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Abstract Global mean and extreme tropical cyclone (TC) precipitation have been increasing over the past few decades and are expected to continue to increase into the future due to climate change. Most projections of future TC precipitation use climate models with grid spacings of 25–100 km, which are too coarse to resolve the convective structures and small‐scale precipitation processes within TCs. This work uses convection‐permitting Weather Research and Forecasting model simulations to investigate how precipitation and precipitation processes change in the inner core (IC) and outer rainbands (OR) of TCs in response to sea surface temperature (SST) warming. The simulations are idealized, with single TCs initialized from weak vortices over domain‐constant SSTs. In these simulations, TC intensity and IC precipitation greatly increase with SST warming while OR precipitation increases slightly. A greater area in the IC is occupied by deep convection more frequently in the warmer simulations, while the deep convective activity remains relatively constant with warming in the TC OR. Mixing ratios of hydrometeors and cloud ice increase with warming in both the IC and OR, while the TCs' vertical circulations deepen, melting levels rise, and mean upward velocities strengthen. This work demonstrates how analysis of three‐dimensional storm structures can provide insight into processes that change TC precipitation in different regions of the storm, and future work will include applying this analysis to more realistic convection‐permitting simulations. 

Abstract This work explores the impact of rotation on tropical convection and climate. As our starting point, we use the RCEMIP experiments as control simulations and run additional simulations with rotation. Compared to radiative convective equilibrium (RCE) experiments, rotating RCE (RRCE) experiments have a more stable and humid atmosphere with higher precipitation rates. The intensity of the overturning circulation decreases, water vapor is cycled through the troposphere at a slower rate, the subsidence fraction decreases, and the climate sensitivity increases. Several of these changes can be attributed to an increased flux of latent and sensible heat that results from an increase of near‐surface wind speed with rotation shortly after model initialization. The increased climate sensitivity results from changes of both the longwave cloud radiative effect and the longwave clear‐sky radiative fluxes. This work demonstrates the sensitivity of atmospheric humidity and surface fluxes of moisture and temperature to rotation. 

Abstract Understanding how extreme weather, such as tropical cyclones, will change with future climate warming is an interesting computational challenge. Here, the hindcast approach is used to create different storylines of a particular tropical cyclone, Hurricane Irma (2017). Using the community atmosphere model, we explore how Irma’s precipitation would change under various levels of climate warming. Analysis is focused on a 48 h period where the simulated hurricane tracks reasonably represent Irma’s observed track. Under future scenarios of 2 K, 3 K, and 4 K global average surface temperature increase above pre-industrial levels, the mean 3-hourly rainfall rates in the simulated storms increase by 3–7% K⁻¹compared to present. This change increases in magnitude for the 95th and 99th percentile 3-hourly rates, which intensify by 10–13% K⁻¹and 17–21% K⁻¹, respectively. Over Florida, the simulated mean rainfall accumulations increase by 16–26% K⁻¹, with local maxima increasing by 18–43% K⁻¹. All percent changes increase monotonically with warming level.