Abstract:Using anthropogenic aerosol single-forcing simulations from the Coupled Model Intercomparison Project Phase 6 and East/South Asia regional anthropogenic aerosol forcing simulations from the Regional Aerosol Model Intercomparison Project, we investigate the impacts of the Asian dipole pattern of anthropogenic aerosol emissions, characterized by "East Asian emission reduction and South Asian emission increase" since the 2010s, on the North Pacific sea surface temperature (SST) and its underlying mechanisms. Results show that under the anthropogenic aerosol single-forcing simulations with opposite aerosol emissions changes between East and South Asia, the North Pacific SST shows a warming trend. However, the regional simulations reveal the distinct North Pacific SST responses to East Asian emissions reduction versus South Asian emissions increase: East Asian emissions reduction induces the SST warming in the high-latitude North Pacific and the west coast of North America, whereas South Asian emissions increase leads to the SST cooling in the corresponding regions. Further analyses indicate that the East Asian emissions reduction induces the North Pacific SST warming by modulating the shortwave radiation and the corresponding mid-latitude atmospheric teleconnection, while the South Asian emissions increase triggers the atmospheric circulation anomalies over the North Indian Ocean via radiative cooling effect, subsequently causing the SST cooling in the equatorial eastern Indian Ocean. This SST cooling weakens the Walker circulation and generates a northward-propagating atmospheric teleconnection wave train that propagates the tropical signals to the North Pacific. Then it modifies the North Pacific SST by altering the localized atmospheric circulation. Additionally, by comparing the results between the anthropogenic aerosol single-forcing simulations and those from the regional anthropogenic aerosol forcing simulations, we find that the North Pacific SST variations under the Asian dipole pattern of aerosol emissions are dominated by the anthropogenic aerosol emissions reduction from East Asia.