Tree-Ring Analysis of Regional to Large-Scale Paleoclimate

该奖项支持了美国东南部一系列千年树木年轮年表的发展。这些长年表对降水很敏感，反映了北美东部和北大西洋西部大尺度大气环流的异常。这项工作还将发展对厄尔尼诺/南方涛动（ENSO）异常敏感的南部大平原和墨西哥数百年的年表，ENSO是全球气候年际到年代际变化的最重要的已知原因。ENSO敏感年轮年表网络将在墨西哥和东南部扩展，以发展更长的ENSO重建，探索ENSO现象在小冰期的可能变化，并估计ENSO极端事件的频率，如1982-83年的温暖事件。还将在东非探索树木气候学的潜力，在那里已经发现了ENSO对气候的影响，但目前没有长期的年度气候代用指标。提出的研究将提供独特的古气候数据，这将有助于确定气候的自然变率，并可能有助于评估全新世晚期全球变暖和变冷时期的gcm气候模拟。

This award supports the development of an array of millennium- long tree-ring chronologies for the southeastern USA. These long chronologies are sensitive to precipitation, and reflect anomalies in large-scale atmospheric circulation over eastern North American and the western North Atlantic. This work will also develop centuries-long chronologies in the southern Great Plains and Mexico which are sensitive to anomalies in the EL Nino/Southern Oscillation (ENSO), the most important known cause of interannual to decadal variation in global climate. The network of ENSO- sensitive tree-ring chronologies will be expanded in Mexico and the Southeast in order to develop longer ENSO reconstructions, to explore possible changes in the ENSO phenomenon during the Little Ice Age, and to estimate the frequency of ENSO extremes such as the 1982-83 warm event. The potential for dendroclimatology will also be explored in East Africa, where and ENSO influence on climate has been detected, but where long, annual climate proxies are not presently available. The proposed research will provide unique paleoclimatic data that will help define the natural variability of climate, and may help evaluate GCM-simulations of climate during global warm and cool episodes of the late Holocene.