Advised by: Dr. Wiles
Abstract: Reconstructing and understanding historical lake levels provides information about how climate influences lake level fluctuations, which is important for managing Lake Michigan- Huron’s (MH) coasts. This study reconstructs historical MH lake levels using ten ring-width chronologies from Southeast Alaska, which are significantly correlated at the 0.01 confidence level with January – June average MH lake levels. Tree ring chronologies from Southeast Alaska can be used to create a model of MH because of atmospheric teleconnections, like the Pacific North American Pattern (PNA), which produce similar atmospheric pressure anomalies across both regions. The model explains 33.8% of the variance in MH lake levels (January – June), and the validity of the model was tested through a series of calibration and verification statistics, confirming a well-verified stable relationship through time.
Findings indicate that MH lake level fluctuations are primarily based on large-scale atmospheric climate patterns that may be altered by human activity, volcanic eruptions, or strong climate events. Reconstructed high lake levels are attributed to volcanic activity in the 1690s, 1673, 1755, and 1809 and a strong El Niño event from 1876 to 1878, whereas lows are attributed to droughts, corresponding with the conditions of the 1930s Dust Bowl.
