Multivariate Paleoclimatic Analysis in Southern South America with Emphasis on Transitional Periods

科罗拉多大学Am-9321857 Markgraf，Vera White，James W.C.标题：南美洲南部的多变量古气候分析，重点是过渡期该奖项支持对南美洲南部泥炭岩心的多变量古气候研究，使用花粉和稳定同位素分析。这些岩芯被认为包含了自上一次冰川/间冰期过渡以来的连续记录。到目前为止，对比格尔海峡北纬55度的一个泥炭岩芯进行的高分辨率联合分析结果表明，花粉地层学提供了更好地评估稳定同位素比的前景，并且联合方法大大增加了古气候信息。这项工作的目标有三个：1)通过对苔藓的实验实验室研究和对现代沼泽的深入实地研究，完善稳定同位素数据的校准；2)通过使用相同的方法分析来自同一一般气候区的其他记录，确认古气候变化的历史；以及3)通过分析南美洲南部不同地区以及北半球的其他记录，确认过去二氧化碳的变化记录。将几个岩心的古气候和古二氧化碳浓度记录结合起来，将有助于更好地理解气候突变事件的机制和动力学。

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.