Projected Poleward Migration of Western North Pacific Tropical Cyclone Genesis

The recently-observed poleward shift in western North Pacific tropical cyclone (TC) genesis has increased the TC threat to East Asia. We find that the poleward shift of TC genesis since 1979 is linked to mega-ENSO. A downscaling analysis of TC genesis latitude given the constraint of mega-ENSO using 30 models from the Coupled Model Intercomparison Project Phase 6 (CMIP6) show a continued increasing poleward shift with additional warming. We use the dynamic genesis potential index as a TC proxy in future CMIP6 simulations. These simulations show enhanced TC formation in the subtropics and decreased TC formation in the tropics. Modeled TCs in CMIP6 high-resolution models that well represent mega-ENSO project future poleward shifts in TC genesis. Both observations and simulations show that extra-tropical North Pacific sea surface temperature warming associated with mega-ENSO are the primary driver of the TC genesis poleward shift. Our study provides new insights into climate change-driven TC migration.