GEOID99 is a refined model of the geoid in the United States, which supersedes the previous models GEOID90, GEOID93, and GEOID96.
For the conterminous United States (CONUS), GEOID99 heights
range from a low of -50.97 meters (magenta) in the Atlantic Ocean
to a high of 3.23 meters (red) in the Labrador Strait.
However, these geoid heights are only reliable
within CONUS due to the limited extents of the
data used to compute it.
GEOID99 models are also available for Alaska, Hawaii, and Puerto Rico & the U.S. Virgin Islands.
