The Jason-1 Project should be ready to start distributing GDRs approximately 30 days after the end of Cycle 46. The distribution of GDR products from cycle 46 onwards is based on the same data product latency as for TOPEX/POSEIDON (approximately 30 days after the end of the cycle). Reprocessed GDR products for cycles 1 to 45 will gradually be made available once they have been processed and validated. The expected completion date for reprocessed GDR cycles is September 2003.

The first Jason-1 cycle began January 15, 2002 and corresponds to T/P cycle 344. Here is a list of all T/P cycle start times: http://oceanesip.jpl.nasa.gov/sealevel/TopexCycleTimes.txt

The orbit accuracy for the Jason IGDR is approximately 3 cm, which is comparable to the orbit accuracy for the Topex GDR.

The following fields have new algorithms in the Jason-1 Science Data Products:

The Topex/Poseidon and Jason-1 orbits also differ.

To form a compatible data set with Topex/Poseidon GDRs or MGDRs, it is recommended to use the Topex GDR Correction Product (GCP) developed by Phil Callahan. For more information contact jason@podaac.jpl.nasa.gov

The GDR is identical to the IGDR except for the following points: a more precise orbit is used, improved pole location data are used, and DORIS TEC grids are used. These differences affect the following parameters:

The following is a condensed version of the Topex/Poseidon Satellite Attitude Event Information and contains the start and stop times of the yaw state.

The following is the complete Jason-1 Satellite Attitude Event Information.