Sea Ice Altimetry and Classification using Grazing Angle Reflected GNSS Signals Measured by Spire’s Nanosatellite Constellation

Abstract:

Spire Global, Inc. is a leading player in the nanosatellite sector, and the first to provide commercial, low-cost GNSS-radio occultation measurements to support critical weather data for numerical weather prediction.

Since early-2019, the Spire satellite constellation has been continuously collecting GNSS signals reflected over sea ice at low grazing angles. The reflected signals at these grazing angles are phase-coherent at L-band frequencies and thus offer the potential for extracting sea ice properties such as altimetric height, extent and age. In this presentation, we review the collection and retrieval of sea ice properties using Spire satellite measurements. Altimetric estimates exhibiting several centimeter precision over sea ice are highlighted and discussed. Initial results demonstrating the feasibility of mapping polar ice extent and type using phase coherent GNSS signals are also presented. Finally, we discuss our plans to scale up the production of these measurements to help meet the need for resolving mesoscale processes in the cryosphere.