Genesis GPS Occultation Observations Level 2 data contains vertical profiles of atmospheric temperature, pressure, refractivity, and water vapor pressure. Data is derived from radio occultation measurements by CHAMP and SAC-C low-earth-orbit satellites, with over 200 daily occultations per satellite. The dataset includes comparisons to NCEP and ECMWF weather analyses.
Use Cases
- Validate NCEP and ECMWF weather model temperature profiles against GPS occultation-derived temperature data.
- Analyze global water vapor pressure profiles to study humidity distribution in the troposphere.
- Monitor atmospheric refractivity profiles for climate detection studies, leveraging the self-calibrating property of the measurements.
- Compare pressure profiles from CHAMP and SAC-C satellites to assess instrument consistency.
- Compute geopotential heights and derived wind fields using independent height and pressure data from the profiles.
Strengths
- Sub-kilometer vertical resolution for detailed atmospheric profiling.
- Sub-Kelvin temperature accuracy below 45 km altitude.
- Over 200 daily occultations per satellite provide global coverage.
- Temperature profiles show mean consistency with NCEP/ECMWF models better than 0.5 K.
Limitations
- Profile coverage is limited between 60 km altitude and the middle troposphere.
- Specific row count, temporal range, and data volume are not provided.
- Water vapor density derivation requires independent temperature knowledge.
Provenance
- Source
- NASA Earthdata, from SCIOPS organization, using JPL Blackjack GPS receivers on CHAMP and SAC-C satellites.
- Collection Method
- Derived from LEO-GPS radio occultation (limb sounding) data, with inversion of atmospheric phase delay measurements.
- Time Range
- null
- Freshness
- null
- Geography
- Global coverage from satellite occultations.