USGG2009

Last update 2009/09/28

USGG2009 is a refined gravimetric model of the geoid
in the United States and other territories,
which supersedes the previous models
USGG2003 and G99SSS.

For USGG2009 in CONUS regions, heights range
from a low of -52.53 meters (magenta) in the Atlantic Ocean
to a high of 3.47 meters (red) in the Labrador Strait.

USGG2009 refers to a NAD83 ellipsoid,
centered in the ITRF00 reference frame, and is the
best geopotential surface that approximates Mean Sea Level (MSL).

USGG2009 is NOT for converting between NAD83 and NAVD88.
USGG2009 is suitable for use with WGS84 and scientific applications.

For reference only, model USGG2009BETA is available

Data
• Interactive USGG2009 computations
• Download USGG2009 Files

Information
• The Official NGS GEOID Page
• Readme file for USGG2009
• Technical details
• Geophysics of the Geoid
• On-Line Papers
• The Geoid Research Page
• Acknowledgements
• FAQ

Related Pages
• GEOID09
• GEOID03
• USGG2003
• DEFLEC09
• GPS/bench mark data set for GEOID09

Have a geoid question?
• Contact the Geoid Team