Cloud, Atmospheric Radiation and Renewal Energy Application (CARE) shortwave cloud radiative forcing from Himawari-8 and FY-4A Husi Letu
Key Laboratory of Remote Sensing and Digital Earth, Aerospace Information Research Institute, Chinese Academy of Sciences. Beijing 100101, China
Abstract
Cloud shortwave radiation forcing (SWRF) with high spatial-temporal resolutions and precision are essential for Earth^s land surface or top-of-atmosphere (TOA) radiation budget calculations. The cloud optical thickness (COT) and cloud effective radius (CER) are critical input parameters for accurately estimating SWRF. In this study, we proposed a COT and CER algorithm that suitable for water and ice clouds from the new-generation geostationary satellite Himawari-8 and FY-4A measurements, based on the radiative transfer theory and optimal method. Based on the retrieved COT and CER, a method for estimation of cloud SWRF at the surface and TOA was proposed based on the look-up-table (calculated by the radiative transfer model - RSTAT) method. Validation of SWRF with the CERES level-3 product, estimated SWRF at the surface and the TOA by this study show very good agreement, with R values of 0.97 and 0.98, root-mean-square-error values of 15.0 Wm-2 and 16.6 Wm-2. While, mean-bias-error values of -5.6 Wm-2 and -8.5 Wm-2 indict that our SWRF results have a slightly under-estimation. This research can provide important reference for the subsequent full radiation budget (shortwave plus longwave) estimation. Detailed products please see our homepage (http://www.slrss.cn/care_zh/).
Keywords: Cloud shortwave radiation forcing, cloud remote sensing, CARE
