Monitoring Earth's shortwave reflectance: LEO and GEO system architectures

Monitoring the Earth's shortwave reflectance with persistent, sub-diurnal, cloud-resolved sampling would improve understanding of key climate system processes and track geo-engineering efforts. Current measurement systems do not provide the spatial, spectral or temporal sampling to distinguish between natural variability and anthropogenic modification, so this paper presents Low Earth Orbit (LEO) and Geosynchronous Earth Orbit (GEO) system architectures that would provide these monitoring capabilities. The LEO system concept would be a constellation of sixteen microsatellites in four orbit planes with a miniature push-broom Dyson spectrometer providing a 709 km swath. The satellite would be a Boeing microsat that builds on heritage of recent Boeing Space Environmental NanoSat Experiment (SENSE) mission. The GEO system concept would be a scanning Offner spectrometer on a constellation of six satellites launched from a single EELV class launch vehicle. Both systems would provide a two hour revisit, globally, at 1 km spatial resolution and 10 nm spectral resolution between 380 nm and 2510 nm.