Abstract ATM-9321857 Markgraf, Vera White, James W.C. University of Colorado Title: Multivariate Paleoclimatic Analysis in Southern South America with Emphasis on Transitional Periods This award supports a multivariate paleoclimate study, using pollen and stable isotope analyses, of peat cores from southern South America. These cores are believed to contain a continuous record since the last glacial/interglacial transition. Results obtained to date from the combined high resolution analyses of one peat core, at latitude 55o in the Beagle Channel, indicate that the pollen stratigraphy provides the perspective against which stable isotope ratios can be better evaluated and that the combined approach greatly augments the paleoclimatic information. The goal of the present effort is threefold: 1) refine the calibration of the stable isotope data by both experimental laboratory studies with mosses and indepth field studies of modern bogs; 2) confirm the history of paleoclimatic change by analyzing other records from the same general climatic region using the same approach; and 3) confirm record of past changes in pCO2 by analyzing other records from different regions in southern South America and also from the northern hemisphere. The combination of records of paleoclimatic and paleo-carbon dioxide concentrations from several cores will lead to a better understanding of the mechanisms and dynamics of abrupt climate change events.
