Ground Segment

The ground segment is a distributed system that uses resources from NASA, CNES, EUMETSAT and NOAA. Its operation and relationship with other elements in the JASON-3 mission are presented in the diagram below.

In accordance with the 4-partner agreement for the Jason-3 project:

• raw altimetry data from POSEIDON-3BB, DORIS and the radiometer will be processed by the NOAA and EUMETSAT centres to produce near-real time altimetry products (OGDR: Operational Geophysical Data Record);

• raw altimetry data from POSEIDON3BB and the radiometer will only be processed by the CNES mission centre to produce delayed time altimetry products (GDR: Geophysical Data Record, IGDR, S-IGDR and S-GDR);

• production of preliminary and precise orbit missions for the satellite is undertaken by CNES, using data from the DORIS system, supplemented, for precise orbits, by data from the GPS system (ground data and GPSP) and from the laser system;

• near real time altimetry products (OGDR) are distributed by the NOAA and EUMETSAT centres. They are archived by the NOAA, EUMETSAT and CNES centres;

• delayed time altimetric products are archived and distributed by the NOAA and CNES centres;

• all housekeeping and scientific telemetry and all auxiliary data are archived by the NOAA and CNES centres, whatever the data source;

• added-value products from the DUACS system (Data Unification and Altimeter Combination System) generated by CNES are archived and distributed under CNES responsibility.