TEMPORALLY CONSTRAINED AEOLIAN SAND SIGNALS AND THEIR RELATIONSHIP TO CLIMATE, OXBOW LAKE, SAUGATUCK, MICHIGAN

Interrelationships among late Holocene climate, the dynamics of coastal dunes and sedimentation in adjacent small lakes along coasts of the upper Great Lakes have been studied for over a decade. Nonetheless, many questions remain as to relationships between climate variability and dune activity. In this study wind, temperature, precipitation, drought, evaporation, and lake level are correlated individually with ²¹⁰Pb/¹³⁷Cs/⁷Be dated sand deposits from core samples taken in a small lake in the lee side of small dune ridges near Saugatuck, Michigan. Linear regressions were run to evaluate the strength of their relationship year-by-year, and at offsets of one to two years. Visual correlations were also attempted by evaluating the trends in the annual data sets. While year-by-year R² values were not strong, or mixed results made them inconclusive, visually examined trends showed more promising correlations. The strongest correlations exist among sand percent by weight, winter drought, and lake level. While small discrepancies among trends occur, results show a relationship among rising or high lake levels, wet conditions, and strong eolian activity (based on increased presence of sand in lake sediment). The implications of this research are that dune activity is linked to periods of wet conditions and storminess. Results can be used as a modern analogue for coastal dune activity during times of high lake level.