The Improvement of COMS-based Outgoing Longwave Radiation Retrieval and Validation Method

Abstract:

Outgoing Longwave Radiation(OLR) is emitted thermal energy from the top-of-atmosphere(TOA) of the earth into space whose spatial and temporal variability has significant impacts on the climatic and meteorological changes. The only direct observation of TOA OLR is from broadband satellites. Unlike them, geostationary satellites have advantages on obtaining instantaneous and periodical observations from the same location. However, narrowband satellite-based OLR retrieval requires angular and spectral integrations applying coefficients usually derived by Radiative Transfer Models. However, we developed a matchup method to improve validation and retrieval method that has improved accuracy of narrowband-satellite OLR. On the STEM validation method, the new OLR had improved from 10.5432 to 3.8091 W M-2 RMSE and from -8.4947 to -0.0712 W M-2 bias, as well as new OLR improved its distribution to be aligned with the fit-line in the scatterplot analysis.