Figure 13C. Relative Coastal Change-potential for Sleeping Bear Dunes National Lakeshore. The colored shoreline represents the relative coastal change-potential index (CPI) determined from the six variables. The very high change-potential shoreline is located along sandy stretches of coast where regional coastal slope change-potential is high. The low change-potential shoreline is located along bluffs where coastal slope is steeper and wave heights are generally low.