by isolated populations, and demonstrates an affinity for montane meadows (Findley and Jones, 1962), one of the most endangered habitats in the American west. To understand how future climate and/or habitat change will influence the distribution of the montane vole, a methodology that includes an analysis of its past distribution is significant in several ways.

Methods

I will apply an ecological modeling approach to quantify abiotic factors integral to the species distribution, and the interplay of abiotic factors in the extinction dynamics of the montane vole. An approach that incorporates paleodistribution modeling is a productive way to reconstruct the colonization history of a taxon, especially when combined with genetic data (Hugall et al., 2002). The incorporation of paleodistribution modeling into phylogeographic analyses provides a venue by which results are interpreted in a much broader ecological context. Despite the potential complexities of paleodistribution approaches, the models generated from these analyses provide a baseline against which present and future changes may be measured.

I will use the PMIP2 database to construct the paleodistribution models. This database, which includes coupled ocean-atmosphere dynamics for the Last Glacial Maximum (LGM), is vital to understanding the determinants of the montane vole distribution and testing hypotheses related to how this distribution may change over time.

Construction of the paleomodel will involve several steps. First, I have developed a model of the current ecological envelope for the species in western North America using 800 locality records downloaded from museum databases and those I have recorded from field surveys. Using a GIS, this data is projected onto raster datasets of current ecological conditions, such as rainfall and temperature. For this study, I have used the wORLDCLIM data (Hijimans et al., 2005), land cover (http://glcf.umiacs.umd.edu/data/landcover/), and soil cover (CONUS Soil Database at http://gcmd.nasa.gov/records/GCMD_PSU_CONUS_SOIL.html). In addition to contemporary niche occupied by the species, I have also constructed a probability surface of the species future distribution by projecting current conditions onto the future scenario using MAXENT (Philips et al., 2006). Results from models of present and future conditions using MAXENT and BIOCLIM (Busby, 1991) are similar. Construction of the paleomodel will follow similar steps. Data layers from the LGM are downloaded from PMIP2 website. The data layers are interpolated using the spline function in a GIS to the same resolution as the WORLDCLIM data. Once interpolated, the LGM data is projected onto the species distribution.

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Distribution of novel and analogous climates across space and time

People involved: Linda Beaumont (Plant-Insect Climate Change Ecology Lab, Macquarie University, Australia), Andrew Pitman, Wilfried Thuiller, Niklaus Zimmermann and Nigel Yoccoz

Contact: Linda Beaumont

Aim

The shift of climatic zones and appearance of novel climates has important implications for responses of biodiversity to climate change. We will assess global spatial patterns of novel and analogous conditions across past, present and future climates.

Methods

We will use novel statistical approaches to calculate the similarity across climate variables for consecutive time periods.

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Comparative phylogeography of neotropical trees

People involved: Monica Poelchau and Jim Hamrick (University of Georgia, Athens, USA)

Contact: Monica Poelchau

Aim

To compare phylogeographic data of three Central American tree species with their reconstructed distributions during the last glacial maximum.

Methods

I will model the ecological niches of three neotropical tree species based on their current distribution records, using the distribution modeling program Maxent, and bioclimatic variables described in Worldclim (http://www.worldclim.org/). I will use output from the CCSM and MIROC models at 21 K to reconstruct the species' past distributions based on their current modeled environmental tolerances. These distributions will then be compared to previous hypotheses of Central American rain forest refugia, and will inform further analyses of phylogeographic data already collected for these species in this area.

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What can be learnt from the O17-excess of Antarctic snow?

People involved: Camille Risi (LMD, Paris, France) and Amaelle Landais (LSCE, Gif-sur-Yvette, France)

Contact: Camille Risi

Aim

The O17-excess measured in ice cores is a new and promising isotopic tracor of past climate changes and especially of the climate of the source evaporative regions. Its interpretation is however very limited now and based only on simple rayleigh distillation model [Landais et al., GRL, 2008]. In our study, we use more sophisticated isotopic model in order to:

1. understand what controls the O17-excess tracor. In particular, what causes the observed glacial-interglacial shift in O17-excess of Antarctic snow?
2. infer the maximum information on glacial climate from combined measurements of O17-excess, d-excess and d18O in ice core.

Methods

With respect to the PMIP2 simulations outputs, the goal is to:

1. confront with GCM simulations our estimations of relative humidity and temperature based on isotopic measurements (O17-excess, d-excess, deltaO18) in Antarctic snow;
2. evaluate the uncertainties of our estimations due to processes such as temperature seasonality in Antarctica or evaporative recharge along trajectories.

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Historic distribution of Sistrurus rattlesnakes in North America

People involved: H. Lisle Gibbs and Jessica Wooten (Franklin University, Columbus, OH, USA)

Contact: Jessica Wooten

Aim

To gain a better understanding of the historical distribution patterns and potential Pleistocene refugia for the six subspecies of Sistrurus rattlesnakes in North American using paleo-climate data.

Methods

In order to generate historic distribution patterns for these rattlesnakes in North America, we will use PMIP2 data to simulate these patterns of biodiversity. We aim to analyze these historic models in relation to the current patterns of distribution and DNA-based phylogeographic information for Sistrurus.

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The influence of climate changes during the last glacial period on the population genetic variation of tree species in the East Asia

People involved: Shota Sakaguchi, Michimasa Yamasaki, Yuji Isagi (Kyoto University, Japan) and Shogo Sakurai (Kyoto Prefectural University, Japan)

Contact: Shota Sakaguchi

Aim

We are planning to elucidate the population genetic variation of a tree species (Kalopanax septemlobus) which distributes in the East Asia region. Tree species members that belong to the warm-temperate forests would have experienced recurrent range expansions and reductions under great climate changes during the last glacial period. Thus, it is expected that the population genetic variation would have also influenced by the past climate changes. We can explain the present genetic variation pattern of the tree with scarce fossil records in the East Asia by estimating the past species range and potential refugia.

Methods

1. Elucidate the genetic variation throughout the species range using highly polymorphic genetic markers.
2. Construct the ecological niche models of the target species as a function of major climate variables.
3. Predict the species range and potential refusia under those paleoclimates by projecting these models to paleoclimate conditions (6ka and 21ka).

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Impact of sublimation on mass balance and geochemistry of high latitude ice sheets

People involved: Summer Rupper (Brigham Young University, UT, USA) and Lora Koenig (NASA Goddard, USA)

Contact: Summer Rupper

Aim

Test the sensitivity of sublimation to changes in climate. With this information, bound possible sublimation-induced changes in mass balance and ice core geochemistry to changes in boundary conditions. Not to be used as an exact magnitude of change test - just a sensitivity test to changes in climate.

Methods

Use a combination of measured sublimation rates and modern climate data (AWS, Reanalysis, etc) to test the sensitivity of ice sheet sublimation to interannual variability in climate. Use the PMIP suite of paleoclimate runs to test changes in sublimation rates under large changes in boundary conditions. The combination of modern and paleo modeling intercomparisons will be used to bound the possible impacts of sublimation on ice sheet mass balance and geochemistry of stable water isotopes in ice cores.

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Ecological niche modelling of plant species in the Albany Thicket, South Africa

People involved: Alastair Potts, Terry Hedderson (University of Cape Town, South Africa) and Richard Cowling (Nelson Mandela Metropolitan University, South Africa)

Contact: Alastair Potts

Aim

The aim of this study is to determine the extent of suitable habitats across valleys and mountain ranges for six lowland plants species from the Albany Thicket Biome found within South Africa in the present and during the Last Glacial Maximum. We will test whether:

• the distributions of these plant species were larger and more cohesive than the current patchy and isolated populations,
• suitable habitat has shifted eastwards between the LGM and present due to the shifting winter-rainfall regime
• the distributional response varies among the selected plant species.

Methods

The methods will follow those used by Waltari and Guralnick (2008) J. Biogeogr., where they examined the past and present distributions of montane mammals using ecological niche modelling techniques coupled with data produced by the WORLDCLIM and MIROC models.

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Development of paleoclimatic bioclimatic GIS datasets for ecological niche modeling applications

People involved: A. Townsend Peterson, Jorge Soberon, Narayani Barve (University of Kansas Biodiversity Research Center, Lawrence, Kansas, USA), Jesús Muñoz (Real Jardín Botánico, Madrid, Spain) and Volker Bahn (Wright State University, Dayton, OH , USA)

Contact: A. Townsend Peterson

Aim

To develop sets of bioclimatic raster GIS datasets summarizing paleoclimate outputs of PMIP2-participating climate modeling centers for use in ecological niche modeling and Pleistocene biogeography applications. At present, only CCSM and one MIROC models are in use in Pleistocene biogeography applications, which offers rather a limited view into the much-broader data resources that PMIP2 has created. We aim to downscale and process into bioclimatic dimensions all of the PMIP2 model outputs for mid-Holocene and Last Glacial Maximum, to produce a much more in-depth view of Pleistocene-Holocene climates for the niche modeling and biogeography community.

Methods

We have discussed the details of methods for downscaling climate model outputs at length with colleagues at NCAR (Caspar Amman and others), as well as with colleagues in the niche-modeling world (Robert Hijmans and others), and have considerable GIS and programming ability represented within our group. We plan to create suites of bioclimatic variables that will be of maximum utility to specialists in biodiversity modeling and biogeography, as they summarize climate features that are particularly relevant to constraining species' geographic distributions. Our anticipated protocol is as follows:

1. Download and collate all PMIP2 model outputs.
2. Import from native data formats into raster GIS grid formats.
3. Collate with present-day data sets ((http://www.worldclim.org/)) at 10' resolution, and subtract to produce a difference map for each month for precipitation and temperature.
4. Smooth the difference map using splining techniques to produce a difference map with 10' resolution.
5. Add the smoothed difference map to the present-day data set to produce month-specific temperature and precipitation layers for past time periods.
6. Process the month-specific temperature and precipitation layers into bioclimatic layers using scripts provided on the WorldClim page (script at http://www.worldclim.org/mkBCvars.amll).

Secondary data products will be made as widely available to others in the niche modeling and biogeography community as PMIP2 permissions permit.

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LGM wetland distribution and methane emissions

People involved: Nanne Weber and Michiel van Weele (KNMI, NL)

Contact: Nanne Weber

Aim

It is an open question to what extent wetlands contributed to the interglacial-glacial decrease in atmospheric methane concentration which is derived from ice-core data. In this project we will estimate methane emissions from glacial and pre-industrial natural wetlands, using the latest paleoclimate scenarios from PMIP2 simulations. The aim is to analyse the relative role of different factors (temperature, vegetation, hydrological cycle) in the glacial decline.

Methods

Wetland distribution and methane emissions for the LGM and PIH will be computed off-line from the dominant climatic and vegetation controls, using PMIP2 model output. We will use a wetland location algorithm and relations for wetland emissions as commonly used in state-of-the-art process-based models.

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LGM warm pool data-model comparison

People involved: Aradhna Tripati

Contact: Aradhna Tripati

Aim

To compare new proxy estimates of LGM sea surface temperatures in the West Pacific Warm Pool based on clumped isotope thermometry to reconstructions from other proxies and simulated values from the PMIP-2 models.

Methods

I plan to:

1. Compare estimates of temperature from clumped isotopes to published Mg/Ca, alkenone, and transfer function temperatures, in order to assess if there is a systematic bias in some of these proxies.
2. Analyze sea surface temperatures predicted by the PMIP-2 models for the LGM for 15° N-15° S in the West Pacific Ocean
3. Compare simulated ocean temperatures for the surface with proxy estimates from clumped isotope thermometry to assess if there is a systematic bias in some of these models.

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The equatorial thermocline and tropical climate change

People involved: Pedro DiNezio and Amy Clement (University of Miami, Florida, USA)

Contact: Pedro DiNezio

Aim

Explore the role of the equatorial thermocline in the climate response of the equatorial Pacific to LGM boundary conditions.

Methods

Estimate a heat budget of the surface layer and identify the processes involving the thermocline that are robust across models.

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Proxy versus model-proxy comparison: Holocene climate evolution of the North Atlantic ocean

People involved: Bernd Rombaut (Ghent University, Ghent, Belgium)

Contact: Bernd Rombaut

Aim

Methods

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Behaviour of the dynamic warm pool during the LGM and Mid-Holocene

People involved: Carlos Hoyos, Paula A. Agudelo, Peter J. Webster (Georgia Institute of Technology, Atlanta, GA, USA)

Contact: Carlos Hoyos

Aim

The region of atmospheric heating in the tropics, here termed the dynamic warm pool, represents the boiler box of the planetary heat engine and plays a determining role in global climate and tropical weather variability, modulating the genesis and intensification of tropical cyclones, the ascending branches of the Walker and Hadley circulations, monsoons and ENSO variability, and the nature of global teleconnections emanating from the tropics. Hence, it is important to understand how the tropical warm pool has changed in the past and how it may change in the future, and how these changes may alter climate both regionally and globally. The concept of the dynamic warm pool, which encloses the region of net atmospheric convective heating in the tropics, is fundamentally different to the traditionally defined oceanic warm pool corresponding to the area occupied by sea surface temperatures above a pre-defined threshold, typically 28°C. While the traditionally defined warm pool has expanded as a result of global warming, the dynamical warm pool has remained constant as a result of an increasing column integrated heating-sea surface temperature threshold.

Methods

In light of these results, the traditional warm pool definition and the thresholds for convection and cyclogenesis are not climatically meaningful and lack a physical basis. Rather than a static definition set by a constant temperature, the climatically active warm pool should be defined dynamically by the large-scale coupled ocean-atmosphere system rather than just by the temperature of the ocean surface. In this work we use the concept of the dynamic warm pool as a physical basis to explore and understand long-term variability of tropical climate and its influence in global atmospheric circulation and teleconnections, and monsoon variability. In orther to study the dynamic warm pool in past climates we plan to estimate Column Integrated Heating (CIH) from PMIP2 model and study the relationship between SST and CIH during the LGM and Mid-Holocene. We also plan to study changes in the P-E distribution in past climates compare to the present.

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LOOP Current variability - its relation to meridional overturning circulation and the impact of Mississippi discharge

People involved: Carsten Eden, Dirk Nürnberg, Tanja Mildner (IFM-GEOMAR, Kiel, Germany)

Contact: Tanja Mildner

Aim

The focus within the LOOP project lies on two major topics. The first is the impact of the LOOP Current extent and variability on the Gulf of Mexicos' (GOM) surface hydrography and its changes during Cold-deglacials, Warm-deglacials and Interglacials. The second major issue is to investigate the LOOP Current, its relation to the meridional overturning circulation (MOC) and the impact of the Mississippi river discharge.

Methods

For a first approach the idea with the numerical and theoretical part is to set up several sensitivity experiments to yield some first qualitative ideas of the circulation changes during the periods of interest. These experiments can be split uo into simulations of the ocean in response to

1. decreased sea level
2. changes in the surface forcing (wind stress) over the North Atlantic
3. Mississippi point-source freshwater influx at different rates

We use a present day regional eddy-resolving model of the North Atlantic (Family of Linked Atlantic Model Experiments: FLAME) with 3 different model resolutions, namely 4/3°, 1/3° and 1/12°. In particular the aim is to focus on the higher resolution of 1/3° and 1/12°, as those scales reveal meso-scale processes such as eddies.

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Geographic variation in subspecific diversification of birds

People involved: Paul R. Martin, William Nelson (Queen's University, Kingston, ON, Canada) and Joshua J. Tewksbury (University of Washington, WA, USA)

Contact: Paul R. Martin

Aim

To test predictions of alternative hypotheses to explain geographic variation in subspecific diversification of birds in the Americas. Subspecies are groups of phenotypically-distinct populations that have not yet evolved reproductive isolation characteristic of biological species.

Understanding the causes of geographic variation in subspecific diversification may provide insight into the factors influencing the early stages of speciation.

Methods

We mapped the geographic distribution of subspecies for 1153 species of birds in the families Trochilidae and Fringillidae and calculated mean density of subspecies per species for a grid of points across the Americas. Using these data as a dependent variable, we will test predictions of alternative hypotheses to explain geographic variation in the mean densities of subspecies. One hypothesis to explain variation in subspecies density concerns recent changes in climate over the last 21,000 years, which is why we are requesting data from PMIP2.

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The Arctic ocean during the Last Glacial Maximum

People involved: Kristofer Döös and Maxime Ballarotta (Stockholm University, Sweden)

Contact: Maxime Ballarotta

Aim

Understand the Arctic ocean state during the Last Glacial Maximum, validate LGM scenarios.

Methods

The ocean system NEMO will be used and forced by LGM atmospheric fields. Different ORCA resolutions will be tested.

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Comparative automated validation of a higher-order Ice Sheet Model driven by PMIP2 derived boundary conditions with high-resolution GIS of the glacial-geomorphological record

People involved: Alun Hubbard, Henry Patton (Aberystwyth University, Ceredigion, UK), Tom Bradwell, Nick Golledge (British Geological Survey, UK), Sarah Greenwood, Krister Jansson, Nina Kirchner, Johan Kleman, Arjen Stroeven (Stockholm University, Sweden), Mike Kaplan (Lamont-Doherty Earth Observatory, USA), Yingkui Li (University of Missouri, Columbia, MO, USA), and Jakob Napieralski (University of Michigan, Dearborn, MI, USA)

Contact: Alun Hubbard

Aim

To utilise PMIP2 data to test, guide and modify constraints on a suite of coupled high-resolution surface energy balance/ice flow models to investigate and optimise the palaeo-ice footprint and its associated dynamics using new databases of glacial-geological reconstructions across New Zealand, Patagonia, western North America, Iceland, Fennoscandia/Barents Sea and the UK and Ireland.

Methods

Recently developed automated methods for assessing and optimising the time-transgressive ISM footprint [ice extent (APCA) and basal flow regime and direction (AFDA)] enables the optimisation of ensemble forward experiments against high resolution data of Quaternary geomorphology and glacial geology contained in Geographical Information Systems (Napieralski et al., 2007; Golledge et al., 2008; in press., Hubbard et al., in press). This loose inverse procedure enables the broad definition of palaeo-climatic envelopes which are relatively independent of the data used to constrain the PMIP2 experiments and the Ice-5G reconstruction which informed them.

We wish to use PMIP2 data in combination with other proxies to define potential palaeo-climatic configurations for determining the surface mass balance condition at key time-slices over the last glacial cycle into the early Holocene. These palaeo-climatic snap-shots will be modified using manual and control perturbation methods to optimise output from ensemble experiments against the offshore sedimentary chronology, maximal and deglaciation reconstructions and new ice flow lineations contained in a GIS. The project will yield improved insight and linkages into ice sheet dynamics, feedbacks and non-linear responses to climate and their resulting glacial geological and geomorphological signatures.

• Golledge, N. R., Hubbard, A., and Sugden, D. E. (2008) High-resolution numerical simulation of Younger Dryas glaciation in Scotland. Quaternary Science Reviews, 27, 888-904.
• Golledge, N. R., Hubbard, A., and Sugden, D. E. (2009) Mass balance, flow, and subglacial processes of a modelled Younger Dryas ice cap in Scotland. Journal of Glaciology, 55.
• Hubbard, A., Bradwell, T., Golledge, N., Hall, A., Patton, H., Sugden, D., Cooper, R. & Stoker, M. in press. Dynamic cycles, ice streams and their impact on the extent, chronology and deglaciation of the British-Irish Ice Sheet. Quaternary Science Reviews.
• Napieralski, J., Hubbard., A., Li, Y., Harbor, J., Stroeven, A., Kleman, J., Alm, G. & Jansson, K. 2007. GIS enhanced analysis of ice sheet model output using geomorphic data. Journal of Glaciology, 53, 180.

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Interactions between climate and marine biogeochemical cycles in past climates

People involved: Birgit Schneider (University of Kiel, Germany)

Contact: Birgit Schneider

Aim

To study the links between climate and marine biogeochemical cycles during climates of the past, which may:

1. give important insight into the interpretation of paleo proxies that are based on marine organisms such as phytoplankton and zooplankton
2. help to resolve model-model, model-proxy and proxy-proxy discrepancies

Methods

Climate model ensembles will be used to assess the robustness of simulated past climate trends. The application of a marine biogeochemical model (PISCES) that includes four plankon functional types (2x phytoplankton, 2x zooplankton) will be used to investigate a potential impact of shifts in the climate system (e.g. seasonality) on plankton populations, which may carry their signal into ocean sediments.

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Comparison of SST reconstructions over the past 500kyr with results from the PMIP2 model simulations

People involved: Carolyn Snyder (Stanford University, USA)

Contact: Carolyn Snyder

Aim

This project provides a comparison to ongoing work analyzing the spatial and temporal patterns of sea surface temperature (SST) change over the past million years from SST proxy records (currently 54 SST records over 100kyr long). The goal is to compare the latitudinal gradients of SST response obtained from the proxy records analyzed over the last 500kyr with those predicted from the PMIP2 model simulations.

Methods

We plan to:

1. Estimate the zonal average deviations (by latitude) for the PMIP2 simulations.
2. Compare those latitudinal gradients with ones obtained from proxy records analyzed continuously over the last 500kyr.
3. Compare local SST response to global climate changes from the proxy records (estimated over the last 500kyr) and from the PMIP2 simulations (estimated at a single time point compared to present).

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Moisture transport from the Atlantic to the Pacific basin and its response to North Atlantic cooling

People involved: Ingo Richter and Shang-Ping Xie (University of Hawaii at Manoa, Honolulu, HI, USA)

Contact: Ingo Richter

Aim

Atmospheric moisture transport from the Atlantic to the Pacific basin plays an important role in regulating North Atlantic salinity and thus the strength of the thermohaline circulation. Changes in the strength of this moisture transport can thus have an important influence on the stability of the thermohaline circulation. During past events of North Atlantic fresh water pulses the collapse of the thermohaline circulation led to intense cooling that extended to the tropical North Atlantic. Our goal is to examine how such cooling events might influence the atmospheric moisture export from the Atlantic basin and thus feed back on the thermohaline circulation. To this end, we would like calculate moisture transport in the PMIP2 water hosing experiments. The results will be compared with those from a high-resolution regional model that realistically simulates the Central American gap winds, which are important to the inter-basin moisture transport.

Methods

We would like to calculate moisture transport in the PMIP2 water hosing experiments. To this end we need 3D fields of zonal and meridional velocity, and specific humidity. Monthly data will be sufficient for our purposes since transients play only a minor role in the tropical regions we are interested in. Daily means, however, would be preferable.

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Trace gas variability during the Last Glacial Maximum

People involved: Allegra LeGrande, Apostolos Voulgarakis, Olga Pechony, Greg Faluvegi, Drew Shindell, Nadine Unger (Columbia University, New York, NY, USA)

Contact: Allegra LeGrande

Aim

The initial goal of this experiment is to examine the sources and sinks of atmospheric methane during the Last Glacial Maximum. Wildfire emissions can impact both the sources and the sinks of methane in the atmosphere.

Methods

We are interested in variables related to vegetation changes during the Last-Glacial Maximum (LGM), including Leaf-Area-Index, vegetation density, vegetation type, etc...

We are planning to use these variables, in order to drive the wildfire scheme of the NASA Goddard Institute for Space Studies (GISS) climate model for LGM conditions.

In the future, a series of other experiments related to the LGM will possibly be conducted, and the wildfire scheme will, in many cases, be of central importance.

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Effects of past and future climate change on Victorian temperate rainforest fauna

People involved: Verity Miles, Adnan Moussalli and Devi Stuart-Fox (University of Melbourne, Australia)

Contact: Verity Miles

Aim

Our aim is to map out the past, current and future distributions of cool temperate rainforests in south-eastern Australia using land snails from the genus Victophanta as a study species. We aim to test the accuracy of at least 5 different climate simulations run in both past and future scenarios. Verification of accuracy of past simulations will be done using fossil pollen records and molecular data.

Methods

Species distribution models (SDMs) will be constructed using field surveys and museum records. Climate layers will be derived using ANUCLIM 5.1. SDMs will be constructed for past, present and future scenarios using various modelling techniques (MAXENT, BIOCLIM and GLMs). Changes in distributions between the present and past or future will be determined.

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Palaeo-distribution of Australian fauna: using knowledge of the past to inform the future

People involved: Jeremy VanDerWal (James Cook University, Australia) and Linda Beaumont (Macquarie University, Australia)

Contact: Jeremy VanDerWal

Aim

To project models of current distributions of Australian fauna on past climates. These models will be used to examine past species refugia, validating phylogeography of species, and better informing accuracy of such models being projected into the future.

Methods

We propose to project species distribution models onto the different PMIP2 models, creating an ensemble model of where the species may have occurred in the past. This would help to identify areas of potential refugia for broad groups of species. We will then attempt to correlate such refugia with the phylogeography of species for which such information is known. This will be an expansion of work that has been done on a small rainforest region of Queensland where by past climates were based on a single pollen core. Such correlation of refugia and phylogenetics offers validity to projections of species distributions into the future.

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Investigation of the Ocean climate change during the Mid-Holocene and Last Glacial Maximum

People involved: Seong-joong Kim and Eun-jin Woo (Korea Polar Research Institute)

Contact: Eun-jin Woo

Aim

To investigate the ocean thermohaline properties and circulation during the Mid-Holocene and Last Glacial Maximum.

Methods

Data analysis.

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Relating deep ventilation of the ocean to its surface boundary conditions and investigate the implication for glacial CO2 hypotheses

People involved: Agatha de Boer (University of East Anglia, Norwich, UK)

Contact: Agatha de Boer

Aims

The deep ocean is ventilated by different fractions of North Atlantic, Southern Ocean and to a lesser extent, North Pacifc surface water. We would like to determine which aspects of the surface boundary conditions lead to the distribution of these properties in the deep ocean.

Also, we are interested in the extent to wind driven upwelling in the Southern Ocean affects the distribution of the deep water masses.

Methods

• Derive a quantitative method to distinguish between various water masses in the deep ocean.
• Apply the method to the various models for the glacial and the present day.
• Correlate specific water mass distributions and surface boundary conditions such as wind and buoyancy forces and investigate the reasons for the correspondence.
• Produce and use streamfunction plots to the extent that they can assist in the analysis of deep ventilated patterns (limited applicability in Southern Ocean).
• Assess which deep ventilation patterns are most likely to produce and maintain a drawdown of CO2 in the deep ocean.

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The effect of the atmospheric circulation on the surface mass balance of the LGM ice-sheets

People involved: Johan Liakka, Florence Colleoni, Johan Nilsson and Heiner Körnich (Department of Meteorology, Stockholm University, Sweden)

Contact: Johan Liakka

Aim

In the presence of a basic-state zonal wind, it is well-established that large topographic features, such as continental-scale ice-sheets, induce atmospheric temperature anomalies. In turn, these anomalies influence the surface mass balance of the ice-sheets that are forcing them, leading to a feedback mechanism. The aim of this project is to use PMIP2 data to quantify the importance of the atmospheric circulation on the accumulation and ablation rates of the Laurentide and Fennoscandian ice-sheet, and possibly highlighting the potential differences induced by each GCM.

Methods

1. Identify the patterns of the circulation-induced temperature anomalies (deviations from the zonal mean state) in each of the PMIP2 models.
2. Quantify the effect of these anomalies on the surface mass balance of the ice sheets.

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The effect of Holocene climate change on global duck genetics

People involved: Volker Bahn, Jeff Peters, Kendra Millam, Kevin McCracken and Patrick McAfee (Department of Biological Sciences, Wright State University, Dayton, OH, USA)

Contact: Volker Bahn

Aim

Our overarching goal is to explore how past climate and habitat change has influenced the spatial arrangement of genetic diversity around the globe. In particular, we plan to combine genetic data and palaeodistribution modeling to test models of population and demographic history for globally distributed ducks (Genus Anas). The combined dataset will be useful for:

1. generating testable, quantitative predictions from the projected climate change scenarios,
2. and validating the ability of distribution models for handling climate change.

Methods

We have genetic data (DNA sequences from seven or more independent loci per species) for 10 duck species sampled throughout the northern hemisphere and five South American species. In addition, we are adding comparable datasets for five African species and four Australian species to provide a global perspective on climate change. We will use current climate and duck distributions to create distribution models for these species and use the models to hindcast duck distributions at LGM. In addition to the palaeoclimate, we will predict the current and LGM distribution of wetlands as an important habitat for ducks to make the distribution models ecologically relevant. The duck distributions at LGM will inform us about population contractions, increases, shifts and separations, which we will then test using patterns of genetic diversity within and among populations.

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Representing the vegetation distribution and terrestrial carbon dynamics under the mid-Holocene, Last Glacial Maximum condition by the Spatially-Explicit Individual Based DGVM

People involved: Tomomichi Kato, Colin Prentice (QUEST, University of Bristol, UK) and Sandy Harrison (BRIDGE, University of Bristol, UK)

Contact: Tomomichi Kato

Aim

We plan to use the Spatially-Explicit Individual Based DGVM (Sato et al., 2007. Ecol Modelling) to represent vegetation distribution, forest structure and carbon dynamics under the Paleoclimate condition. The SEIB-DGVM can simulate individual trees' growth and their competition with neighboring trees on spatially explicit 30m x 30m stands, and extrapolate the outcomes from the representative stands over the entire DGVM grids. This approach allows examining the forest size- and age- structure among the co-existing PFTs, and dynamical changing of vegetation distribution by considering competition, settlement and mortality rate. We are aiming to clarify the differences in vegetation distribution, forest structure and carbon dynamics among the periods (0ka, 6ka and 21ka), and the effect of several key parameters on them.

Methods

Our study will be in three phases:

1. Validation: pollen data and other modeled data (BIOME4, etc.) will be used for evaluating the performance.
2. Vegetation distribution analysis: the differences in vegetation distribution, forest structures and carbon dynamics among the periods will be clarified, and their causes will be discussed.
3. Sensitivity analysis: altered value of several parameters, regarding competition, settlement rate, and mortality will be given to the model simulation for examining the importance of each parameter on the vegetation distribution and forest traits under the Paleo-environments.

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Paleo Arctic Ocean hydrograph and sea ice distribution at Last Glacial Maximum

People involved: Xun Gong and Gerrit Lohmann (Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany)

Contact: Xun Gong

Aim

To assess the realism of simulated Arctic Ocean and Nordic Sea surface circulation and sea ice transport through comparison of simulated model outputs and observed sediment cores at the LGM, and discuss the domain mechanism of glacial Arctic Ocean circulation.

Methods

We will:

1. Compare paleo Arctic Ocean and Nordic Sea surface circulations of regional NAOSIM model (North Atlantic & Arctic Ocean Sea Ice Model) with PMIP2 model simulation outputs.
2. By the advantage of NAOSIM model, regenerate forcing conditions, to make new runs and discuss the sea surface circulation and sea ice transports in northern hemisphere higher latitudes of LGM.
3. Validate the model simulations with the observed geological and biological evidents (eg. sediment cores, ice sheets evidence).

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Modelling ₁₃C in plants and soils

People involved: Philippe Ciais (LSCE, Gif-sur-Yvette, France) and Marko Scholze (University of Bristol, UK)

Contact: Marko Scholze

Aim

To apportion land and ocean C stocks during the LGM, ₁₃C can be used, but this requires better knowledge of the isotopic composition of the land biota. The proposed analysis is to use PMIP2 climate fields for driving one terrestrial carbon model (LPJ) run in Bristol university. The LPJ model has a unique isotopic capability and will be used to calculate the isotope composition of land biota. An uncertainty on this number will be derived from the range of climate simulations.

Methods

LPJ will be driven by (paleo)climate fields to calculate 13C of each biome as well as stock and fluxes for the LGM and PIH climate.

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Visualization of late Quaternary and Modern landscape dynamics

People involved: Jörg Bendix (Philipps University of Marburg, Germany) and Hermann Behling (University of Göttingen, Germany)

Contact: Jörg Bendix

Aim

The main aim is the visualization of late Quaternary and modern landscape dynamics (vegetation, biodiversity, climate, fire, land use) in the Podocarpus National Park and neighbouring regions in Ecuador (South America). The first step is the spatial reconstruction of landscape dynamics where the work will be conducted by means of pollen profile-, meteorological- and GIS-data (recent satellite-derived land cover and digital elevation model and derived topographical parameters etc.). Vegetation and anthropogenic fire dynamics is examined at several points for different time slices in the late Quaternary and Holocene optimum from pollen data. The current (potential) vegetation cover is reconstructed by vegetation surveys in the study area of southern Ecuador , already conducted in the collaborative DFG research unit 816 (www.TropicalMountainForest.org). With satellite data, climate information (interpolated measurements, NCEP-NCAR and WRF-simulated data) , the actual potential vegetation is reconstructed and visualized by rendering techniques. PMIP GCM results for the LGM and 6000 yr B.P. shall be downscaled to the project area and used to:

1. compare with the vegetation structure derived from pollen cores
2. reconstruct and visualize past landscape dynamics for both periods

Methods

We plan to:

1. Statistically downscale PMIP GCM data for air temperature and rainfall by using present-day interpolated meteorological fields and the climate analysis and empirical-statistical downscaling (ESD) package of Benestad et al. (2007).
2. Use the downscaled data fields of temperature and rainfall for 6ka and 21ka to compare it with the outcome of pollen vegetation analysis for different altitudinal levels in the Andes of Ecuador.
3. Render the landscape of southern Ecuador based on 6ka and 21ka vegetation and climate information using Terragen software.

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Integrating species distribution models, Geographic Information Systems and coalescent phylogenetic methods into phylogeography studies

People involved: Jason Brown (Duke University, Durham, NC, USA)

Contact: Jason Brown

Aim

To better understand the current and historic patterns of biodiversity.

Methods

Using the PMIP data, species distribution models, and phylogenetics, I will generate current and historic distribution models of focal species (primarily anurans) and use these models to better understand diversification patterns.

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Climate feedback analysis in LGM and global warming experiments

People involved: Christelle Castet, Sandrine Bony and Jean-Louis Dufresne (LMD, Paris, France)

Contact: Christelle Castet

Aim

The aim of the study is to address the question of spread of various feedback parameters in GCMs used in PMIP2.

Methods

The PMIP2 models' outputs will be used to calculate various climate feedbacks in the LGM using Soden (2008) radiative kernel method.
The feedback strengths in LGM will be studied and compared to the feedback strengths in global warming experiments.

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Characterization of a secondary contact zone of populations of the black-spotted frog in northeastern China

People involved: Kaiya Zhou, Yi Kong, Jie Yan, Jie Du, Ce Chen (Nanjing Normal University, China)

Contact: Yi Kong

Aim

We intend to study patterns of introgression between two clades; examine the gene flows between clade A and clade B, and reveal historical distribution scenario for the frog populations combining molecular data and paleoclimate factors in Quaternary.

Methods

1. Study the genetic structure of the populations in the secondary contact zone with discrete molecular markers.
2. Investigate impact of peleoclimate fluctuations on distribution patterns of Pelophylax nigromaculata since LGM, generating a paleodistribution model.
3. Test alternative biogeographical hypotheses.

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Climatic variability and the evolution of biodiversity

People involved: Roland Jansson, Larisa Harding and Genoveva Rodriguez-Castaneda (Umeå University, Umeå, Sweden)

Contact: Roland Jansson

Aim

The primary aim of this project is to understand how recurrent climatic fluctuations affect evolution and the global distribution of species. Specifically, we aim to test the importance of climatic variability for species diversification, and the degree of genetic divergence among gene pools within species.

Methods

We will use PMIP2 climate simulations to infer the degree of range dynamics experienced by taxa in different regions, and test to what degree this can explain rates of species diversification in lineages and the degree of genetic divergence within species. The climatic simulations will be sued both for creating indices of range dynamics experienced by taxa, and as input data in species distribution modelling.

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Downscaling tropical cyclone activity during the LGM

People involved: Kerry Emanuel (MIT, Cambridge, MA, USA)

Contact: Kerry Emanuel

Aim

To estimate tropical cyclone characteristics during the LGM. These included the frequency, intensity, and tracks of storms.

Methods

The method is a novel form of downscaling in which a specialized, coupled atmosphere-ocean tropical cyclone model is driven by global model fields to produce many (order 10^4) tropical cyclone events. This method has been published in two papers:

   hurr_risk.pdf
and
   Emanuel_etal_2008.pdf

The method successfully reproduces the major characteristics of global tropical cyclone activity when driven by NCAR/NCEP reanalysis fields, and has also been applied to 7 of the IPCC AR4 model simulations to downscale TC activity under scenario A1b. Alexey Federov at Yale and I have a paper into Nature describing the results of downscaling the climate of the Pliocene, driven by CAM3 model output using paleo reconstructions of Pliocene sea surface temperature.

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Land-Ocean asymmetry of tropical precipitation change in mid-holocene

People involved: Chia Chou and Chia-Wei Lan (Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan)

Contact: Chia-Wei Lan

Aim

We want to use complex model output to do this study and find the difference result between our simplified model and PMIP.

Methods

In the intermediate climate simulations, we found a clear land-sea contrast in precipitation change between mid-Holocence and current climate. We would like to examine this land-sea contrast in PMIP II simulations and study the robustness of this phenomenon. We would also like to examine possible ENSO events in mid-Holocence and compare these events to current ENSO.

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Theoretical scaling of the hydrological cycle in paleoclimates

People involved: William Boos (Harvard University, USA); Wally Broecker (Columbia University, USA)

Contact: William Boos

Aim

We will examine whether the theoretical scalings proposed by Held and Soden (2006) for the hydrological cycle hold in the Last Glacial Maximum (LGM) as simulated by PMIP2 climate models. We will also examine the degree to which shifts in the intertropical convergence zone caused by anomalous mid-Holocene insolation and LGM ice sheets can be predicted by the theory of Kang et al. (2008) that views these forcings as resulting from implied meridional heat transports which may be compensated for by atmospheric heat transports.

Methods

We will examine whether the theoretical scalings proposed by Held and Soden (2006) for the hydrological cycle hold in the Last Glacial Maximum (LGM) as simulated by PMIP2 climate models. We will also examine the degree to which shifts in the intertropical convergence zone caused by anomalous mid-Holocene insolation and LGM ice sheets can be predicted by the theory of Kang et al. (2008) that views these forcings as resulting from implied meridional heat transports which may be compensated for by atmospheric heat transports.

References:

• Held, I. M., and B. J. Soden, 2006: Robust responses of the hydrological cycle to global warming. J. Climate, 19, 5686-5699.
• Kang, S. M., I. M. Held, D. M. W. Frierson, and M. Zhao, 2008: The response of the ITCZ to extratropical thermal forcing: Idealized slab-ocean experiments with a GCM. J. Climate, 21, 3521-3532.

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Pleistocene refugia of European aquatic insects

People involved: Miklós Bálint (Babes-Bolyai University, Cluj, Romania), Sami Domisch, Carsten Nowak, Jan Sauer (Naturmuseum Senckenberg, Frankfurt, Germany) and Steffen Pauls (University of Minnesota, St Paul, MN, USA)

Contact: Miklós Bálint

Aim

Aquatic species are relatively poorly represented in biogeographical studies. The European mountains provide suitable habitats for a large number of aquatic insects. These species were able to survive Pleistocene glaciations in the vicinity of their present-day habitats, as running streams represent stable environments over broad time periods.

The first goal of our project is to evaluate the location of already proposed LGM extramediterranean refugia for nine aquatic insect species in Europe. The second aim is to validate their already proposed recolonization routes during the mid-Holocene.

Methods

The locations of suitable habitats of seven Trichoptera, a Plecoptera and an Ephemeroptera species during the Last Glacial Maximum and mid-Holocene will be estimated using ecological niche models. These locations will be compared to refugia and recolonization routes proposed in earlier publications (identified on a phylogeographic basis, using mtDNA sequences).

The approach makes possible the evaluation of niche conservatism of the target species. The combination of ecological niche modeling with phylogeography will likely contribute to a more precise understanding of the history of mountain aquatic organisms in Europe.

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Phylogeny of New World Zopherini: past climate and the role of fragmentation in speciation processes

People involved: Andrés Baselga, Mario García-París and Ernesto Recuero (Universidad de Santiago de Compostela, Santiago de Compostela, Spain)

Contact: Andrés Baselga

Aim

Our aim is to assess the effect of past climate change on speciation processes in two clades of New World Zopherini that present very different patterns of phylogenetic branching. We want to test whether different climatic requirements could lead to different contractions/expansions of distributions under climate change, and the influence of these range oscillations on speciation processes.

Methods

Using distribution models we would estimate the distribution of clades under present and past climates. This would allow to assess the effect of past climate changes on clade distributions (i.e. fragmentation), and how this change could be related to isolation of populations leading to speciation processes.

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Environmental sorting of vertebrate faunas: Is guild-level locomotor and dietary ecomorphology an indicator of paleoenvironment?

People involved: P. David Polly, A. Michelle Lawing (Indiana University, Bloomington, IN, USA), Jason J. Head (University of Toronto, Canada) and Jussi Eronen (Helsinki University, Finland)

Contact: P. David Polly

Aim

The project is looking at how ecometric measurements of locomotor morphology in mammalian carnivores and snakes (the two dominant guilds of terrestrial carnivore) are related to climate and environment.

Methods

We are collecting data on all North American species of both groups, including Late Pleistocene species. We have divided the continent into 50 km grid cells and are tabulating the carnivoran and snake faunas for each grid cell from digital range data (some of which will be produced by this project). Mean values for each 50 km fauna will be calculated for the locomotor and dietary indices and the results analyzed with GIS to determine association with climatic and environmental parameters (temperature, precipitation, elevation, vegetation cover, ecological province, and species richness). Mean digitigrady in carnivorans is the central focus -- several comparisons between its association with environmental factors will be made: it will be compared to substrate use in snakes to determine whether results are taxon specific; it will be compared to mean dietary morphology in carnivorans to determine whether all morphological systems in the same taxon have the same association with climate; and it will be compared to Late Pleistocene carnivoran locomotion to determine whether its association with environmental factors is constant in the face of climatic change.

We are interested in using the PMIP2 database as an independent source of climate and environment for the LGM against which to test our predictions based on ecomorphology. We will also use the PMIP2 data in GIS format to project species ranges and ecometric ranges into the LGM to derive models of species and morphological distributions and model how they were reorganized in the period since then.

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Paleodistribution models for eastern North American trees

People involved: Ashley B. Morris (University of South Alabama, Mobile, AL, USA)

Contact: Ashley B. Morris

Aim

Compare ecological niche models of paleodistributions of ENA temperate trees with phylogeographic patterns.

Methods

Ecological niche modeling will be performed on ENA tree species that share an eastern Mexican disjunction. Models will be developed for both current and paleodistributions, using variables from the PMIP2 data set. Observed patterns will then be compared to phylogeographic data to elucidate biogeographic patterns.

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Latitudinal variability of LGM climate and glaciation in the US Rocky Mountains - a field data vs. climate model comparison

People involved: Eric Leonard (Colorado College, Colorado Springs, USA), Ben Laabs (State University of New York, Geneseo, USA) and Mitchell Plummer (Idaho National Laboratory, Idaho Falls, USA)

Contact: Eric Leonard

Aim

Most climate models have suggested that LGM moisture regime in the western United States differed significantly from that of the present, with a general reduction of precipitation at the LGM in the northwestern US and northern Rocky Mountains and an enhancement of LGM precipitation in the southwestern US and southern Rocky Mountains. Recent chronological work (Liccardi and Pierce, 2008; Thackray, 2008) suggests that the local LGM may have been delayed by several thousand years in the northern Rockies compared to its timing elsewhere in the Rocky Mountains, a delay which may reflect aridity in the northern Rockies at the time of the global LGM (ca 21ka).

This project is aimed at assessing the modeled LGM latitudinal climate gradients in the US Rockies by comparing climate change necessary to sustain a series of well-mapped LGM glaciers along the crest of the Rockies from New Mexico on the south to Montana on the north, with climate model results. We will use a 2-d mass/energy balance and flow model to assess the climate necessary to sustain the individual mapped LGM glaciers, and compare these results to model results synthesized in PMIP2. The objectives of this project are part of a broader research goal to improve the understanding of the extent, chronology, and climate of the last glaciation in the US Rocky Mountains. Preliminary results of the project can be interpreted more effectively with access to PMIP2 data and will be the basis for a larger-scale research proposal to be submitted to the US National Science Foundation in January 2010.

Methods

The project involves three primary components:

1. The proposed analysis requires accurate maps of a suite of LGM alpine glaciers along a latitudinal transect from south-central New Mexico to northern Montana. Some of the necessary maps are available from previous studies. We are currently involved in field mapping projects that will provide the additional necessary maps.
2. To estimate the LGM climatic conditions at each mapped paleoglacier, we will use the 2-d mass/energy balance and flow model of Plummer and Phillips (2003). With this model we can account for the effects of both temperature and precipitation on glacier mass balance and extent and assess the effects of other factors, such as surface albedo, wind, cloudiness, or seasonality changes. Using modern instrumental climate data as a basis for simulating modern glacier and permanent snowfield distribution, we will calculate, for each paleoglacier, the combinations of temperature, precipitation, and seasonality changes from modern conditions that could have sustained the glacier at its LGM extent.
3. We will compare these individual glacier model results with PMIP2 model predictions of regional patterns of LGM temperature, precipitation, and seasonality changes to assess the extent to which PMIP2 regional results are consistent with paleoclimatic inferences made on the basis of local glacier extent. In this testing, we will likely also drive model simulations of individual glaciers with regional PMIP2 output.

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Pleistocene refugia, phylogeography, and ecological divergence of the eastern newt

People involved: Mizuki Takahashi (Bucknell University, Lewisburg, PA, USA) and Jon Eastman (Washington State University, Pullman, WA, USA)

Contact: Mizuki Takahashi

Aim

To test whether Pleistocene refugial retreat has affected intraspecific ecological divergence of the eastern newt, Notophthalmus viridescens. Four subspecies are currently recognized within N. viridescens. These subspecies genetically differ in expression of life history traits. By using phylogeographic and niche modeling approaches, we want to understand how adaptive radiation within N. viridescens has arisen.

Methods

We have estimated lineage histories and locations of Pleistocene refugia of N. viridescens by using molecular phylogenetic analyses. By using the data from PMIP 2, we would like to apply ecological niche modeling projected on climate conditions during the LGM to test whether the estimated Pleistocene refugia differ in ecological conditions. We hypothesized that use of multiple Pleistocene refugia promoted intraspecific ecological divergence of N. viridescens. Alternatively, adaptive radiation could also occur during postglacial habitat expansion.

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Testing phylogeographical scenario using Ecological Niche modelling in Leiopelma hochstetteri

People involved: Antoine Fouquet (Universidade de São Paulo, Brazil), Francesco Ficetola (University of Milano, Italy), Frank Drost, Dianne Gleeson (Landcare Research, Auckland, New Zealand) and Neil Gemmell (University of Otago, Dunedin, New Zealand)

Contact: Antoine Fouquet

Aim

Combined mtDNA and nuDNA phylogeography of Leiopelma hochstetteri, an endangered New Zealand endemic species, has revealed new conservation priorities and provided insights into evolutionary scenario for the species during Quaternary (Fouquet et al., 2009). Moreover, ENM has been developed for current, prehuman (-1300) and future climate which demonstrated the predictive power of the method with this species and also raised conservation and evolutionary issues (Fouquet et al., in prep). We intend to use ENM to provide an explicit test of the phylogeographic pattern by projecting environmental suitability during LGM and LIG.

Methods

Breaks in the distribution of environmental suitability during LGM and LIG will be compared to observed genetic breaks and their dates of origination. We will test how populations in unsuitable areas have survived in situ (as suggested by molecular datation) or are derived from adjacent populations (as suggested by the putative 38°S limit for the forest during LGM) and if LGM conditions could have fragment the range of the species enough to lead to such striking phylogeographic pattern? This will also give insight into the origin of subfossil remains in the South Island.

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Origin and spread of stock-keeping (OSSK)

People involved: James Conolly (Trent University, Peterborough, ON, Canada), Stephen Shennan, Keith Dobney, Sue Colledge and Barbara Stopp

Contact: James Conolly

Aim

We are carrying out a systematic survey of published/archived archaeological animal bone data in order to re-examine the evidence for the origins of stock-keeping in the Near East and its spread into Europe during the Epipalaeolithic and Neolithic periods, c.12,000 to 6,000 years ago.

Methods

The basis for our study is a comprehensive database of selected animal bone data from relevant sites in Southwest Asia and Europe. Analysis of these collated datasets will enable us to (a) establish the key characteristics of early Neolithic animal exploitation economies through time and over broad and geographic regions (b) understand the key factors that account for variation in early Neolithic animal exploitation; (c) explore possible variations in husbandry and hunting strategies that developed as Neolithic herding economies spread from their area/s of origin; (d) assess the speed of spread of livestock farming across Europe; (e) identify adaptive changes in husbandry and hunting practices; (f) investigate the evidence for local indigenous domestication.

Our methods involve the collection of published reports on zooarchaeological remains from archaeological sites in the study region, followed by statistical and spatial modelling of exploitation patterns. An important component of this is the assessment of the degree of co-variance between the representation of certain species and regional variation in ecology across the study area.

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Past range dynamics of trees in the Iberian Peninsula

People involved: Francisco Rodríguez-Sánchez, Juan Arroyo (University of Sevilla, Spain), Arndt Hampe and Pedro Jordano (Estación Biológica de Doñana-CSIC, Sevilla, Spain)

Contact: Francisco Rodríguez-Sánchez

Aim

To interpret phylogeographical patterns and predicted refugia of Iberian trees in the light of palaeoclimatic reconstructions.

Methods

We will do a systematic review of phylogeographical and palaeodistribution modelling studies dealing with tree species from the Iberian Peninsula, and will contrast their patterns to downscaled palaeoclimatic reconstructions for the LGM and mid-Holocene.

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Origins of maize: introgression from teosinte

People involved: Joost van Heerwaarden, Matthew Hufford and Jeffrey Ross-Ibarra (University of California, Davis, CA, USA)

Contact: Jeffrey Ross-Ibarra

Aim

We will use niche modeling to estimate past distributions of the wild ancestor of maize, teosinte, and incorporate information about past distribution into population genetic models of introgression and center of origin of maize.

Methods

We are currently analyzing a large marker dataset from >2000 plants, both wild and domesticated, sampled from across the range of maize in the Americas. We will use patterns of population structure to infer introgression from teosinte, and compare a number of models of introgression and origin and spread of maize using coalescent-based population genetic approaches.

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Local adaptation and genetic structure of Joshua Tree, Yucca brevifolia

People involved: Laura Vann and Jeffrey Ross-Ibarra (University of California, Davis, CA, USA)

Contact: Jeffrey Ross-Ibarra

Aim

We are investigating the population genetics of Joshua Trees as part of a project to investigate local adaptation, genetic structure, and the effects of climate change on Joshua Tree evolution. We hope to also get access to and sample DNA from preserved Yucca samples from pack-rat middens from several sites in the Southwest to compare to extant populations. We have already sampled 8 populations of Joshua Tree from across the species range, and genetic characterization of these populations is currently underway.

Methods

We will compare current population genetic structure to past distribution information to evaluate the role of gene flow and habitat fragmentation on current diversity in Y. brevifolia and, ideally, compare genetic differentiation of ancient samples to predictions based on past distribution.

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Modelling the growth and decay of Vestfonna glacier, Svalbard, during the last full glacial cycle

People involved: Kati Laakso (University of Helsinki, Finland)

Contact: Kati Laakso

Aim

The plan is to study the extent and dynamics of Vestfonna glacier, Svalbard, as a function of time. Timescale used in simulations is 100 ka.

Methods

Shallow-ice approximation code Sicopolis and multiphysics software package Elmer will be used in simulations. Present-day temperatures and precipitation values are interpolated and extrapolated by using the glaciation index which scales the GRIP δ¹⁸O record. The CCSM data access is requested in order to give LGM (Last Glacial Maximum) data as an input for the model.

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The impacts of climate change on Arctic/Alpine bird species

People involved: Barbara Anderson, Chris Thomas and Sarah Smith (University of York, UK)

Contact: Sarah Smith

Aim

To assess the ability of bioclimate envelope models to forecast climatically suitable areas for Alpine / Arctic bird species under different climate scenarios.

Methods

Using models developed based on current species distributions and climate data for Europe, we will hindcast the areas which would have been climatically suitable for a number of Alpine/Arctic species at the last glacial maximum. We will then compare these forecasts with the fossil record for this period.

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Integrating genetic, physiological, and spatial data to uncover patterns of population diversification in a montane salamander

People involved: Amy Luxbacher (University of Minnesota St. Paul, MN, USA)

Contact: Amy Luxbacher

Aim

I will investigate the extent to which past climatic suitability explains contemporary patterns of geographic genetic structure in a montane salamander that is endemic to the Great Smoky Mountains in eastern North America.

Methods

I will model the species' potential geographic distribution at the LGM and mid-Holocene by projecting ecological and mechanistic niche models onto climate data derived from GCM simulations of 21 and six thousand years before present. I will use outputs from these models to generate alternative hypotheses describing the species' potential past distributions. I will then apply a model-based phylogeography approach to evaluate support for the alternative historical hypotheses given contemporary data from multiple genetic loci.

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Testing the validity of a novel statistical-dynamical atmosphere model

People involved: Dim Coumou and Vladimir Petukhov (PIK, Potsdam, Germany)

Contact: Dim Coumou

Aim

The aim of this project is to test the behavior of our novel statistical-dynamical (SD) atmosphere model under LGM conditions and to compare it against existing GCM results.

Methods

Our new SD model accurately captures the 3D structure and seasonality of storm tracks in present day and 2xCO2 climates. As an additional benchmark test, we want to see how well it performs for substantially colder climates like the Last Glacial Maximum. To do this we will apply a 2-6days bandpass filter to existing PMIP2 GCM data in order to extract the synoptic scale kinetic energy and momentum fluxes as well as heat and moisture fluxes. This will be used to verify our SD model which will directly calculate these quantities under LGM forcings.

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Phylogeography of Vitellaria paradoxa and involvement of glacial refugia

People involved: François Allal, Zenor Logossa, Letizia Camus-Kulandaivelu, Alexandre Vaillant and Jean-Marc Bouvet (CIRAD, Montpellier, France)

Contact: François Allal

Aim

This project's objective is to understand phylogenetic patterns of Vitellaria paradoxa at two different scales, one limited around the actual Dahomey-gap and another including the whole natural distribution range (from Senegal to Uganda). Those studies try to connect actual genetic patterns with geographical barrier and ancient climate changes events, in order to verify glacial refugia hypothesis.

Methods

After molecular characterization of the species through its natural range, using chloroplastic and nuclear SSR markers and SNP, we will compare genetic diversity index in the different populations studied and the actual distribution to infer last glacial potential refugia, using the PMIP2 database.

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Genetic and phylogeographic structure in seven Mesoamerican oak species (Fagaceae: Quercus)

People involved: Hernando Alonso Rodríguez Correa, Antonio González Rodríguez and Ken Oyama N. (Universidad Nacional Autónoma de México, Mexico)

Contact: Hernando Alonso Rodríguez Correa

Aim

Our main objective is to reconstruct the genetic and phylogeographic structure of seven oak species along Mesoamerica and compare it with the ancestral distributions modeled to the LGM, in order to understand the dynamic in the migration processes that took place in the Mesoamerican oaks.

Methods

We will use molecular markers (SSR) and cpDNA to reconstruct the phylogeographic and genetic structure in the seven oak species. Then, we will compare the haplotypes founded with the areas suggested in the paleoclimate reconstructions as ancestral distribution zones and finally we will discus this information in an oak migration scenario.

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Modelling potential impacts of climate change on the bioclimatic envelope of the maned wolf (Chrysocyon brachyurus)

People involved: Ricardo Torres and Pablo Jayat (Universidad Nacional de Tucumán, Argentina)

Contact: Ricardo Torres

Aim

This project aims to identify the potential changes in the future distribution of the maned wolf (Chrysocyon brachyurus), the largest living South American canid, under different climate change scenarios, so these changes can be taken into account in conservation management. For this we elaborate the following objectives:

1. determine the set of environmental characteristic than best explain the actual distribution for the species
2. model the actual distribution for the species based on these environmental characteristics
3. model the climatic envelope of the species for past conditions
4. model the future distribution for the species based on the different expected scenarios of climatic change and compare it with those obtained for past and present

Methods

Based in occurrence records obtained from museum collections, localities cited in the bibliography, and personal observations, the current climatic envelope of maned wolf will be modeled taking in account the 19 bioclimatic variables obtained from the WorldClim database. Niche modeling will be performed using Maxent v3.0. Niche model will be projected to two PMIP2 climate models of past conditions, mid-Holocene (wettest than current conditions in study area) and pre-industrial (driest than current conditions). The predicted distributions for the mid-Holocene conditions will be contrasted with information available from the fossil record which suggests a more southern distribution during that time compared with the current distribution. Finally, projections to future conditions under the CCCMA (A2 and B2) and HADCM3 (A2 and B2) scenarios obtained from the WorldClim database will be performed.

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African paleotemperature

People involved: James Russell and Tom Johnson (Brown University, Providence, RI, USA)

Contact: James Russell

Aim

We propose a comparison of changes in African temperatures at 21 and 6 kyr BP recorded in new organic geochemical proxy datasets against PMIP2 simulations. Our analysis will focus on comparing temperature changes at these times at both the regional (grid cell) and continental scale.

Methods

Simple model-paleoproxy comparisons:

• Analyze annual surface air temperatures predicted by the PMIP2 models at the grid cells for which we have paleotemperature data, as well as regional and continental averages
• Comparison of these simulations to proxy estimates
• Analyze the seasonal cycle of temperature in the simulations to help assess proxy reconstructions

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Pleistocene refugia and phylogeographic hypothesis building for Indo-Pacific coral reef fish

People involved: Elizabeth Jones Sbrocco (Boston University, USA)

Contact: Elizabeth Jones Sbrocco

Aim

To understand historical and modern-day influences on the spatial genetic structuring of coral reef fish populations in the Coral Triangle, a marine biodiversity hotspot.

Methods

I will use species distribution models to identify regions that may have served as common refugia for Indo-Pacific reef inhabitants during Pleistocene sea level lowstands. Distributions will also be modeled for current conditions and for those 6kya in order to identify regions that have remained stable habitat over the last 21kya. These models will be used to form phylogeographic hypotheses regarding the demographic history of populations and these hypotheses will be tested with mtDNA and microsatellite DNA analyses.

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Reconstruction of the dispersal patterns from the Caucasus forest refugia in Holocene

People involved: David Tarkhnishvili, Alexander Gavashelishvili, Marine Murtskhvaladze and levan Mumladze (Ilia State University, Tbilisi, Georgia)

Contact: David Tarkhnishvili

Aim

To model ancient ranges of relict animals and plants in the Caucasus Biodiversity Hotspot, known for high proportion of the endemic and relict species. Palinological data suggest that during the last glacial maximum, forest refugia were maintained only at the south-eastern Black Sea coast and not in the rest of the Caucasus Isthmus. However, multiple molecular genetic studies (Tarkhnishvili et al., 2000, 2001; Murtskhvaladze et al., in press) suggest that some species associated with mild humid climates ? including snails, salamanders, frogs, rock lizards, bears, and grouses, survived the Ice Age in isolated habitats both in the Lesser and the Greater Caucasus. Using suitable habitat models of the current distribution of these species, we plan to reconstruct post-glacial dispersal events and better understand the observed phylogeographic patterns in the entire Palearctics.

Methods

We plan to:

1. Develop spatial models of the target species based on the extant locality datasets, using presence-only and presence-absence approaches (Maximum Entropy, Mahalanobis Distance, Logistic Regression, Classification Tree, Artificial Neural Networks) and extant climate distribution (bioclimatic variables) or use already developed models (Tarkhnishvili et al., 2008, in press).
2. Construct haplotype (maternal and paternal) trees from both already existing and new DNA sequences.
3. Project the suitable habitat/range models on the climatic surfaces of the Last glacial Maximum and mid-Holocene.
4. Compare the ancient and extant species distribution ranges and estimate the effective size of the range fragments during the Last Glacial Maximum.
5. Reconstruct species-specific dispersal patterns and identify the most important refugial areas by combining range-modeling and molecular genetic methods.

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The role of the land masses in the Maritime Continent on the Last Glacial Maximum tropical atmospheric convection

People involved: Luis David Aimola and Hezi Gildor (Weizmann Institute of Science, Rehovot, Israel)

Contact: Luis David Aimola

Aim

We want to study the effect of expanded land masses of the Maritime Continent during the Last Glacial Maximum on the atmospheric convection over Indo-Pacific Warm Pool.

Methods

Using a intermediate complexity climate model (The QTCM - Quasi Equilibrium Climate Model) we are investigating the differences between the atmospheric convection during the Last Glacial Maximum and the present climate. We have found very interesting results around the Indonesian Archipelago and would like make new simulations using a different SST field for the LGM climate. We used until now the CLIMAP SST data for the LGM and would like to compare with some experiments made in the PMIP2 project using the PMIP2's SST field for the LGM.

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High resolution numerical simulations of southern mid and low latitude ice sheets from LGM to present

People involved: Nick Golledge, Andrew Mackintosh and Brian Anderson (Victoria University of Wellington, New Zealand)

Contact: Nick Golledge

Aim

To use PMIP2 modelled climate scenarios to guide ice sheet modelling experiments in Antarctica, New Zealand and potentially South America. PMIP2 data is unlikely to be used to directly force model runs, but is required for providing a realistic and reliable basis for perturbing high resolution present-day climatologies.

Methods

1. Identify present-day climatologies of ice sheet model domains from observational and RCM reanalysis data.
2. Use local palaeo-environmental proxy data and PMIP2 model simulations to establish likely deviations in range / patterns of temperature / precipitation fields during LGM climates.
3. Run ice sheet model simulations at variable resolutions with climatic boundary conditions guided by the above.

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Phylogenetic information for understanding and conserving the biodiversity in New Caledonia

People involved: Roseli Pellens (Museum National d'Histoire Naturelle, Paris, France)

Contact: Roseli Pellens

Aim

Our aim is to assess the effect of current and past climatic conditions on the phylogenetic distinctiveness of New Caledonia in order to better understand the diversification patterns and the evolutionary history, and to give guidelines for biodiversity conservation.

Methods

We will examine the effect of current climatic conditions and past Mid-Holocene (~6000 BP) on the phylogenetic diversity from 16 localities within New Caledonia.

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Climate change and New World megafaunal extinctions at the end of the last glacial cycle

People involved: Matheus de Souza Lima Ribeiro and Levi Carina Terribile (Universidade Federal de Goiás, Goiânia, Brazil)

Contact: Matheus de Souza Lima Ribeiro

Aim

The extinction of the megafauna during the Pleistocene-Holocene transition is a widely documented event over the world and the debate about this topic have been centred on environmental (climate change) and human-induced effects, or a combination of both. We are interested in exploring these two hypotheses for better understand the megafauna extinctions on the New World.

Methods

We will apply the PMIP2 data to modeling the climate envelope for several megafaunal taxa across different time periods and generating quantitative estimates of the relationship between the contraction of the megafauna's geographical range and climate change over last ice age.

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The palaeoecological history of an ancient endemic: where to from here for the koala?

People involved: Christine Adams-Hosking (The University of Queensland, Brisbane, Australia)

Contact: Christine Adams-Hosking

Aim

To model the current climate envelope for koalas and to predict the climate niche for this species at the last glacial maximum (c. 21 000 years ago).

Methods

We will develop a model of past (LGM) koala refugia using maximum-entropy niche-based modelling. Understanding past climatic impacts on koalas will assist in predicting future responses of koalas to climate change. This knowledge will help to predict areas of highest priority for the future conservation of this species.

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Water mass fingerprinting since the LGM

People involved: Yves Plancherel (Princeton University, Princeton, NJ, USA)

Contact: Yves Plancherel

Aim

Hydrographic analysis of the IPCC AR4 coupled models shows that not only will the temperature and salinity characteristics of the water masses evolve, but that these changes will affect the density difference between the main water masses. In these models, the density difference between specific water masses seems to be related to the sensitivity of each model to increasing anthropogenic atmospheric radiations. I would like to use LGM or other Holocene simulations to

1. investigate the relationships between water masses at these times when the MOC may have been reduced and water masses properties were different and
2. compare models to see if those with special sensitivities upon global warming are also special in LGM simulations

Methods

The core of the research relies on the interpretation of volumetric T/S distributions, linear regression methods applied on specific regions of the volumetric T/S shape and on the T/S representation of water mass formation. This latter step is mostly useful to identify water masses. The analysis is done globally, but special focus will be applied to the density and T/S differences of the North Atlantic Subpolar and Subtropical Mode Waters, the difference between the North Atlantic and the North Pacific mode waters and between North Atlantic Deep Water and Antarctic Intermediate Water.

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Geographic patterns in American birds driven by Quaternary climate oscillations

People involved: Mariana Rocha dos Santos and José Alexandre Felizola Diniz-Filho (Universidade Federal de Goiás, Goiânia, Brazil)

Contact: Mariana Rocha dos Santos

Aim

I will test if the geographical patterns of birds biological traits were driven by Quaternary climate oscillations.

Methods

I will use the PMIP2 Database as a source of glacial and interglacial temperature in order to identify the American bird's sister species that experimented different magnitude of climatic shifts and to test if the differences in biological traits between them can be explained by the magnitude of past climate changes.

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A reconstruction of temperature and sea level with 3-D ice-sheet models

People involved: Bas de Boer, R.S.W. van de Wal, R. Bintanja and L.J. Lourens (Utrecht University, The Netherlands)

Contact: Bas de Boer

Aim

To reconstruct temperature and sea level over the past 5 Million years with a set of four ice-sheet models. Ice-sheets are simulated on Antarctica, Greenland, North America and Eurasia and coupled with an inverse-forward modelling approach for which temperature is derived from deep-water benthic d18O records (see Bintanja et al., 2005, 2008).

Methods

Since variations in the deep-water during the Plio-Pleistocene are thought to be mainly forced from the NH, i.e. through NADW formation, the temperature derived from the deep-water records is the continental mean NH temperature, which is applied to the Eurasian and North American Ice-sheets (Bintanja et al., 2005).

To apply the calculated temperature over Antarctica and Greenland, a temperature difference from the NH continents needs to be included for these two regions. Results from the PMIP2 experiments (LGM, Holocene) will be used to establish this temperature difference for Antarctica and Greenland.

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Human cultural dynamics in late Pleistocene to mid-Holocene South America

People involved: James Steele (AHRC Centre for the Evolution of Cultural Diversity, University College London, UK)

Contact: James Steele

Aim

To compile a geo-referenced database of archaeological radiocarbon dates for human occupation in South America from the end of the Pleistocene to the mid-Holocene, and to examine patterns of covariance of site occurrences and material cultural attributes with reconstructed paleoenvironments, using modelled 21k and 6k climate variables as proxies to define boundaries (envelopes of uncertainty) for such reconstructions.

Methods

GIS for spatial analysis of covariance; various MCMC-based statistical techniques to predict dates of occurrence for the archaeological variables. Archaeological database is being compiled in consultation with regional experts.

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Analysis of the geographic distribution of the family Pettalidae of harvestman in New Zealand between the last glacial maximum and the present conditions

People involved: Marcos Longo and Gonzalo Giribet (Harvard University, USA)

Contact: Marcos Longo

Aim

We are investigating the relevance of various environmental conditions determining the areas of occurrence of individuals from the family Pettalidae (Arachnida, Opiliones, Cyphophthalmi) under present conditions, and our aim is to understand how the different environmental conditions during the last glacial maximum could have affected the range of this family in New Zealand.

Methods

We will use the maximum entropy model (MAXENT) to construct maps of probability of success finding individuals, based on geographic coordinates of individuals and maps of environmental variables. In this study we will combine the current occurrence data are based on fields observation and museum collections with current climatology based on reanalysis. Once the key environmental variables and their optimal range are determined, we will use data based on the LGM simulations to determine areas in which the Pettalidae species were likely to have persisted during the LGM.

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A Paleophytoclimatic model for Iberian Peninsula

People involved: Julián Gonzalo (Universidad de Valladolid, Spain), Ignacio García Amorena (Universidad Politécnica de Madrid, Spain) and Maria Fernanda Jiménez Buitrago (Universidad de Valladolid, Spain)

Contact: Julián Gonzalo

Aim

Project a phytoclimatic model for Iberian ecosystems functional types into LGM and MH downscaled paleoclimate spaces. Projections (EFTs paleodistribution) are compared with fossil pollen records.

Methods

A functional phytoclimatic model for Iberian Peninsula will be projected back into LGM and MH downscaled climate spaces, using a set of variables from the PMIP2 models and high resolution Iberian Climate Atlas. Projections will be compared to fossil records in the Iberian Pollen Database.

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Which paleoclimatic period explains better African Lepidopteran cereal stemborer Busseola fusca population genetic structure?

People involved: Stéphane Dupas (Intitut de Recherche pour le Dévelopement (IRD), Quito, Ecuador)

Contact: Stéphane Dupas

Aim

Determine which period is more correlated to actual genetic structure, and which has influenced more the population structure of the insect.

Methods

1. Predict present insect distribution with generalized additive models in R using present insect surveys across Africa (data: Bruno LeRü) and worldclim bioclimatic variables maps.
2. Predict insect distribution in Africa in mid-Holocene, last interglacial and last glacial maximum using the optimized model.
3. Predict, using these insect distribution maps and the software circuitscape, the connectivity at the different periods between localities where individuals have been genetically characterized individuals at microsatellite loci.
4. Test which period explains better the population structure by mantel tests between genetic differentiation statistics and predicted connectivity at the different periods.

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Extratropical thermal stratifications and moist convection at Last Glacial Maximum

People involved: Li Dong and Joseph Galewsky (University of New Mexico, Albuquerque, USA)

Contact: Li Dong

Aim

Two scaling theories, the dry baroclinic eddy theory and moist theory, have been previously proposed by numerous studies in predicting the static stability of extratropical troposphere, however, most of these studies were mainly focused on present day and global warming instead of a colder climate. Here we would like to investigate which of these two scaling theories works better in predicting the extratropical static stability in LGM. In addition, the role of moisture in determining the extratropical static stability will be investigated.

Methods

We plan to use seasonal LGM simulation outputs to

1. diagnose LGM midlatitude static stability,
2. compute dry static stability by dry baroclinic eddy theory,
3. compute moist static stability by moist theory,
4. and compare the contributions of moisture to midlatitude static stability in present day and LGM.

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Climate modeling prediction for the Gliridae and the Muridae families in the Palearctic and Southeast Asia regions

People involved: Alice Mouton (University of Liège, Liège, Belgium), Dormouse team project, Alice Latinne, Johan Michaux, Surachit Waengsothorn, Vincent Herbreteau

Contact: Alice Mouton

Aim

We plan to use niche modelling and pleistocene climate models to predict location and number of potential refugia for two of the most important rodents families in the Paleartic region and in the Southeast Asia: The Gliridae and the Muridae families.

Methods

ENM scenario exploration can provide a useful complement to molecular studies, offering a less subjective, spatially explicit hypothesis of past geographic patterns of distribution. In parallel to our previous and current phylogeographic analysis, we would like to develop modeling approaches (using ecological niche modeling methods). These methods would allow to estimate where different rodent species survived during the Quarternary ice ages by allowing species-environmental associations to be projected into the past (based on the reconstructed paleoclimate distribution provided by PMIP2) so that hypotheses about historical vicariance can be generated and tested independently with genetic data. The results would be extremely useful for conservation purposes as it would help to better estimate the risks or chance of survival of different rodent species in Europe and in SouthEast Asia in the future.

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Impact of global change on Neotropical grass distribution

People involved: Laurent Bremond (Institut de Botanique, Montpellier, France), Arnoud Boom (University of Leicester, UK) and Charly Favier (CNRS, France)

Contact: Laurent Bremond

Aim

To estimate how past and future CO2 and climate change affect the altitudinal C3/C4 grass balance in the Andes.

Methods

1. Calibration on present data: comparison of the altitudinal distribution of C4 grass species proportion with Collatz et al. physiological crossover temperature model and with C3/C4 biomass balance simulated by the DVGM LPJ-GUESS.
2. Sensitivity test of altitudinal crossover for future (IPCC climate models) and past (PMIP2 models) climates.

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Impacts of Tropical SST on ITCZ rainfall and East Asian summer monsoon at LGM

People involved: Yue Wang (State Key laboratory of Marine Geology, Tongji University, Shanghai, China)

Contact: Yue Wang

Aim

We propose to study the sensitivity of precipitation in tropical convergence zone and East Asian summer monsoon regions to different tropical SST distribution at LGM. In order to understand the atmospheric responses to variations of tropical SST, we plan to compare the LGM simulations of CAM3 with prescribed SST to paleoceanographic reconstructions and PMIP2 simulations.

Methods

We will first analyze the climatological precipitation differences and related atmospheric variations between different SST sensitivity experiments. Then independent paleoceanographic reconstruction and outputs from PIMP2 will be used for comparison and to access the uncertainty of LGM climate caused by SST boundary conditions.

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Phylogeography and ecological niche modeling of Mexican desert plants

People involved: Eduardo Ruiz-Sánchez (Instituto de Ecologia, Veracruz, Mexico)

Contact: Eduardo Ruiz-Sánchez

Aim

This project aims to reconstruct the phylogeographic structure of Mexican desert plants, dating the phylogeographies and to compare the phylogeographic pattern, with the past climate scenarios to understand the possible routes of gene flow in the Mexican deserts.

Methods

The phylogeographies will be done using cpDNA markers, the estimations of the divergence times will be done with BEAST using fossil calibrations points and with the comparisons between the divergence times and past climate scenarios constructed with Maxent will we understand the migration scenario and the possibles routes of colonization and gene flow.

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Physiological responses of plants to changing atmospheric CO₂ and climate since the late Pleistocene

People involved: Joy Ward, Juliana Medeiros and Laci Gerhart (University of Kansas, Lawrence, USA)

Contact: Juliana Medeiros

Aim

Our goal is to increase understanding of how climatic conditions affect the physiological responses of plants to low atmospheric carbon dioxide concentration [CO₂]. We are examining two key periods, the late Pleistocene, when [CO₂] was the lowest recorded in the modern history of land plants (180-200ppm), and the Holocene, when [CO₂] increased to a level equivalent to that of the pre-industrial period (260-280ppm).

Methods

We plan to use paleoclimate data from the PMIP database to interpret physiological measurements made on ancient plant macrofossils from two natural history collections. The first is a collection of Juniper wood remains from the Rancho La Brea Tar Pits radiocarbon dated between 40 and 10 kya. The second is a collection of Neotoma middens radiocarbon dated from 40-2 kya and originating from a broad range of environments covering most of the Western United States. Physiological responses of ancient plants will be determined using stable isotopes of carbon, oxygen and hydrogen.

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Sea ice in PMIP2 mid-Holocene simulations

People involved: Marit Berger and Jenny Brandefelt (Royal Technical Institute, Stockholm, Sweden)

Contact: Marit Berger

Aim

The idea of the project is to do a statistical study of the eleven PMIP2 simulations of mid-Holocene climate, in order to get a better picture of sea ice in existing climate models.

Methods

The simulated concentration, thickness and transport of Arctic sea ice will be evaluated in both an inter-model comparison and a comparison of simulated mid-Holocene climate to the respective preindustrial control climate for each model.

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Determining the geographic distribution of Colombian Pyrrhura to identify conservation gaps

People involved: Esteban Botero-Delgadillo, Carlos Andrés Páez and Nicholas Bayly (SELVA: Research for Conservation in the Neotropics , Colombia)

Contact: Esteban Botero-Delgadillo

Aim

As a first approximation to defining the conservation status of the genus Pyrrhura (Psittacidae) in Colombia, this study aims to predict the past, current and future geographic distribution of its species and subspecies with four main intentions: to demonstrate that under predictions based on past and present bioclimatic parameters, the populations of most subspecies are completely isolated and thereby are independent conservation units; to estimate potential distributions and loss of habitat, to show that for various species in the genus the situation is more critical than previously considered; to identify priority areas for their protection and conservation gaps in geographic terms; and to predict the status for each population under continued anthropogenic pressures and different climate change scenarios using geographic distribution models based on future bioclimatic parameters.

Methods

We would use the paleoclimatic data (both the Last glacial maximum and the Mid-Holocene) to model the past geographic distribution of the recognized species and subspecies of the genus Pyrrhura (Psittacidae) in Colombia, using the Maximum Entropy (MaxEnt) algorithm and all the available geographic references from public databases and personal observations. This would be used to predict if before and after the last glacial period, the conditions of tropical dry forests and lowland and montane humid forests in northern Colombia and the inter-Andean valleys, promoted the isolation of humid forest populations of Pyrrhura. Distribution models supporting current (with WorldClim bioclimatic data) and past (paleoclimatic conditions) isolation among populations will be used to determine if each population and/or subspecies can be considered as a valid conservation unit, regardless of their recognized species conservation status.

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The role of atomic chlorine in the marine boundary layer in glacial-interglacial changes in delta13C(CH4)

People involved: James Levine, Eric Wolff, Anna Jones and Louise Sime (British Antarctic Survey, Cambridge, United Kingdom)

Contact: James Levine

Aim

To assess the potential for wind-driven changes in sea salt aerosol production to contribute to glacial-interglacial changes in delta13C(CH4).

Methods

Use pre-industrial (PI) and last glacial maximum (LGM) surface winds, as simulated by PMIP2 models, to explore changes in the atmospheric loading of sea salt aerosol between the LGM and the PI. These can be used to estimate changes in the concentration of atomic chlorine (Cl) in the marine boundary layer, which can be related to changes in delta13C(CH4) as a result of changes in the fraction of methane oxidised by Cl.

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Hypsithermal distributions of Periodical Cicada (Magicicada spp.) Broods.

People involved: John Cooley (Ohio State University, Columbus, OH, USA)

Contact: John Cooley

Aim

Periodical cicadas (Magicicada spp) have a uniquely complex biogeography involving life cycles, species, and broods. The biogeography of these different units have long been used to make inferences about postglacial climate history, but these inferences have been limited by the inaccuracy of distribution maps and by the lack of formal methods of analysis. The periodical cicada mapping project (www.magicicada.org) has compiled a database of over 50,000 records of periodical cicada emergences and is in the process of making entirely new distribution maps to replace the 19th century USDA maps and their derivatives currently in use. The coauthors of these new maps are also working on the first ecological niche models of periodical cicadas, to be published soon. These first models are based on present-day climate conditions, so the next step is to use models of past climate data to make inferences about glacial refugia and Hypsithermal distributions of periodical cicadas. For this, the Paleoclimate Modeling Intercomparison Project database seems ideal. This project will contribute to several papers currently in preparation.

Methods

Output from the periodical cicada database (hydrodictyon.eeb.uconn.edu/projects/cicada/databases/magicicada/magi_search.php) is GIS-compatible and will be used along with existing ENM generated with MaxEnt to search for evidence of greater range extent during the period 8000-2000bp than at present.

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PrediCtoR: estimating DNA degradation in ancient biomaterials

People involved: David Harker and Matthew Collins (University of York, York, UK)

Contact: David Harker

Aim

We are working on a model to estimate DNA degradation in ancient biomaterials and we would like to use PMIP2 paleoclimatic data to generate integrated thermal histories of samples in order to estimate the contribution of temperature variation to DNA depurination.

Once functional, the model will be made freely available for use/evaluation online via an interactive web application.

PrediCtoR (thermal-age.eu): "A novel decision-making software tool will be developed to help collections managers and Users to quantify the risks associated with destructive analysis of specimens. PrediCtoR will be delivered via a web-based interface and will forecast the success of PCR amplification of DNA using a predictive model of DNA decay. PrediCtoR will be a simple-to-use, inexpensive-to-operate, non-destructive tool designed to enhance the conservation of collections, by preventing unnecessary destructive sampling."

Methods

We plan to use 6ka and 21ka global ground surface air temperature anomaly data along with comparable modern data to scale a global mean temperature curve to best fit the sample location, and then to calculate an integrated thermal history for the sample.

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Modeling tree and parasite distributions in eastern North America during the Pleistocene

People involved: Yi-Hsin Erica Tsai (Louisiana State University, Baton Rouge, LA, USA)

Contact: Yi-Hsin Erica Tsai

Aim

To predict the locations of refugia at the LGM and to understand subsequent range changes.

Methods

I intend to project ecological niche models onto past climate scenarios to locate putative refugia and migration routes. The results will be interpreted alongside genetic and fossil pollen evidence to understand how climate changes affected population demography, range changes, and population structure.

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Diversity patterns in mediterranean-type ecosystems: the role of climatic and geomorphic stability

People involved: Peter Bradshaw, Richard Cowling (Nelson Mandela Metropolitan University, Port Elizabeth, South Africa), Jonathan Colville (South African National Biodiversity Institute, Kirstenbosch, South Africa), Simon Ferrier (CSIRO, Canberra, Australia), Felix Forrest, Steve Hopper, Rhian Smith (Kew Gardens, UK), Serban Proches (University of KwaZulu Natal, South Africa) and Phil Rundel (Dept Biology, UCLA, USA)

Contact: Peter Bradshaw

Aim

The aim of our project is to investigate the role of historical and contemporary climatic and geomorphic stability in explaining the diversity patterns associated with the world's five mediterranean-type ecosystems (SW Australian Botanical Province, Cape Floristic Region, California Floristic Province, Central Chile and the Mediterranean Basin) all of which are recognised biodiversity hotspots. The study will use both contemporary and historical variables to develop a model to explain patterns of taxic and phylogenetic diversity in these mediterranean-type ecosystems.

Data and methods

Historical climatic data (specifically PREC, TAVE, TMAX and TMIN so as to derive BIOCLIM variables), for the three time intervals available (6K BP, 21K BP and 140K BP), in conjunction with geomorphic data will be analyzed in relation to several diversity measures (species richness, number of endemics, species turnover, and phylogenetic diversity).

Spatial and temporal variability of key explanatory variables associated with mediterranean ecosystems (e.g. BIOCLIM 19 etc.) will be investigated as a proxy for climatic stability in these regions.

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Modeling the paleodistribution of the Passerina bunting hybrid zone

People involved: Matt Carling (Cornell University, Ithaca, NY, USA)

Contact: Matt Carling

Aim

To predict the distribution of the hybrid zone between Indigo (Passerina cyanea) and Lazuli (Passerina amoena) buntings during the Last Glacial Maximum and the mid-Holocene.

Methods

I will use data on the current distribution of the Passerina bunting hybrid zone to identify the relevant environmental variable associated with it's geographic location using species distribution methods. These current data come from my work on understanding the genetic structure of this hybrid zone and will be expanded using data from museum specimens and the literature to build a comprehensive model of its current distribution. This 'species' distribution model (really a 'hybrid zone' distribution model) will then be projected onto the climate estimates from the last glacial maximum and the mid-holocene to understand both the paleodistribution of the hybrid zone and how it has changed over time.

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Integrating species distribution modeling and phylogeography to assess the impact of climate change on past and future distributions of an alpine-arctic plant

People involved: Brenna R. Forester, Andy Bunn and Eric DeChaine (Western Washington University, Bellingham, WA, USA)

Contact: Brenna R. Forester

Aim

We are investigating the impact of climate change on the past, present and future geographic distribution and genetic variability of an alpine-arctic plant, Rhodiola integrifolia. We are testing a suite of hypotheses about the importance of climate in determining the rate of gene flow between disparate populations from glacial refugia to modern distributions. We can then establish if projected future habitat will be viable given increasing isolation as the climate warms.

Methods

Using an ensemble modeling approach (multiple model algorithms and multiple climate data sets), we are developing models that predict probability of species occurrence as a function of present, past and future climates. We are testing these models with genetic data using a coalescent framework, providing a robust understanding of modern patterns of genetic variability, while helping constrain possible scenarios of future population viability. These data also provide an independent assessment of the effectiveness of the model as a predictor of future distributions. We will be using PMIP 2 climate data for the paleodistribution component of our modeling.

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East African hydroclimate at 6 ka

People involved: Jessica Tierney (Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA), Sophie Lewis (ANU, Australia), Allegra LeGrande (NASA GISS, USA)

Contact: Jessica E. Tierney

Aim

Compare PMIP simulations of ocean-atmosphere dynamics and climatology in the Atlantic and Indian Ocean basins at 6 ka with proxy-derived inferences of pluvial conditions along the East African Rift Valley.

Methods

We plan to:

1. Analyze changes in sea-surface temperatures, winds, precipitation, moisture transport, etc. in the 6 ka OAGCM results.
2. Compare the model-simulated changes at 6 ka with proxy estimates of P-E and changes in the isotopes of precipitation in tropical East Africa.
3. Use this comparison to assess the relative importance of Indian Ocean vs. Atlantic Ocean processes in affecting East African hydroclimate on orbital timescales.

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The postglacial expansion of the crested newt Triturus cristatus superspecies

People involved: Ben Wielstra, Jan W. Arntzen, Andrew Skidmore and Bert Toxopeus (International Institute for Geo-Information Science and Earth Observation, Enschede, Netherlands)

Contact: Ben Wielstra

Aim

The crested newt Triturus cristatus superspecies comprises a group of closely related species which are parapatrically distributed. Niche differences most likely underlie how the different species geographically exclude each other. Considering climate dynamics, this case makes for an interesting evolutionary struggle in space and time. We aim to reconstruct the historical biogeography of the crested newts.

Methods

To obtain insights in the past distribution of the crested newts, we combine a phylogeographical survey with ecological niche modeling. We compare whether the signal obtained by these two independent approaches post points to the same scenario. In particular, we examine signs of relatively recent, post-glacial stability or expansion, as we expect the different members of the superspecies show either patterns of 'northern purity' or 'southern richness'.

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Hydrological reconstruction and Ecosystem development in Florida during the Holocene

People involved: Stefan C. Dekker, Hugo J. de Boer, Emmy I. Lammertsma, Rike Wagner-Cremer (Utrecht University, dept Environmental Sciences, The Netherlands)

Contact: Stefan C. Dekker

Aim

Paleo-ecological evidence show that the onset of peat formation started at 5200 BP for several sites in Florida. Peat development is non-linear with thresholds in the system. Two alternative hypotheses are found in literature to understand the onset of peat formation; the Mid-Holocene high stand (change in precipitation) and the sea level rise. Around 3500 BP a second shift in peat formation is found, maybe attributed to the start of modern-day ENSO intensification We aim to reconstruct the causal effect of the onset of peat formation in Florida.

Methods

LGM, Mid-Holocene and present precipitation and evaporation data will be used to force our model of peat development, and will be compared with paleo-ecological evidence from lakes and marshes in Florida.

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Past climate as a driver of macroecological biodiversity patterns

People involved: Daniel Kissling, Signe Normand, Anne Blach-Overgaard, Michelle Greve, Camilla Fløjgaard, and Jens-Christian Svenning (Ecoinformatics and Biodiversity Group, Aarhus University, Denmark)

Contact: Jens-Christian Svenning

Aim

It is increasingly recognized that long-term history may play an important role, in addition to current climate, in determining macroecological patterns of species distributions and species richness. We will use estimates of past climate (a key aspect of history) to better explain current patterns of species diversity and to improve our understanding of potential impacts of future climate change on biodiversity.

Methods

Our projects span a broad selection of taxa and their distributions at regional, continental and global spatial scales. PMIP2 estimates of past climate will be used to compute measures of past bioclimatic conditions as well as climatic stability across time and space. These data will be used to estimate Late Quaternary range dynamics and the effects of past climate on current species diversity patterns.

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Ecological Niche Model Predictions of LGM refugia for the Vinous-throated Parrotbill (Paradoxornis webbianus) and Hwamei (Garrulax canorus)

People involved: Pei-Jen Shaner, Tzu-Hsueh Tsao and Shou-Hsien Li (Pei-Jen Shaner, Tzu-Hsueh Tsao and Shou-Hsien Li)

Contact: Pei-Jen Shaner

Aim

We will evaluate potential LGM refugia for the Vinous-throated Parrotbill (Paradoxornis webbianus) and Hwamei (Garrulax canorus) in Asia.

Methods

We have used phylogeny to reconstruct LGM refugia for the Vinous-throated Parrotbill (Paradoxornis webbianus) and Hwamei (Garrulax canorus) in Asia. We would like to use ecological niche model (ENM) to compare ENM-based reconstructions of LGM refugial locations with those resulting from our earlier predictions based on molecular evidence. In order to reconstruct ENM-based LGM refugia, we need to project present-day potential distributions of these two species to LGM climate conditions.

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The Impact of Quaternary Climate Change on the Distribution of a late successional Rainforest Conifer (Podocarpus elatus)

People involved: Rohan Mellick (National Herbarium of NSW, Sydney, Australia)

Contact: Rohan Mellick

It is not compulsory any more to supply a (full) project for accessing the PMIP2 data.
Get in touch with the contact person for this project if you need more details!

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Consequences of polyploidy: phylogeny, phyloecology and expression of duplicated genes in Leucanthemum Mill. (Asteraceae, Anthemideae)

People involved: Kamil Konowalik (Institute of Botany, University of Ratisbon, Regensburg, Germany)

Contact: Kamil Konowalik

It is not compulsory any more to supply a (full) project for accessing the PMIP2 data.
Get in touch with the contact person for this project if you need more details!

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