The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants

摘要

To examine the efficacy of China's actions to control atmospheric pollution,three levels of growth of energy consumption and three levels ofimplementation of emission controls are estimated, generating a total ofnine combined activity-emission control scenarios that are then used toestimate trends of national emissions of primary air pollutants through2030. The emission control strategies are expected to have more effects thanthe energy paths on the future emission trends for all the concernedpollutants. As recently promulgated national action plans of air pollutionprevention and control (NAPAPPC) are implemented, China's anthropogenicpollutant emissions should decline. For example, the emissions of SO₂,NO_x, total suspended particles (TSP), PM₁₀, and PM_2.5 areestimated to decline 7, 20, 41, 34, and 31% from 2010 to2030, respectively, in the "best guess" scenario that includes nationalcommitment of energy saving policy and implementation of NAPAPPC. Should theissued/proposed emission standards be fully achieved, a less likelyscenario, annual emissions would be further reduced, ranging from 17 (for primaryPM_2.5) to 29% (for NO_x) declines in 2015, and theanalogue numbers would be 12 and 24% in 2030. The uncertainties ofemission projections result mainly from the uncertain operational conditionsof swiftly proliferating air pollutant control devices and lack of detailedinformation about emission control plans by region. The predicted emissiontrends by sector and chemical species raise concerns about current pollutioncontrol strategies: the potential for emissions abatement in key sectors maybe declining due to the near saturation of emission control devices use;risks of ecosystem acidification could rise because emissions of alkalinebase cations may be declining faster than those of SO₂; and radiativeforcing could rise because emissions of positive-forcing carbonaceousaerosols may decline more slowly than those of SO₂ emissions andthereby concentrations of negative-forcing sulfate particles. Expandedcontrol of emissions of fine particles and carbonaceous aerosols from smallindustrial and residential sources is recommended, and a more comprehensiveemission control strategy targeting a wider range of pollutants (volatileorganic compounds, NH₃ and CO, etc.) and taking account of more diverseenvironmental impacts is also urgently needed.