High-Resolution Paleoclimatic Record of a Closed-Basin Lake in the Northern Great Plains

Fritz, Sherilyn C.明尼苏达大学该奖项支持将化石硅藻组合作为大平原北部封闭盆地湖泊月亮湖古水文/古气候指标的研究。本研究将尝试重建无效水分（降水减去蒸散）的变化。硅藻推断的盐度和气候之间的历史关系将用于计算有效水分和水文干旱的传递函数（帕尔默水文干旱指数），然后将其扩展到整个冰川后记录。气候条件将以整个全新世的世纪尺度和十年尺度在三个时期进行评估：末次冰期-消冰期、早全新世森林/草原过渡和过去2000年。来自气候敏感农业区的古气候记录，如大平原，对过去的气候知之甚少，已知的是粗糙的分辨率，将为了解当地、区域和全球尺度上的气候变化提供宝贵的贡献。通过分析古气候记录中的长期趋势来了解干旱特征，将为规划和管理可能伴随未来干旱事件的水资源短缺提供有价值的信息。

Abstract ATM-9414381 Fritz, Sherilyn C. University of Minnesota This award supports the study of fossil diatom assemblages as paleohydrological/paleoclimatic indicators in Moon Lake,a closed- basin lake in the northern Great Plains. This study will attempt to reconstruct changes ineffective moisture (precipitation minus evapotranspiration. The historical relationship between diatom- inferred salinity and climate will be used to calculate a transfer function for effective moisture and hydrological drought (Palmer Hydrological Drought Index) which will then be extended to the entire post-glacial record. Climatic conditions will be assessed at century-scale resolution through the entire Holocene and at decadal-scale resolution during three periods: the last glaciation- deglaciation period, the early-Holocene forest/prairie transition, and past 2000 years. Paleoclimatic records from climatically sensitive agricultural regions such as the Great Plains, where little is known of past climate, and what is known is of a coarse resolution, will provide a valuable contribution to the understanding of climatic variability on local, regional, and global scales. Understanding drought characteristics through the analysis of long-term trends in the paleoclimatic record will provide valuable information for planning and managing water shortages that may accompany future drought events.