Constellation Observing System for Meteorology, Ionosphere, and Climate

Developing innovative Global Navigation Satellite Systems observational techniques for the Earth Science community

Our Program

The UCAR COSMIC Program has been a leader in the retrieval and scientific application of GNSS, e.g. GPS, data since UCAR led the GPS/MET GPS radio occultation (RO) mission in the mid 1990s. It contributed to the design, management, and operation of the FORMOSAT-3 / Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC-1) mission since 2006. The mission is still providing high-quality RO profiles that are having a significant positive impact on weather and space weather forecasting and research. The success of COSMIC has prompted U.S. agencies (led by NOAA) and Taiwan's National Space Organization to execute a COSMIC follow-on operational mission called FORMOSAT-7/COSMIC-2 (COSMIC-2) that has put six satellites with next generation GNSS RO payloads into low Earth orbit.


COSMIC-1 data are now available for download without registration. Details here.

Icon COSMIC's Summer 2020 Newsletter (3.0 MB) is posted.

COSMIC-2 neutral atmosphere and space weather data are available at CDAAC and TACC.

COSMIC-2 data are making important contributions to NOAA's weather forecast models this hurricane season.

COSMIC-2 satellite image courtesy of Surrey Satellite Technology Ltd.


COSMIC-2 satellite

Data Processing Center

Our data processing center uses ground- and space-based GNSS and in-situ sensor observations to generate higher level neutral atmospheric and ionospheric data products for a number of satellite missions in near real-time, post-processing, and reprocessing modes. The table shows current radio occultation profile counts by mission.


GNSS radio occultation illustration