Collaborative Research: Paleohydrology Across Central Alaska: A Multiproxy Approach to Lake-Level Records

题目：横跨阿拉斯加中部的古水文：湖位记录的多代理方法本项目的主要目标是产生阿拉斯加中部新的多代理古气候记录，以检验关于18ka至今降水-蒸发平衡变化原因的假设。该奖项支持以下研究：(i)扩大具有年代际到世纪尺度湖泊水位数据的站点网络，以确定降水-蒸发平衡变化的时空格局；（ii）确定过去2000年沙丘湖封闭盆地的年至年代际湿度平衡波动。这些记录对于了解北极的长期大气动态和评估降水-蒸发平衡变化的意义是必要的。通过一系列沉积学、地球化学、磁性、花粉含量、稳定同位素组成的研究，以及北极地区首次生物标志物化合物的分析，重建该地区全新世气候历史。通过大型化石和花粉的137Cs、210Pb和AMS 14C测量，对湖芯进行了高分辨率测年。

ATM-9707625 Abbott, Mark B. University of Massachusetts ATM-9709398 Finney, Bruce P. University of Alaska Title: Paleohydrology Across Central Alaska: A Multiproxy Approach to Lake-Level Records The primary objective of this project is to produce new multi-proxy paleoclimate records from Central Alaska to test hypotheses concerning the cause of shifts in the precipitation-evaporation balance from 18 ka to present. The award supports research to: (i) expand the network of sites with decadal to century-scale lake- level data to identify the spatial and temporal pattern of changes in the precipitation-evaporation balance and (ii) identify fluctuations in the moisture balance for the past 2000 years at annual to decadal-scale from closed basin Dune Lake. These records are needed to understand the long-term atmospheric dynamics of the Arctic and to assess the significance of shifts in the precipitation-evaporation balance. The Holocene climate history of the region will be reconstructed with a series of studies analyzing the sedimentology, geochemistry, magnetic properties, pollen content, stable isotopic composition, and for the first time in the Arctic, biomarker compounds. The lake cores will be dated at high- resolution by 137Cs, 210Pb and AMS 14C measurements on macrofossils and pollen.