Offshore Radiation Observations for Climate Research at the CERES Ocean Validation Experiment

T he National Aeronautics and Space Administration’s (NASA’s) Clouds and the Earth’s Radiant Energy System (CERES) project is observing the radiant energy leaving the Earth’s atmosphere. CERES produces an archive of the radiation budget, from the bottom to the top of the atmosphere, with high temporal and spatial resolution for multiple years, with an accuracy necessary for climate change research (Wielicki et al. 1996). One expected payoff from analyzing this archive will be a new level of understanding of how clouds and aerosols affect the planet’s energy budget. Climate theory indicates that the veracity of a climate model hinges strongly on the accuracy of the radiation budget simulated by the model. CERES data are a key test bed for such models. To fill the test bed with quality data, much is required. The parameters needed to fill the CERES archive, such as irradiances at various altitudes within the atmosphere’s column, are not directly measured by the CERES instruments that are presently circling the planet on several of NASA’s Earth Observing System (EOS) satellites [Tropical Rainfall Measuring Mission (TRMM), Terra, and Aqua]. “Retrieval algorithms” that use the CERES measurements, ancillary data, and radiative transfer theory are required for this processing. These algorithms deal OFFSHORE RADIATION OBSERVATIONS FOR CLIMATE RESEARCH AT THE CERES OCEAN VALIDATION EXPERIMENT A New “Laboratory” for Retrieval Algorithm Testing