Anthropogenic forcing changes coastal tropical cyclone frequency

It remains a mystery if and how anthropogenic climate change has altered the global tropical cyclone (TC) activities, mainly due to short reliable TC observations and climate internal variabilities. Here we show with large-ensemble TC-permitting simulations that the observed increases in TC frequency since 1980 near the US Atlantic coast and Hawaii are likely related to the aerosol and greenhouse gases (GHG) effects, respectively. The observed decrease in the South China Sea after 1980 could be associated with GHG emissions alone, whereas the observed increase near Japan and Korea during this period would be related to the aerosol and GHG combined effects. These changes in coastal TC frequency are explained by the responses of large-scale environmental conditions to anthropogenic forcing.