Effect of Regional Anthropogenic Aerosols on Tropical Cyclone Frequency
of Occurrence
Abstract
Previous studies highlighted the distinct impact of anthropogenic
aerosols from the Western and Eastern Hemispheres on the past
multi-decadal changes in tropical cyclone frequency of occurrence (TCF).
However, the detailed effect of subregional aerosol changes on TCF
changes remained unclear. Using idealized simulations with a dynamical
climate model, this study reveals that reduced aerosol emissions from
Europe and the U.S. since 1980 may have equally contributed to increased
TCF over the North Atlantic, with Europe playing a major role in
decreased TCF in the Southern Hemisphere. Additionally, increased
aerosol emissions from India since 1980 may have played a major role in
decreasing TCF over the western North Pacific compared to increased
emissions from China. TCFs are projected to decrease for most global
tropics toward the end of this century due to the dominant effect of
increasing greenhouse gases.