COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) is a joint US-Taiwan six-satellite constellation mission that is making use of radio signals from the Global Positioning System (GPS) to sound the Earth?s atmosphere via a technique called GPS radio occultation (RO). Since its launch in April 2006, COSMIC has been providing highly accurate globally distributed measurements of temperature and moisture from the Earth?s surface to over 30 km altitude for use in operational weather forecasting and climate research applications. COSMIC also provides measurements of electron density in the ionosphere above 100 km altitude to help scientists understand space weather science. Figure 1 shows the distribution of COSMIC soundings (in green) around the globe for a one day period along with current weather balloon station locations (in red). Under this award, the University Corporation for Atmospheric Research (UCAR) designed the COSMIC mission and has been serving as program manager on behalf of NSF and U.S. agencies to execute the mission. UCAR has also supported other RO missions of opportunity, as well as the COSMIC-2 mission, reach their full scientific and operational potential by supporting the development of these missions.

The main outcomes of this project have been the development of the UCAR COSMIC Data Analysis and Archive Center (CDAAC), the operation of the CDAAC to process and distribute nearly 15 Million (~7 Million from COSMIC) RO data products to the operational and research science communities, more than 550 scientific peer-reviewed publications related to COSMIC and radio occultation as noted by Web of Science (Aug 11, 2019), support for the procurement and installation of COSMIC-2 tracking stations and ground GNSS receivers, provision of necessary systems engineering, integration and test engineering, and program management support to facilitate execution of the COSMIC-2 mission, and technical and educational support for early career scientists and data users to increase the scientific capacity in the field of GNSS RO.

UCAR has developed a fully automated state-of-the-art RO data processing, distribution, and archival system. The CDAAC hardware, software, and science data processing algorithms have been developed with over 100 person-years of scientific and engineering effort and currently provide high quality GPS RO data to the science community. The CDAAC data products have been extensively validated in peer-reviewed publications via comparisons with data from other instruments, numerical weather prediction and space weather models, as well as data from other data processing centers. Figure 2 shows the number of COSMIC atmospheric profiles generated per day throughout the mission with a total of approximately 7 million profiles. UCAR makes all processed RO data available with a powerful website at www.cosmic.ucar.edu. Although the COSMIC mission is scheduled to be de-commissioned in May 2020, COSMIC-2 was launched in June 2019 and is producing the highest quality RO ever recorded which will benefit the community for years to come.

COSMIC data have been used in over 550 scientific publications that have demonstrated significant impact on operational weather prediction, climate monitoring, and space weather and ionospheric research. For example, major global weather prediction centers, including NOAA?s National Center for Environmental Prediction (NCEP) and the European Centre for Medium-range Weather Forecasting (ECMWF) are providing significantly improved weather forecasts by assimilating near real-time COSMIC data. RO data are also a powerful observational tool to monitor the Earth?s climate due to their high accuracy and stability over time. COSMIC and other RO datasets are already being used to investigate temperature trends in the troposphere and stratosphere, and with continued RO datasets going forward such as COSMIC-2, similar future studies will be able to provide temperature trends of the Earth?s atmosphere with high confidence. COSMIC data are also being used by scientists to better understand ionospheric processes and better predict space weather, which will lead to future societal benefits for navigation, communication, and electrical power grid applications.

To maximize the scientific benefit of COSMIC data to society, the UCAR COSMIC Program has supported development and educational efforts to increase capacity in RO science and technology. There are now over 5000 registered COSMIC data users from over 100 countries, representing major U.S. and international universities, leading operational weather centers, research laboratories, and several private companies. UCAR has organized annual data user workshops since the start of the program to provide these users with technical and scientific support and a forum to present, discuss, and learn about new advances in RO technology and scientific applications. UCAR has also provided scientific and computer mentoring of under-graduate and graduate students, post-docs, and culturally diverse under-graduate students in the UCAR/SOARS (Significant Opportunities in Atmospheric Research and Science) program. Finally, UCAR has disseminated the CDAAC software to universities to further education of young researchers in RO technology and scientific applications.

Last Modified: 04/30/2020
Modified by: William S Schreiner