Short Report on the 1. EPILOG Workshop to the IMAGES Office

The EPILOG working group of the IMAGES program chaired by E. Bard and A. Mix was constituted in Dezember 1997 in order to establish a new and comprehensive look at the paleoenvironments of the last Ice Age. The major aim of this working group is to foster a revision of global reconstructions of the Ice Age earth. This should be carried out by assembling international groups of paleoclimatologists to join this initiative, and to discuss and review the progress made for paleoenvironmental reconstructions for the last Ice Age during the last two decades since the completion of the CLIMAP LGM project.

Following this premise, an international workshop was held at the HANSE Institute for Advanced Studies, Delmenhorst, Germany, May 3-6, 1999. Convened by R. Schneider, E. Bard and A. Mix this 1. EPILOG workshop was entitled "Global Ocean and Land Surface Temperatures during the last Ice Age" and focused on three major issues:

1. To establish an international consensus on the definition of the "Ice Age" or "LGM (Last Glacial Maximum)" time slice for orientation of any further syntheses considering this period.

2. To discuss and critically evaluate the potential of commonly used and new techniques for estimation of past surface temperatures on the continents and in the ocean.

3. To initiate a new global synthesis of Ice Age surface temperature and the generation of new maps. In this context it was particularly intended to agree on certain criteria for the application of the different paleotemperature methods as well as on procedures for data archiving to allow international access to the new data by other scientific communities.

Due to the generous financial sponsorship by the HANSE Institute at Delmenhorst, the IMAGES and PAGES programs, and the Special Research Project 261 at Bremen University 51 scientist from Australia, Canada, France, Germany, Great Britain, Spain, The Netherlands, and USA were able to participate. The topics cited above were comprehensively discussed in plenary and group discussions. This was done after short individual oral and poster presentations introduced the entire audience to the following themes:

- Definition of the Ice Age time slice, - New or improved classical methods for paleotemperature estimation, - New regional and basin-wide data syntheses available for the ocean and the continents, - Results of recent GCM model runs for the LGM (e.g. PMIP), - Introduction to international paleoclimate data archives like BIOME 6000, NDGC NOAA, PANGAEA, including the IMAGES data curation.

The participants of the workshop agreed on a new definition of the Ice Age time slice which is exclusively orientated to the time of the maximum extent of global ice volume in accordance with glacial sea-level low stand. The last Ice Age time slice has been fixed now as the interval between 19,000 and 23,000 cal years (16.0-19.5 14C radiocarbon years, CALIB4), centered at 21,000 cal years BP. It was further agreed that existing surface sediment data sets for the calibration of the various temperature methods should be made accessible to the different research groups applying these methods in different ocean basins. This should allow significant progress in statistical evaluation of the performance of different transfer-function or modern-analog techniques on the same calibration data set and to enable comparison of geochemical methods with those based on microfossil or floral assemblages. The detailed results and the outcome of this first EPILOG workshop will be reported in three steps. First, this short summary will be available on the IMAGES and PAGES web sites providing also links to different ongoing activities dealing with the reassesment of the environmental conditions during the last Ice Age. These are, amongst others, the GLAMAP (Glacial Atlantic Ocean Mapping) and the TEMPUS (Sea Surface Temperature Evolution Mapping based on UK37 Stratigraphy) projects for the surface ocean, the BIOME 21k Paleovegetation Mapping on the continents, and the PMIP (Paleomodeling Intercomparison Project). Second, the agenda of the workshop, including all abstracts of the talks and poster presentations, as well as the summaries of the discussion groups, will be available on personal request as a report from the Fachbereich Geowissenschaften, Bremen University. Third, a short review paper on the status of the re-asssesment of the "Ice Age" temperature reconstructions as it turned out during the 1. EPILOG workshop will be submitted to Quaternary Science Reviews.

The 1. EPILOG workshop can be considered as a sucessfull initiation of a new global synthesis of ocean and continent paleotemperatures for the last Ice Age. After very encouraging and fruitful discussions on the topics listed above, a general consensus between the leading international teams working in this field could be achieved and general guidelines were formulated for the compilation of new global maps of ocean and continent paleotemperatures by integrating the different methods and new regional or basin -wide compilations which will exist in the next future. These could also serve as an orientation for other scientists or teams who would like to participate in the IMAGES Working Group or contribute to the reassessment of paleoenvironmental conditions during the last Ice Age. The 2. EPILOG workshop will be held in September 2000 in order to reconcile ice cover druing the last Ice Age.

The Convenors

Edouard Bard
Alan Mix
Ralph Schneider