Radial Rainfall Pattern Changes of Intense Over-Ocean Tropical Cyclones Under Global Warming: Insights From an MRI HighRes CMIP6 Simulation

Abstract

Tropical cyclone (TC) rainfall is an important hazard. Radial rainfall patterns of intense over-ocean TCs under global warming are investigated using the MRI HighRes Coupled Model Intercomparison Project Phase 6 simulation with the SSP5-8.5 high-emission scenario. These patterns are characterized by four parameters: rainfall at the cyclone center (Formula presented.), maximum rainfall (Formula presented.), radius of maximum rainfall (Formula presented.), and e-folding radius (Formula presented.). We find (Formula presented.) strongly correlates (Formula presented.) with a moisture convergence proxy—boundary-layer maximum wind times column moisture divided by the radius of maximum wind—across different intensities and under climate change. Under warming, mean (Formula presented.) and (Formula presented.) increase by 8.65%/K and 8.86%/K, while (Formula presented.) and (Formula presented.) shrink by 1.03%/K and 1.79%/K, respectively. Notably, under warming, (Formula presented.) exhibits greater sensitivity to TC intensity, and its increases are mainly attributed to column moisture increase.