(ESH) Effects of Glacial Lake Agassiz on the Climatic History of Minnesota

9508216莱特冰川湖阿加西是一个巨大的湖，面对着正在消退的劳伦蒂德冰盖。它位于明尼苏达州西北部的南部和东部臂在大约11,600到11,000年前被占领，但在经历了与年轻仙女座时期同时期的干旱时期后，只有南部臂被占领，从10,000到9,500放射性碳B.P.。这项建议旨在通过对小型深湖的各种沉积物的地层分析，评估18O光的冷冰川融水对邻近冰雹的气候、植被和小湖泊湖泊学顺风的影响。通过对介形虫的花粉、稳定同位素和微量元素组成的分析，有机质中纤维素的稳定同位素组成，介形虫组合的物种组成，以及VOLVE计数和AMS放射性碳测年，将建立一个与阿加西湖扩张和减少阶段相关联的年代地层。东臂下风的一个地点应该显示出一段湖泊效应，即阿加西湖对邻近景观气候的影响。

9508216 Wright Glacial Lake Agassiz was a huge lake fronting the retreating Laurentide ice sheet. Its southern and eastern arms in northwestern Minnesota were occupied from about 11,600 to 11,000 radiocarbon years ago, but following a dry period contemporaneous with Younger Dryas interval only the southern arm was occupied, from 10,000 to 9,500 radiocarbon B.P. This proposal aims to evaluate the effects of the cold glacial meltwaters of light 18O on the climate, vegetation, and small-lake limnology downwind on the adjacent moraines by stratigraphic analysis of varved sediments of small deep lakes. analysis of pollen, stable-isotope and trace-element composition of ostracodes, stable isotope composition of cellulose in organic matter, and species composition of ostracode assemblages will be used along with varve counts and AMS radiocarbon dates to establish a dated stratigraphy to correlate with Lake Agassiz phases of expansion and reduction. A site downwind of the eastern arm should show one interval of lake effects, of Lake Agassiz on the climate of the adjacent landscape.