A Machine Learning Approach to Determine Surface Radiative Fluxes based on CERES Observations

Jay Garg; PC Sawaengphokhai; Paul W Stackhouse, Jr.; Walter F Miller; Hunter F Winecoff

NASA NTRS · 20230017760

A Machine Learning Approach to Determine Surface Radiative Fluxes based on CERES Observations

Jay Garg·PC Sawaengphokhai·Paul W Stackhouse, Jr.·Walter F Miller·Hunter F Winecoff

Abstract

The Clouds and Earth’s Radiant Energy System (CERES) projects provides satellite-based observations of the radiative fluxes and clouds systems. CERES climate quality data products typically take several months of calibration and validation before release to the public. An alternative data product, Fast Longwave and Shortwave radiative Flux (FLASHFlux), was created to provide data to the applied sciences and educational users. FLASHFlux provides Top-of-Atmosphere radiative fluxes, Clouds properties, and parameterized surface radiative fluxes within four days for footprint (Level 2) data. We investigate the use of Artificial Neural Network (ANN) using MODerate resolution Imaging Spectroradiometer (MODIS) derived clouds properties and meteorology from the Global Assimilation and Meteorology Office (GMAO) scaled to the CERES footprint from the CERES Clouds Radiative Swath (CRS) data product to compute surface radiative fluxes. We test ANN produce fluxes against surface fluxes produced from the Fu-Liou model used in CRS and the Langley Parameterized Shortwave Algorithm (LPSA) and Langley Parameterized Longwave Algorithm (LPLA) used in FLASHFlux. We also validated each model with ground-based observations. Furthermore, we investigate Leave-One-Feature-Out Importance (LOFO) to evaluate the significance of each feature in our training and provide insight for future models. Advances in machine learning, along with increases in computational capabilities and available data allow us to estimate effects of unresolved processes in our climate without direct modeling. This work evaluates the ability to create accurate data-driven models to supplement or replace current models that estimate surface radiative fluxes.

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Jay Garg, PC Sawaengphokhai, Paul W Stackhouse, Jr., Walter F Miller, Hunter F Winecoff. A Machine Learning Approach to Determine Surface Radiative Fluxes based on CERES Observations. https://ntrs.nasa.gov/citations/20230017760

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