GNSSROAP

GNSS RO Atmospheric Profiling at NSA C1

15 April 2017 - 14 April 2025

Lead Scientist: Martin Stuefer

Observatory: NSA

Electromagnetic waves radiated from GNSS (Global Navigation Satellite System) satellites are refracted along their transmission through the Earth’s atmosphere. The GNSS Radio Occultation (RO) technique depicts the magnitude of the refraction (or bending) of the electromagnetic radiation, which depends on the vertical structure of the atmosphere. In recent years RO data have gained high importance through their application in meteorology to derive atmospheric profiles of temperature, pressure and water vapor. RO data are available globally; the technique is permanent, weather-independent and calibration-free. Atmospheric GNSS products are assimilated in operational near-real time regional and global weather prediction models, and have contributed significantly to improve our understanding of the current state of the atmosphere. The GFZ German Research Centre for Geosciences in Potsdam maintains a global GNSS network of about 30 ground stations for precise satellite clock & orbit determination, radio occultation measurements and crustal dynamics studies. The ground-based GPS data are analyzed at the GFZ in near-real time. Recently the GFZ offered to expand their GNSS network to Alaska to the ARM ARM NSA C1 site of Utqiaġvik (Barrow). A GFZ ground station will be established this year in early summer. Precise vertical atmospheric RO sounding data of temperature and water vapor from ARM NSA will be processed at the GFZ in near-real time; the data will be made available via the ARM Data Management Facility (DMF).