Reconstructing Holocene Climate Variability from Varved Lake Sediments in the North American Mid-Continent

该奖项将支持对每年层状湖泊沉积物（varves）的研究，以提供过去12,000年美国大湖地区过去气候的详细记录。这种不同的沉积物记录可以证明是解决该地区干旱频率和气候突变问题的关键信息宝库。研究人员将利用现有的区域仪器记录的温度、降水量和主要大气环流模式，通过对单个湖泊沉积物的铅测年记录构建全新世气候变率的连续氧同位素时间序列，评估气候对氧同位素记录的控制作用。通过对离散的全新世气候事件的高分辨率氧同位素分析，研究人员将建立过去自然气候变化的特征和速率。

This award will support research on annually-laminated lake sediments (varves) to provide detailed records of past climate from the Great Lakes region of the United States over the past 12,000 years. Such varved sediment records can prove a treasure trove of information critical to addressing issues of drought frequency and abrupt climate change in the region. By constructing continuous oxygen isotope time series of Holocene climate variability for lead dated sediment records from individual lake sites, the investigators will evaluate climatic controls on oxygen isotope records with existing regional instrumental records of temperature, precipitation amount, and dominant atmospheric circulation patterns. By focusing on high-resolution oxygen isotope analyses across discrete Holocene climatic events, the researchers will establish the characteristic and rate of past natural climate variability.