Skip to Main Content

Eolian sand deposited in lakes downwind of coastal sand dunes can record a history of paleoclimatic fluctuations. The eolian sand signals from sediment within the Grand Mere Lakes, Michigan, which are downwind of sand dunes along southeastern coastal Lake Michigan, record the same sunspot, climate history, and lake-level fluctuations observed elsewhere along the east-central Lake Michigan coastline. Sediment cores were extracted from the Grand Mere Lakes in Berrien County, Michigan, and analyzed for variations in weight percentage of sand with depth, the sand signal, at 1 cm sampling intervals. Radiocarbon dates obtained from terrestrial macrofossils within the cores were used to develop age-depth models, from which sedimentation rates were derived, both for the varying sedimentary facies and the entire core. Spectral analyses of the sand signal data using both multi-taper and REDFIT methods indicate multiple periodicities that correspond to those from other regional and global studies, including Lake Michigan lake-level fluctuations, Lake Michigan coastal dune formation, and solar cycles. The common periodicities between the Grand Mere Lakes sand data and other studies suggest the sand-signal data set is not random, and is best explained as a record of paleo dune mobility. The appearance of the 80–110 year Gleissberg solar cycle in the data suggests that the storminess recorded by the eolian sand was influenced by periodic variability in extratropical cyclones across the Lake Michigan basin which, in turn, reflects variability in circulation patterns driven by the North Atlantic Oscillation, the variability of which has been associated with solar cycles.

You do not currently have access to this chapter.

Figures & Tables

Contents

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal