The GEOstationary Coastal and Air Pollution Events (GEO-CAPE) mission was recommended by the NRC's Earth Science Decadal Survey to measure tropospheric trace gases and aerosols and coastal ocean phytoplankton, water quality and biogeochemistry from geostationary orbit, providing multiple daily observations within the field of view. Multiple observations per day are required to explore the physical, chemical, and dynamical processes that determine tropospheric composition and air quality over spatial scales ranging from urban to continental, and over temporal scales ranging from diurnal to seasonal. Likewise, high frequency satellite observations are critical to studying and quantifying biological, chemical, and physical processes within the coastal ocean and beyond. The GEO-CAPE Mission Study Team met 2009-2018. The study was completed in September 2018 as NASA transitioned to implementation of the second Earth Science Decadal Survey.