Geosynchronous Continental Land-Atmosphere Sensing System (G-Class): Persistent Radar Imaging for Earth Science

More frequent imaging of Earth system processes is recognised as one of the emerging needs in Earth observation. Conventional low Earth orbit satellites are limited in their ability to provide this, whereas satellites in geosynchronous orbit can in principle provide continuous imaging. A new mission design has been developed from studies for a previous geosynchronous radar mission concept (GeoSTARe) to improve its technical feasibility and geographical coverage, and to reinforce its science focus. This new mission (Geosynchronous - Continental Land Atmosphere Sensing System (G-CLASS)) is presented. G-CLASS is in fact a family of missions: we present a version focussed on the diurnal water cycle - G-CLASS:H20 - for which geosynchronous radar has great potential. G-CLASS:H20 is being developed as a proposal for ESA's Earth Explorer programme.