Response of African Easterly Waves to a Warming Climate: A Convection-Permitting Approach

As the atmosphere warms, tropical cyclones (TCs) and their precursors, like African easterly waves (AEWs), will respond. While TC changes in a warmer climate have been studied, AEW evolution remains uncertain. Using a novel storm-resolving regional Model for Prediction Across Scales setup, we examine the response of AEWs during an active historic period. Our findings indicate that AEWs over Africa will become significantly more intense, wetter, and with greater water vapor content. Future AEWs in this scenario and period will also experience a larger saturation deficit over the continent, indicating significant changes in both temperature and moisture influencing growth. The location of AEWs does not change under the future climate scenario, but TC genesis and overall AEW propagation for a case study is slower. Slower progression of AEWs can have dangerous ramifications, including prolonged periods of heavy rainfall, increasing the risk of flooding over Africa. These results highlight the need for high-resolution modeling to better understand AEW behavior in a warming climate and their potential impacts on extreme weather.