Characteristics of Aerosols and Clouds and Their Role in Earth's Energy Budget

Clouds and aerosols provide the greatest uncertainty in estimating and interpreting Earth's energy budget. This study not only focuses on surface brightening/dimming, but also explores Earth's energy balance. The validation re-sults of the CERES-SYN, ISCCP-FH, and GEWEX-SRB datasets with Baseline Surface Radiation Network (BSRN), Sur-face Radiation Budget Network (SURFRAD), and CMA observations show that CERES data have the highest accuracy and the longest temporal coverage. The role of clouds and aerosols in Earth's energy budget was explained using CERES and MERRA-2 products. The results show that Earth's energy increases at a rate of 0.63 W m-2 decade-1 in 2000-21. The global surface brightens at a rate of 0.57 W m-2 decade-1, with surface energy decreasing at a rate of 0.19 W m-2 decade-1. Brightening was found over Australia, central Asia, and southern Africa, mainly associated with cloud reduction, with aerosol emissions reductions contributing to the East Asian surface brightening. The surface brightening in South America and Southeast Asia is also due to the reduction of clouds. The increase of aerosols in South Asia is the main factor for its surface dimming, while we infer that the climatic effect from the increase of black carbon (BC) aerosols in South Asia is the inducing factor for the dimming in southern China. The surface darkening in West Asia is the result of the combined effect of clouds and aerosols, while in northern Africa it may be related to the increase of clouds caused by the decrease of dust aerosols. Surface energy increases only in Southeast Asia, South America, and Europe.