Radiative effects of observationally constrained tropical upper-level clouds in a radiative-convective equilibrium model

Abstract Tropical upper-level clouds (TUCs) control the radiation budget in a climate system and strongly influence surface temperatures. This study examines global mean temperature changes due to percent change TUC cover, which is referred as tropical cloud radiative effect (TUCRE, units of Kelvin per %). We use radiative-convective equilibrium model that can both upper- lower-level layers separately three idealized regions (extratropics, moist, dry regions) two sub-regions (clear-moist cloudy-moist within moist regions. In simulation, reflectivity based on fraction assumes primary role determining TUCRE. Accurate estimate TUCRE requires careful prescriptions according actual satellite observations. extent obtained from 18 years (2003–2020) data daily MODIS properties. Our results show estimated net ranges 0.19 0.33 K/%, with higher leading temperatures (a warming effect) system. means longwave dominates over shortwave When interplay model, range was greater combination layers, although all values were positive. The by 0.22 0.40 K/% when are negatively coupled, because Earth warms decline reflectance solar radiation. positively lower 0.14 0.30 less reaches through combined layers. Finally, we test sensitivity five fractions 15 combinations reflectivity. Comparing our TUCREs models will help us understand how cover affects climate, should greatly reduce uncertainty associated feedback.