GRACE Radio Occultation Data
Beside the precise determination of the Earth’s gravity field and it’s time variability the GRACE mission also enables the vertical sounding of the Earth's ionosphere and neutral atmosphere due to the radio occultation (RO) technique.
About 150-200 globally distributed profiles of bending angle, refractivity, and dry temperature per day are available since April 2002. The data are processed in near-real time (NRT) and delivered to weather service centers. In addition post-processed data are provided for the world-wide scientific community.
The GRACE RO data contribute to a global dataset built up of several RO missions operated by different institutions. Beside GRACE GFZ currently also processes RO data from the TerraSAR-X and Tandem-X missions. An overview about the current NRT status of all RO missions processed at GFZ can be found here.
The post-processed GRACE and other GFZ RO data are available as daily tar files containing the single profiles in netCDF format. The variables and data are self-explaining. The RO data are available here: CHAMP, GRACE-A, GRACE-B, TerraSAR-X, Tandem-X.
Further RO data (COSMIC, Metop, SAC-C) are provided by UCAR.
Remark#1: For the GRACE satellites the name GRACE-A is equivalent to GRACE-1 and GRACE-B is equivalent to GRACE-2. Both nomenclatures are in use.
Remark#2: Since 2014 the RO experiment changed temporary between GRACE-A and GRACE-B.