CER_GEO_Ed4_GOE12_SH_V01 is the Satellite Cloud and Radiation Property retrieval System (SatCORPS) Clouds and the Earth's Radiant Energy System (CERES) Geostationary Satellite (GEO) Edition 4 Geostationary Operational Environmental Satellite 12 (GOES-12) over the Southern Hemisphere (SH) Version 1.0 data product. Data was collected using the GOES-12 Imager on the GOES-12 Platform. Data collection for this product is complete.This data set comprises cloud micro-physical and radiation properties derived hourly from GOES-12 geostationary satellite imager data using the Langley Research Center (LARC) SATCORPS algorithms supporting the CERES project. Each active geostationary satellite's cloud micro-physical and radiation properties are merged to create hourly global cloud properties that estimate fluxes between CERES instrument measurements to account for the changing diurnal cycle. The data set is arranged as files for each hour and in netCDF-4 format. The observations are at 4 km resolution (at nadir) and are sub-sampled to 8 km.CERES is a key Earth Observing System (EOS) program component. The CERES instruments provide radiometric measurements of the Earth's atmosphere from three broadband channels. The CERES missions follow the successful Earth Radiation Budget Experiment (ERBE) mission. The first CERES instrument, the protoflight model (PFM), was launched on November 27, 1997, as part of the Tropical Rainfall Measuring Mission (TRMM). Two CERES instruments (FM1 and FM2) were launched into polar orbit on board the Earth Observing System (EOS) flagship Terra on December 18, 1999. Two additional CERES instruments (FM3 and FM4) were launched on board Earth Observing System (EOS) Aqua on May 4, 2002. The CERES FM5 instrument was launched on board the Suomi National Polar-orbiting Partnership (NPP) satellite on October 28, 2011. The newest CERES instrument (FM6) was launched on board the Joint Polar-Orbiting Satellite System 1 (JPSS-1) satellite, now called NOAA-20, on November 18, 2017.