Late Holocene Geo-biologic Records of Climate Changes at Lake Tanganyika, East Africa, with Seasonal to Decadal Resolution

这一本科院校研究奖将帮助从东非坦噶尼喀湖北部盆地代表过去3000年历史的一系列沉积物岩芯中建立生物和地球化学记录。研究目标是产生高分辨率的精确年代的古气候记录，以检验最近提出的利用小冰期期间的太阳变率对热带间辐合带进行赤道向对称压缩的模型的有效性，并调查太阳强迫对热带降雨的其他可能影响。这位研究人员推测，当从该湖开发出详细的地质生物时间序列时，将有助于确定坦噶尼喀湖离散的古气候事件，这些事件可以与热带纬度的记录进行比较，以提供从3000年到现代的干旱和降雨趋势的记录。部分研究工作将涉及基于硅藻的过去风活动的替代。这些数据为深入了解亚非古季风系统中晚全新世变异性的性质和起源提供了一个潜在的新来源，到目前为止，几乎只通过位于阿拉伯海及其周围的地点进行了研究。这一研究项目的结果将与从热带到极地纬度的其他记录进行比较，从而将坦噶尼加盆地的气候历史置于全球范围内。确定近期生产率下降的历史--通常被归因于全球变暖--将为了解它们的来源提供重要的见解。该奖项将支持几名本科生帮助分析沉积物记录，与非美国科学家的国际合作将增加全球对研究数据的获取和对其解释的想法分享。

This Research in Undergraduate Institutions (RUI) award will help develop biological and geochemical records from a series of sediment cores representing the last 3,000 years of history from the northern basin of Lake Tanganyika, East Africa. The research goal is to produce high-resolution precisely dated paleoclimate records to test the validity of a recently proposed model of symmetric, equator ward compression of the Inter Tropical Convergence Zone by solar variability during the Little Ice Age, and to investigate other possible effects of solar forcing on tropical rainfall. The researcher postulates that detailed geo-biologic time series, when developed from the Lake, will help define discrete paleoclimate events at Lake Tanganyika that could be compared with records from tropical latitudes to provide a record of drought and rainfall trends from 3,000 years through modern times.Part of the research effort will involve diatom-based proxies of past wind activity. These data represents a potential new source of insights into the nature and origin of late Holocene variability in the Afro-Asian paleo-monsoon system, which until now has been studied almost exclusively through sites located in and around the Arabian Sea. Results from this research project will be compared to other records ranging from tropical to polar latitudes thereby placing the climatic history of the Tanganyika basin into a global context. Determining the history of recent productivity declines, often attributed to global warming, will provide important insights into their origin.The award will support several undergraduate students to help analyze the sediment records and the international collaborations with non-US scientists will increase worldwide access to the research data and a sharing of ideas regarding its interpretation.