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Elevation Data | Passive Data
Change Plots | Profile Comparisons

Change scale Change plot
Change - elevation differences between lidar surveys obtained in September 1997 and in September 1998, within one week of Hurricane Bonnie. The change data shows elevation losses (erosion) in yellows and reds, and elevation gains (accretion) in blues and purples. To calculate the change, the elevation of each data point in one survey is differenced from all data that occur within 1 m horizontal in the other survey.