GPS-based Operational Geophysical Data Record (GPS-OGDR-SSHA) for Jason-3
-------------------------------------------------------------------------

Date: October 3, 2016

The Jason-3 GPS-OGDR-SSHA product is identical to the official OGDR-SSHA
product generated and distributed by NOAA and EUMETSAT, except that it contains
two additional fields in the NetCDF file:
1) gps_alt  - GPS-based orbit altitude of the satellite.
2) gps_ssha - Sea surface height anomaly derived by using the GPS-based orbit
   altitude (gps_alt) instead of the DORIS-DIODE based orbit altitude (alt).
   e.g. ssha-alt+gps_alt

The GPS-OGDR-SSHA product is available with a typical latency of 4 hours from
the last available measurement on each data file, and the GPS-based orbit
altitude has accuracies of < 1.5 cm (RMS).

The GPS-OGDR-SSHA product is available via ftp at the Physical Oceanography
Distributed Active Archive Center (PO.DAAC):
ftp://podaac.jpl.nasa.gov/SeaSurfaceTopography/jason3/preview/L2/GPS-OGDR/

Note that the Jason-3 GPS-OGDR-SSHA product is a research-grade product that is
generated on a best efforts basis by the Orbiter and Radio Metric Systems
group at JPL. 

Please refer questions or comments to:
Shailen Desai (Shailen.Desai@jpl.nasa.gov)