********************************************* PALEOCLIMATE MODELING INTERCOMPARISON PROJECT ********************************************* Workshop letter / No. 2 ---------------------------- 6 June 1995 Dear PMIP workshop participant, Thanks to all of you for your interest in the PMIP workshop. We send you both practical and scientific information concerning the workshop scheduled for 1-6 October 1995 in Collonges la Rouge (France). Participants will be expected to arrive Sunday, October 1 and depart after the morning session on Friday, October 6. All participants receiving travel support are asked to purchase tickets early enough to obtain a reduced economy fare (usually involving certain restrictions or penalties). You will receive further travel arrangement specifications before the end of June. To get to Collonges la Rouge you have to fly either to Paris or Toulouse (France) and then take a train to Brive la Gaillarde which is the nearest town near Collonges. The train can be taken either from Paris at the station "Austerlitz" in the center of Paris or from Toulouse-Matabiau (in the centre of Toulouse). Trains leave approximately every 3 hours. If you have trouble obtaining information about the trains, please contact us. >From the scientific point of view ********************************* We have several objectives that with your active participation we hope to accomplish. Each participant will be expected to contribute certain model output, and we will need to carefully structure the workshop to facilitate interactive and productive discussion. Here we outline our preliminary ideas concerning the workshop in hopes of provoking you to provide alternative suggestions and other input and feedback. The main goals of the workshop are to: * share results from the PMIP simulations in order to identify common responses, discover where disagreement among models is large, get an idea of the range of responses, and identify in individual models any unusual or extreme responses that might warrant further investigation. *identify issues of common interest and form subprojects for further study. * share methodologies and approaches for analysis and diagnosis of paleoclimate simulations and propose (or demonstrate) strategies for intercomparison of model results and comparison of results to observations. Our tentative plans are to organize the workshop according to time period (21 ka BP or 6 ka BP). We plan to schedule two sessions, separated by a generous break, each morning and afternoon (except Wednesday, which will be reserved for informal activities). We want to avoid a "show and tell" workshop and thus expect only a handful of extended talks such as : - overviews of past modeling work with emphasis on what scientific issues were addressed or raised, - overviews of the availability and quality of the paleoclimate data for the period - presentations of preliminary attempts to intercompare PMIP model results, and/or descriptions of specific methodologies or special diagnostics useful for analyzing results. During such talks it is hoped that specific PMIP subprojects ideas will be proposed. The workshop participants will also divide into working groups which will address several specific questions and will allow further sharing of model results (Below is a preliminary list of issues that might serve to focus discussion in the working groups). One important task of each working group will be to suggest subprojects which will subsequently be discussed in a plenary session. To help discussions and first model-model comparisons, we propose to gather a standard set of model figures for each model and prepare a booklet to be distributed at the workshop. Therefore, WE WILL THEN NEED YOU TO PROVIDE A STANDARD SET OF FIGURES to LMCE (S. Joussaume) by 31 August 1995. The list of figures and the format will be specified in a forthcoming newsletter. The list will at least include classical diagnostics such as changes in surface air temperature, precipitation, P-E, sea level pressure, geopotential height at 500 hPa. Please tell us as soon as possible which other specific diagnostics should be required from each model. We may also need to spend some time during the week discussing the mechanics and ground rules for archiving and sharing data, publishing or formally presenting PMIP results, and learning about what lessons AMIP can teach us concerning these things. Preliminary list of issues --------------------------- We have begun to compile a list of issues, questions, and areas of interest concerning each of the PMIP periods, which we hope will focus the discussion during the PMIP workshop and help in defining subprojects. Our preliminary list follows: 6 ka BP experiment: * monsoon-related issues including enhanced summer warming of continents, changes in the seasonal cycle of the monsoon, changes in the Hadley/Walker circulation * winter time circulation changes * comparisons with paleoclimate data 21 ka BP experiments: * midlatitude northern hemisphere circulation (split jet, change in storm tracks, intensification of zonal winds) * SST and seaice response vs. CLIMAP (calculated SST experiment) * polar amplification and tropical sensitivity (calculated SST experiment). * monsoon changes * is prescribed glacial ice distribution consistent with meteorology (precipitation and temperature) simulated by models? * what are changes in implied ocean heat transport (fixed SST experiment)? * comparisons with paleoclimate data Please help us extend or ellaborate on the above. To summarize, we need from you : ------------------------------- AS SOON AS POSSIBLE : * suggestions for issues to be discussed at the workshop and/or subprojects and diagnostic strategies that you would like to promote for PMIP * abstracts before JUNE 30 BUT ONLY concerning : - preliminary PMIP intercomparisons of two or more models - presentations of diagnostic strategy or intercomparison methodology that you think might be central to one or more subprojects, - proposals for a specific subproject, FOR THIS SUMMER ---------------- * the standard set of figures as mentioned above (AUGUST 31) * model output to be contributed to the PMIP DATABASE for model results, which will be necessary for systematic model-model comparisons If possible we would like to begin to receive data from your model simulations at PCMDI in the early part of the summer to be able to produce some first model-model comparisons at the workshop. Requirements concerning data structure and the procedure to transfer it to PCMDI will be specified in a newsletter to be distributed soon. We hope to hear from you soon in answer to the above requests. The sooner we receive your input, the easier it will be to reach a consensus concerning the structure of the workshop. We believe that the workshop's success depends largely on your active participation, both before and during the week of the workshop. Please do your part. We are looking forward to your help in making this first PMIP workshop a success. Best regards, Sylvie Joussaume and Karl Taylor ----------------------- List of participants ----------------------- PMIP Co-Coordinators: S. Joussaume K. Taylor PMIP Advisory Committee: L. Gates J. Kutzbach J. Mitchell D. Rind W. Prell C. Prentice A. Street-Perrott Data-Model Intercomparison Subcommittee: J. Guiot S. Harrison P. Bartlein NGDC Representative : R. Webb Workshop Organizing Committee (LMCE) P. Braconnot G. Ramstein N. de Noblet V. Masson PMIP Participants: A. Abe-Ouchi CCSR T. Broccoli GFDL D. Buwen UGAMP K. Herterich Bremen U. C. Hewitt UKMO S. Hostetler US Geological Survey D. Jolly Lund U. / Marseille A. Kislov Moscow Univ. A. Kitoh MRI M. Lautenschlager MPI M.F Loutre 2-D LLN B. McAvaney BMRC N. McFarlane CCC B. Oglesby CCM1 B. Otto-Bliesner GENESIS II J. Oh YONU D. Pollard GENESIS II M. Schlesinger Illinois L. Sloan GENESIS I J. Syktus CSIRO P. Valdes UGAMP M. Verbitsky Illinois Proposals of special diagnoses : C. Genthon LGGE