Effects of Warming and Stratospheric Aerosol Injection on Tropical Cyclone Distribution and Frequency: Results From a High‐Resolution Global Circulation Model

Abstract As global circulation models (GCMs) have increased in spatial resolution, more realistic tropical cyclones (TCs) and TC distributions have been simulated. Whereas prior research on TC climatologies has relied on proxies like Potential Intensity and synthetic storm models, the cyclones simulated by newer TC‐resolving GCMs can now be analyzed directly. This is particularly useful for studying projected global storm distributions under radically altered future climates, including high‐emissions warming scenarios, and those shaped by climate interventions. In this paper, we utilize a high‐resolution model configuration to conduct experiments examining the effects of Stratospheric Aerosol Injection (SAI) on tropical cyclones. These experiments are constructed based on prior work on SAI, using the Geoengineering Large Ensemble Project (GLENS) ensemble. Our analysis focuses on three uncoupled 10‐year simulations conducted using 30‐km grid spacing and forced with modeled sea surface temperatures from earlier work. The first is a recent‐past calibration run. The second simulates the Shared Socioeconomic Pathway (SSP) 5–8.5, for the years 2090–2099, with no SAI. The third simulation also uses SSP 5–8.5 for the years 2090–2099, but with SAI keeping global temperature rise at no more than 1.5 K. We use a novel TC tracking scheme to analyze resulting changes in storm tracks and properties. Our results show that while SAI may return global storm counts back to late 20th‐century levels, there are still large basin‐by‐basin changes in storm number and intensity. These are likely driven by increases in mean ENSO indices that occur with warming, but seemingly also with intervention.