Tropical volcanic eruptions enhance global tropical cyclone geneses

The influence of strong tropical volcanic eruptions (TVEs) on global tropical cyclone (TC) genesis frequency (TCGF) remains poorly understood. Here, we utilize global reanalysis data and high-resolution large ensemble simulations to uncover a robust link between TVEs and enhanced global TCGF. We find a significant increase in TCGF over the Pacific within two years following strong TVEs, accompanied by an insignificant decrease over the South Indian Ocean, leading to a net global TCGF increase. TVEs reduce precipitation over the Maritime Continent, lower global mean sea surface temperature (SST) but increase SST in the equatorial central Pacific, inducing an El Niño-like SST anomaly pattern. These anomalies weaken the Walker Circulation, creating favorable conditions for TC genesis over the Pacific and thus resulting in an increase in TCGF. Our results provide new insights into the climate impacts of TVEs on global and regional TC activity.