Collaborative Research on Analysis of a High-Resolution Pollen Record from the Dunde Ice Cap of Western China

从冰川中提取的冰芯为几万年来气候、植被和其他现象的变化提供了重要的信息来源。对氧同位素的分析可以产生温度的代用物，对可溶性和不可溶性气溶胶的分析可以提供风力和风向、火山活动和干旱的指示。对年冰层厚度的测量可以提供有关降水模式的宝贵信息。冰芯中的花粉还没有得到广泛的研究，但这些细颗粒提供了关于过去植被模式的巨大潜力。本合作研究项目将从中国西部邓德冰盖提取的冰芯中提取高时间分辨率的长期花粉记录。这一花粉记录将补充其他气候代用数据，提供近10万年来气候和相关变量的详细区域变化历史。将特别强调利用这些数据来检查植被对地球轨道变化引起的季风环流变化的反应。还将进行分析，考虑植被对“小冰期”的降温和晚更新世和全新世期间温室气体引起的变暖的反应。该项目将为重建和分析过去10万年的气候变化提供宝贵的新数据。因为像邓德冰帽这样的亚热带冰川比高纬度地区的冰川含有更多的花粉，它们允许对气候和植被的变化模式进行相对较高的时间精度的检查。它们还提供了有关当前变化率的宝贵数据来源，这些数据可用于帮助验证许多不同的气候模型。＊＊＊

9412262 THOMPSON Ice cores drawn from glaciers provide an important source of information about changes in climate, vegetation, and other phenomena over tens of thousands of years. Analyses of oxygen isotopes can generate proxies for temperature, and analyses of soluble and insoluble aerosols can provide indications of wind strength and direction, volcanic activity, and drought. Measurement of the thickness of annual ice layers yield valuable information about precipitation patterns. Pollen contained within ice cores has not been studied as extensively, but these fine particles offer great potential as sources of information about past patterns of vegetation. This collaborative research project will extract a long-term pollen record with a high temporal resolution from ice cores extracted from the Dunde Ice Cap in western China. This pollen record will supplement other climate proxy data to provide a detailed regional history of changes in the climate and related variables over the last 100,000 years. Special emphasis will be placed on the use of these data to examine vegetational responses to monsoon circulation changes induced by changes in the Earth's orbit. Analyses also will be undertaken to consider vegetational responses to cooling during the "Little Ice Age" and to greenhouse gas-induced warming during the late Pleistocene and Holocene periods. This project will provide valuable new data to facilitate the reconstruction and analyses of climatic changes over the last 100,000 years. Because subtropical glaciers like the Dunde Ice Cap contain far more pollen than do glaciers at higher latitudes, they permit examinations with relatively great temporal precision of changing patterns of climate and vegetation. They also provide valuable sources of data regarding current rates of change, and these data can be used to help validate a number of different climatic models. ***