Effects of Tropical Sea Surface Temperature Variability on Northern Hemisphere Tropical Cyclone Genesis

Abstract This study quantifies the contributions of tropical sea surface temperature (SST) variations during boreal warm season to interannual-to-decadal variability in cyclone genesis frequency (TCGF) over Northern Hemisphere ocean basins. The first seven leading modes SST are found affect basinwide TCGF one or more basins, and related canonical El Niño–Southern Oscillation (ENSO), global warming (GW), Pacific meridional mode (PMM), Atlantic multidecadal oscillation (AMO), decadal (PDO), (AMM). These account for approximately 58%, 50%, 56% variance 1969–2018 North (NA), northeast (NEP), northwest (NWP) Oceans, respectively. effect is weak on north Indian Ocean. dominating differ among basins: ENSO, AMO, AMM, GW dominant NA; ENSO AMO NEP; PMM, interannual NWP. A specific may have opposite effects different particularly between NA NEP. Sliding-window multiple linear regression analyses show that stable time NWP, but strengthened since 1990s local TC occurrence also explored, underlying physical mechanisms examined by diagnosing a potential index its components.