This study tested a new method of coastline change analysis to examine coastline change at four sites along the Lower Michigan coast. Shoreline position was manually delineated from aerial photography for multiple years between 1938 and 2010. The positional uncertainty associated with each shoreline was calculated in a GIS. A new method was developed to analyze the digitized shorelines. This new method generates a buffer (epsilon band) with radius equal to the positional uncertainty around each shoreline and uses these buffers to visualize and test for significant change. Significant change is determined by comparing a calculated proportion of similarity to a user-defined threshold. A series of transects perpendicular to the shoreline were then used to determine the direction and magnitude of change. Results indicate that shoreline position was most dynamic at the Manistee County site, and was least dynamic at the Sanilac County site. Overall there were more pairs of years with significant shoreline change at the two west coast sites, which suggests that shoreline position is more variable at the two sites along the west coast of Lower Michigan than along the east coast of Lower Michigan. The principle advantage of this dual epsilon method is that it analyzes change along the entire shoreline. This study demonstrates that the dual epsilon band method is feasible along a tideless coast.
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