PMIP 2 @ INQUA 2003

Dear PMIP Colleagues,

We will be convening a symposium on Earth system models, palaeo-observations, and past global changes at the International Quaternary Association (INQUA) Congress, to be held in Reno (USA) in July 2003. The INQUA Congress runs from 23^rd to 30^th July, and the ESM symposium (see description below) will be on Friday 25^th July.

Symposium: Earth System Models, palaeo-observations, and past global changes

The Palaeomodelling Intercomparison Project (PMIP), sponsored by WCRP and IGBP-PAGES, has actively promoted the use of standardised global palaeoenvironmental data sets to evaluate model simulations. In the first round of PMIP, 18 modelling groups participated in standardised model experiments for 6000 yr B.P. and 21,000 yr B.P. (LGM) using either atmospheric general circulation models or atmospheric-mixed layer ocean models. In the second phase of PMIP, the plan is to carry these model intercomparisons further and specifically to examine how coupled ocean-atmosphere models, and ocean-atmosphere-vegetation models perform when forced with the same boundary conditions. New palaeodata sets (e.g. for 3D ocean conditions and land-surface conditions) are needed to evaluate these simulations. Comparison of the PMIP II simulations and such palaeoenvironmental data sets within the framework of the proposed session will provide an exciting opportunity to see how far state-of-the-art models can explain past climate changes and how far the results are model-dependent.

We see this as an opportunity to showcase ongoing work within PMIP, and in particular to highlight progress in the modelling of palaeoclimates using fully-coupled (OA and OAV) models and in model evaluation using palaeoenvironmental data. The symposium will be in two parts: a morning session with 8-10 presentations (a mixture of invited and contributed talks) and an afternoon poster session. We would very much like to encourage you to contribute to this symposium, and to encourage your colleagues and students to take part.

INQUA is striving to bring the modelling and data communities closer together, so there will be several other symposia at the Congress which are likely to be of interest to us all, specifically:

• Saturday 26^th : Observations and modelling of ENSO and other aspects of short-term climate variability during the Holocene (Convenors: Zhengyu Liu and Keith Briffa).
• Monday 28^th : Earth system dynamics: Modelling Quaternary environmental change (Convenors: Mike Coe, Sharon Cowling, Andy Ridgwell).
• Tuesday 29^th : Observations and modeling of the palaeodust cycle (Convenors: Ina Tegen and Karen Kohfeld).
• Wednesday 30^th : Changes in atmospheric trace gases and aerosols on glacial-interglacial time scales: a key challenge for Earth system models (Convenors: Colin Prentice and Dominique Raynaud).

Again, these symposia will consist of morning sessions with presentations and afternoon poster sessions.

In practical terms, the deadline for registration for the INQUA Congress is March 31^st. Note: there is a discount for early registration (deadline: January 31^st). If you wish to submit an abstract for the PMIP-related symposium (either for a talk or a poster), you need to take care to make it clear when you register (online registration via the INQUA website. It would be helpful if you could send a copy of your abstract to us (Pascale Braconnot + Sandy P. Harrison) at the same time, so we can work on the programme.

We hope to be able to use the opportunity of the INQUA Congress to hold a PMIP planning meeting (probably on the evening of Friday 25^th July) and to use this to continue the fruitful discussions begun in Cambridge last year. So, we hope you will be able to fit INQUA into your schedule and look forward to seeing as many of you as possible in Reno in July.

With very best wishes,

Sandy Harrison and Pascale Braconnot