Tree-Ring Analysis of Regional to Large-Scale Paleoclimate

该奖项支持为美国东南部开发一系列长达千年的树轮年表。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范围大气环流的异常。这项工作还将在大平原南部和墨西哥建立数百年的年表，这些年表对厄尔尼诺/南方涛动(ENSO)的异常很敏感，ENSO是全球气候年际至年代际变化的最重要已知原因。将在墨西哥和东南部扩大对ENSO敏感的树轮年表网络，以发展更长的ENSO重建，探索小冰期ENSO现象的可能变化，并估计ENSO极端事件(如1982-83年暖事件)的频率。还将在东非探索树状气候学的潜力，在那里已经检测到气候和ENSO对气候的影响，但目前没有长期的年度气候指标。这项拟议的研究将提供独特的古气候数据，有助于定义气候的自然变异性，并可能有助于评估GCM-对全新世晚期全球变暖和变冷时期气候的模拟。

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.