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Clouds and the Earth's Radiant Energy System (CERES) is NASA climatological experiment from Earth orbit. The CERES are scientific satellite instruments, part of the NASA's Earth Observing System (EOS), designed to measure both solar-reflected and Earth-emitted radiation from the top of the atmosphere (TOA) to the Earth's surface. Cloud properties are determined using simultaneous measurements by other EOS instruments such as the Moderate Resolution Imaging Spectroradiometer (MODIS). Results from the CERES and other NASA missions, such as the Earth Radiation Budget Experiment (ERBE), could lead to a better understanding of the role of clouds and the energy cycle in global climate change. ==Scientific goals== CERES experiment has four main objectives: * Continuation of the ERBE record of radiative fluxes at the top of the atmosphere (TOA) for climate change analysis. * Doubling the accuracy of estimates of radiative fluxes at TOA and the Earth's surface. * Provide the first long-term global estimates of the radiative fluxes within the Earth's atmosphere. * Provide cloud property estimates that are consistent with the radiative fluxes from surface to TOA. Each CERES instrument is a radiometer which has three channels - a shortwave channel to measure reflected sunlight in 0.3 - 5 µm region, a channel to measure Earth-emitted thermal radiation in the 8-12 µm "window" region, and a total channel to measure entire spectrum of outgoing Earth's radiation. The CERES instrument was based on the successful Earth Radiation Budget Experiment which used three satellites to provide global energy budget measurements from 1984 to 1993.〔NASA, (Clouds and the Earth's Radiant Energy System (CERES) ) (accessed Sept. 9, 2014)〕 CERES spatial resolution at nadir view (equivalent diameter of the footprint) is 10 km for CERES on TRMM, and 20 km for CERES on Terra and Aqua satellites. Onboard calibration sources for channels measuring reflected sunlight include solar diffusers and tungsten lamps. A pair of blackbody cavities that can be controlled at different temperatures are used for the Total and WN channels. Cold space observations and internal calibration are performed during normal Earth scans. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Clouds and the Earth's Radiant Energy System」の詳細全文を読む スポンサード リンク
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