[Impact of Emission Reduction in Different Sectors on Air Quality and Atmospheric Temperature in Eastern China]

China's emission reduction policy will focus on the synergistic control of air pollution and atmospheric warming in future. However, the impacts of emission reductions in different sectors on air quality and atmospheric temperature vary significantly. Using a two-way coupled air quality model(WRF-Chem), this study quantified the impacts of anthropogenic emission reductions from various sectors(industrial, residential, transportation, thermal power plants, and agricultural sectors) on air quality and atmospheric temperature in eastern China in September 2016. Emission reduction from industrial, residential, transportation, thermal power plant, and agricultural sources could effectively improve air quality, with PM_2.5 reduction of 33.9%, 9.6%, 15.8%, 10.8%, and 26.7%, respectively; however, the weakened aerosol-radiation interactions resulted in more energy at the surface, further increasing the near-surface air temperature by 0.04, 0.03, 0.01, 0.03, and 0.09℃. At the top of the atmosphere, the net radiation flux decreased by 0.3, 0.8, 0.7, and 0.1 W·m^-2 owing to the emission reduction from industrial, residential, traffic, and thermal power plant sectors, whereas the emission reduction from agricultural sources resulted in an increase in the net radiation flux of 0.8 W·m^-2. On one hand, the emission reduction from agricultural sources led to a decrease in scattering aerosols and increase in the net radiation flux; contrastingly, it did not lead to a decrease in absorbing aerosols(black carbon), which could not offset the radiation increase caused by the decrease in scattering aerosols. Therefore, the emission reduction from agricultural sources led to the increase in net radiation flux at the top of the atmosphere and the most significant increase in near-surface temperature. It is noted that in the future, although emission reduction from agricultural sources will bring about significant air quality improvement, it will also consequently cause significant warming.