Surface downward longwave radiation estimation from new generation geostationary satellite data

Surface downward longwave radiation (SDLR) is a key component of the Earth's energy budget. To use new-generation geostationary satellite data with high spatial and spectral resolution for SDLR estimation, we developed clear-sky algorithm based on multi-channel brightness temperature (BT) precipitable water vapor (PWV), named as MBTW, strictly clear conditions, atmospheric parameters (named NewAtmos) probably conditions. Then, framework to estimate all-sky SDLR; combined two algorithms an existing cloudy-sky algorithm. Finally, SDLRs were calculated using proposed FY-4A GOES-16 data. The validation results against field measurements indicated that MBTW NewAtmos performed well under expected had RMSEs 24.8 W/m2 18.3 data, which comparable those derived single parameters; former portrayed better consistency than latter. RMSE instantaneous method 24.6 20.1 they 23.7 hourly SDLR. from showed accuracy ERA5 at same resolution, also yielded more details variation atmospheric-parameter-based algorithm, because high-resolution thermal infrared (TIR) BT was used in our method. Furthermore, PWV, cloud liquid path ice produced very similar therefore, conditions missing parameters, can be alternative achieve continuous estimation.