Abstract:This study uses two sets of experiments from the Coupled Model Intercomparison Project Phase 6 (CMIP6), as well as the idealized results from the Linear Baroclinic Model experiments, to investigate the responses of Asian summer monsoon to the dipole pattern of anthropogenic aerosol forcing in Asia and their physical mechanisms. Since the 21st century, the anthropogenic aerosol emission over South Asia has kept its increasement, while it increases in the first decade and then rapidly decreases over East Asia, and this feature will continue in the future. In the coupled climate system considering both the direct atmospheric responses and the sea surface temperature mediated atmospheric responses, the East Asian summer monsoon (EASM) is strengthened by the intensified and westward shifted western Pacific subtropical high, and the precipitation is intensified as well. In the direct atmospheric responses without considering the coupled ocean-atmosphere interaction processes, the declined East Asian anthropogenic aerosol emissions increase the land-sea thermal contrast by inducing an anomalous land warming due to their radiative effect, which also strengthens the EASM and precipitation by generating the cyclonic surface pressure anomaly in the East Asian land regions. For the South Asian summer monsoon (SASM), it shows more complicated responses due to the dipole pattern of anthropogenic aerosol forcing, with weakened SASM and reduced precipitation in the direct atmospheric responses but a gently intensified SASM in the coupled responses with increased precipitation anomalies in the Indian sub-continent. This suggests the important role of the coupled ocean-atmosphere interaction processes in shaping the regional climate responses to anthropogenic aerosol forcing. In addition, by using the Linear Baroclinic Model experiments, it demonstrates that the atmospheric heating anomaly resulted from the anthropogenic aerosol emissions in East Asia and South Asia may not only lead to localized summer monsoon responses, but also can regulate the larger-scale summer monsoon circulation changes by causing the surface pressure anomalies remotely.