Contrasting Responses of Atlantic and Pacific Tropical Cyclone Activity to Atlantic Multidecadal Variability

This research assesses the influences of Atlantic Multidecadal Variability (AMV) on global tropical cyclones (TCs) using two large ensembles idealized climate model simulations with opposite signs AMV forcings superimposed (i.e., AMV+ and AMV–). We first detect TCs then compare TC activity by basin in experiments. find contrasting responses Pacific frequency to anomalies. Compared AMV–, significantly increases North Atlantic, including those making landfalls. The increase is explained warmer sea surface temperature, higher relative humidity, increased vorticity, weaker vertical wind shear under AMV+. By contrast, decreases occurrence over western South Pacific, which tied stronger lower humidity. are attributed strengthened Walker Circulation between Pacific.