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. <br/><br/>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.
Reconstructing Holocene Climate Variability from Varved Lake Sediments in the North American Mid-Continent