CoAuthors

Giuseppe Foti (National Oceanography Centre, UK); Jens Wickert (Helmholtz Centre Potsdam GFZ, Germany); Martin Unwin (Surrey Satellite Technology Ltd, UK)

GNSS-Reflectometry uses surface-reflected signals of opportunity from Global Navigation Satellite Systems (such as GPS) to deliver additional Earth Observation capability with the potential for high-density sampling in space and time. Based on the principle of off-nadir bistatic forward scattering, the signals, processing and validation methods have much in common with conventional and SAR altimetry. The GEROS-ISS mission, recently selected by ESA for deployment on the International Space Station, has as primary mission objective to demonstrate the ability to deliver sea surface height estimates that help map the complex mesoscale structure (10-100km or longer) of the ocean. The secondary objective of GEROS-ISS is to monitor ocean surface roughness, particularly to improve the sampling of rapidly evolving winds in the vicinity of energetic atmospheric systems such as tropical cyclones. The latter is the primary mission objective of the NASA CYGNSS mission, due for launch in late 2016. The UK TechDemoSat-1 satellite, due for launch in late June 2014, will carry a GNSS-R receiver similar to the CYGNSS payload, and should provide new evidence of the observational capability of GNSS-R for ocean surface roughness and wind speed mapping.