PM2.5 and tropospheric O3 in China and an analysis of the impact of pollutant emission control

This study reviewed the status of PM2.5 and tropospheric O3 observations in China (15–55°N, 72–136°E). Initially, the distribution of tropospheric O3 over the globe and China was determined based on satellite observations made during 2010–2013. The annual mean values were 29.78 DU and 33.97 DU over the globe and China, respectively. The distribution of PM2.5 and seasonal changes in concentrations in China were then simulated using an aerosol chemistry–climate coupled model system, with an annual mean value of 0.51 × 10−8 kg m−3. The contributions from five different aerosols to the simulated PM2.5 concentrations in different seasons were also determined. The relationships among the emissions of aerosols, greenhouse gases and their precursors and radiative forcings were determined with reference to the (IPCC AR5) Intergovernmental Panel on Climate Change the Fifth Assessment Report. From these relationships, the possible effects of controlling O3 precursors and (PM) particulate matter on the climate were considered. The influence of the control of O3 precursors was not totally clear, and reducing emissions of short-lived greenhouse gases and black carbon was considered a secondary measure for short-term (the next 50 years) climate-change mitigation. Reducing emissions of CO2 is still the best strategy for meeting the target of a global average rise in surface air temperature of less than 2 °C. Near- and short-term emission reduction strategies are important for both effective environmental protection and climate-change mitigation