Precipitation extremes have substantial implications for both human and natural systems, shown to have already increased and to further increase with future warming. Extreme precipitation is expected to increase with warming from a simple thermodynamic relation that implies an exponential increase in atmospheric moisture with temperature. However, within the tropics, the rate of intensification in extreme precipitation with warming is twice as large as that implied by the thermodynamic argument, hinting at an unknown contribution from atmospheric dynamics. Dai and Soden  reveal that the degree of cloud clustering (i.e., convective aggregation) amplifies the response of tropical precipitation extremes to surface warming on a year-to-year basis in both satellite observations and climate model simulations. More specifically, precipitation extremes and convective aggregation increase during El Niño events compared to La Niña events. The newly revealed linkage between convective aggregation and precipitation extremes offer insights into their potential response to future warming.
Citation: Dai, N. & Soden, B. . Convective Aggregation and the Amplification of Tropical Precipitation Extremes. AGU Advances, 1, e2020AV000201. https://doi.org/10.1029/2020AV000201
—Sarah Kang, Editor, AGU Advances