NOAA: Commercial Companies Can Effectively Provide Radio Occultation Data
In its Commercial Weather Data Pilot (CWDP) Round 2, the National Oceanic and Atmospheric Administration (NOAA) evaluated GNSS radio occultation data from two U.S. commercial space companies: GeoOptics and Spire. NOAA concludes that, based on the results of CWDP Round 2, the commercial sector is able to provide radio occultation data that can support NOAA’s operational products and services.
(The) report demonstrates, commercial satellite data will enable NOAA to make significant improvements in forecasting worldwide within the consistent budget limitations under which it operates.
Conrad Lautenbacher - GeoOptics CEO
Radio Occultation (RO) is an established method for remote sounding of the atmosphere. The technique uses an instrument in low-Earth orbit to track radio signals from Global Navigation Satellite System (GNSS) transmitters as they rise or set through the atmosphere. The occulting atmosphere refracts or bends the radio signals, and given the precise positions of both satellites, the bending angle can be deduced from the time delay of the signal. Collecting these measurements for a full occultation through the atmosphere provides a vertical profile of bending angles, from which profiles of physical quantities such as temperature, humidity, and ionospheric electron density can be retrieved. These data primarily feed numerical weather prediction (NWP) models that support weather forecasts, and also support space weather applications.
Deployable on small satellites, RO instruments complement microwave and infrared sensors, fill in the sparse geographical and temporal coverage of radiosondes, and provide vertical and temporal resolution complementing other satellite observations. Weather centers currently ingest thousands of RO profiles per day from various government satellite systems. Studies indicate that increasing the quantity of RO data, particularly in orbits and times not served by government systems, would further improve forecasts. Ionospheric observations from RO sensors also enhance space weather situational awareness, revealing variations in the ionosphere that impact GNSS performance and radio communications. Beyond these direct benefits, additional sources of RO data could provide risk mitigation for any unexpected reductions in other data streams.
“(The) report demonstrates, commercial satellite data will enable NOAA to make significant improvements in forecasting worldwide within the consistent budget limitations under which it operates,” said GeoOptics CEO Conrad Lautenbacher.