Increasing Temporal Variability of Global Tropical Cyclone Near‐Storm Rainfall Under Global Warming: Insights From CMIP6 HighResMIP Simulations

Abstract Tropical cyclone (TC) rainfall poses a significant threat to coastal regions, particularly in the near‐storm region, where the inner core's strongest convection occurs. Temporal variability in the near‐storm rainfall rate over a TC's lifetime, including rapid increases and decreases in rainfall rate, impacts forecast accuracy and hazard preparedness. Using multiple HighResMIP CMIP6 simulations under the SSP5‐8.5 scenario, we find that near‐storm rainfall rate temporal variability increases under pronounced anthropogenic warming, driven primarily by elevated atmospheric moisture. Analysis of relative rainfall rate changes suggests that this heightened variability aligns with rising near‐storm rainfall rate trends. These findings have critical implications for coastal communities, highlighting not only the increased risk of near‐storm rainfall but also the rapid intensification or decline of these rainfall events.