CYGNSS Surface Heat Flux Product: Development, Results, and Updates

Latent (LHF) and sensible (SHF) heat fluxes over the world’s oceans play a critical role in the genesis and evolution of various weather phenomena and climate patterns. While in-situ ocean surface observations of surface heat fluxes are the standard, these data are often limited in their temporal and spatial resolution. Although surface heat fluxes estimated from polar orbiting satellites can provide greater coverage, they often feature coarse spatial and temporal resolution, especially in the lower latitudes. The NASA CYGNSS (Cyclone Global Navigation Satellite System) constellation of eight small satellites provides estimates of surface wind speed over the tropical and subtropical oceans, providing a higher temporal and spatial resolution over these parts of the globe. Since CYGNSS utilizes the GPS L1 channel, its signal is less sensitive to heavy precipitation. Combining CYGNSS winds with thermodynamic variables from another source (e.g. MERRA-2), we have developed and released the CYGNSS Surface Heat Flux Product, providing LHF and SHF estimates for the entire CYGNSS mission (March 18, 2017-present). This product, validated with buoy data, has been developed and distributed in order to aid the scientific community’s understanding of air-sea interaction and their role in various weather events, such as tropical and extratropical cyclones, tropical convection, and large-scale weather patterns (e.g. MJO).