Dissertation Research: High-resolution Reconstruction of Recent and Late-Holocene Climate Change in Equatorial East Africa

9320324赖特晚第四纪沉积物记录从气候敏感，封闭的盆地湖泊在热带东非是证明气候历史的复杂性，从千年到年的时间尺度。高分辨率重建非洲大陆的古气候的基本历史是复杂的个人主义的湖泊短期气候变化的反应，因为在间接的气候影响，湖泊水位和盐度的变化。本论文的研究将提高复杂沉积记录的高分辨率解释，通过（1）在四个相互连接的湖泊盆地系统中对近期气候引起的环境变化进行详细的古湖沼学研究，（2）调查这些浅水湖泊生态系统中湖泊无脊椎动物群落的生态敏感性和物种更替模式，（3）建立湖泊无脊椎动物化石组合分析作为高分辨率古气候重建的工具。从本论文的研究结果将被应用到一个强烈的争议，但缺乏记录的事件在东非和其他热带地区的气候历史的高分辨率重建：最后的千年，其中可能包括热带相当于中世纪温暖期和小冰期。我们对小空间尺度气候变化模型的了解，大部分来自于这样的古湖沼学研究。增加气候重建的时间分辨率的尝试对于在自然的短期气候变化的背景下理解和预测未来的气候变化模式将是非常宝贵的。***

9320324 Wright Late-Quaternary sediment records from climate sensitive, closed basin lakes in tropical East Africa are testimony to the complexity of climate history at time scales ranging from millennia to years. High resolution reconstruction of the underlying history of African continental paleoclimates is complicated by individualistic response of the lakes to short-term climate change because of variation in indirect climate effects, lake levels, and salinity. This dissertation research will improve high resolution interpretation of complex sedimentary records by (1) conducting a detailed paleolimnological study of recent climate-caused environmental change in a system of four interconnected lake basins, (2) investigating the ecological sensitivity and patterns of species replacement in the lacustrine invertebrate communities of these shallow lake ecosystems, and (3) establishing the analysis of fossil assemblages of these lacustrine invertebrates as a tool in high resolution paleoclimate reconstruction. %%% Results from this dissertation research will be applied to the high resolution reconstruction of a strongly debated but poorly documented episode in climatic history of east Africa and other tropical regions: the last millennium which may include tropical equivalents of the Midieval Warm Epoch and the Little Ice Age. Much of what we know about climate change modeling at small spatial scales derives from paleolimnological studies such as this. The attempts to increase the temporal resolution of climate reconstruction will be invaluable for understanding and predicting future patterns of climate change within the the context of natural, short-term climatic variation. ***