Shoreline change data were digitized in house for the 1966-shoreline using US Coast and Geodetic Survey charts. The 2002/2003 shoreline was derived from NOAA's Biogeography Program shoreline file for Guam.
1) NGDC ETOPO2 Global 2' Elevations
2) Digital Elevation models produced by NOAA's Biogeography Program
3) U.S. Army Engineer Joint Airborne Lidar Bathymetry Technical Center of Expertise
(JALBCTX)