摘要
基于WRF-CAMx(the weather research and forecasting model and the comprehensive air quality model with extensions)空气质量模型定量分析了不同NO_(x)、挥发性有机物(volatile organic compounds,VOCs)在减排情景下全国及重点区域PM_(2.5)与O_(3)浓度变化情况,并通过引入敏感度的概念,评估PM_(2.5)与O_(3)对NO_(x)、VOCs减排的敏感性,直观地揭示了NO_(x)、VOCs减排对PM_(2.5)与O_(3)浓度改善效益,以此提出中国PM_(2.5)与O_(3)协同控制路径.模拟结果表明,NO_(x)减排可有效降低全国及重点区域PM_(2.5)与O_(3)浓度,减排比例较小时,PM_(2.5)浓度下降,但少部分区域O_(3)浓度升高,随着减排比例增加,PM_(2.5)与O_(3)浓度均呈加速下降趋势;VOCs减排过程中,全国及重点区域PM_(2.5)与O_(3)浓度一直保持下降趋势.减排敏感度结果表明,全国及重点区域PM_(2.5)对NO_(x)减排敏感度更高;而O_(3)有所不同,对于全国整体而言,对NO_(x)减排更敏感;重点区域中珠江三角洲地区O_(3)对VOCs减排敏感度更高;“2+26”城市、长江三角洲、汾渭平原地区O_(3)在减排比例较小时,对VOCs减排更敏感,随着减排比例增加,对NO_(x)减排敏感度更高.因此,建议在中长期大气污染物协同减排路径的设计中,将NO_(x)持续减排作为全国及重点区域PM_(2.5)与O_(3)污染改善的核心,将VOCs减排作为短期内降低重点区域PM_(2.5)与O_(3)浓度的关键.
Since the Air Pollution Prevention and Control Action Plan was issued in 2013,air quality in China has significantly improved.But the concentration of fine particulate matter(PM_(2.5))remains 3 times higher than the guideline value of the WHO(World Health Organization,2015),and the rising concentration of ozone(O_(3))that has caused premature death and economic losses neutralized the environmental benefits brought in by partial reductions of PM_(2.5).The coordinated control of PM_(2.5)and O_(3),hence,has been put at the top of the agenda for China’s air pollution prevention and control.Given nitrogen oxides(NO_(x))and volatile organic compounds(VOCs)are major precursors of both PM_(2.5)and O_(3),reducing the emissions of NO_(x) and VOCs is considered as the key to the coordinated control of PM_(2.5)and O_(3).Focused on the common precursors of PM_(2.5)and O_(3),our research conducted qualitative analysis of the effects of reduced emissions of NO_(x) and VOCs,and suggested China’s path to coordinated control of PM_(2.5)and O_(3).The results are expected to be adopted as scientific bases by administrative authorities for relevant policy-making.Our research was based on the WRF-CAMx model and scenario analysis was used.Different scenarios where NO_(x) and VOCs emissions were reduced to different degrees were set to simulate the changes of concentrations of PM_(2.5)and O_(3)across China and in key areas.The indicator of sensitivity was introduced to quantitively evaluate the responsiveness of PM_(2.5)and O_(3)concentrations to the reduced emissions of NO_(x) and VOCs.The effects of reduced emissions of NO_(x) and VOCs on the concentrations of PM_(2.5)and O_(3)were revealed directly in the research.As suggested by simulation results,the reduction of NO_(x) or VOCs emission can contribute to the decrease of the concentration of PM_(2.5)nationwide and in key areas.If at the same ratio of reduction,the reduction of NO_(x) emission can lead to a larger decrease of PM_(2.5)concentration.The change of O_(3)concentration nationwide or in key areas varies under different NO_(x) and VOCs emission reduction scenarios.From the perspective of the whole country,a small ratio of NO_(x) emission reduction may lead to the rise of O_(3)concentration in some areas,but the O_(3)concentration declines on the whole,and the rate of decline rises with the further reduction of NO_(x) emission.The reduction of VOCs emission can decrease the O_(3)concentration nationwide,but the effect is less obvious than the reduction of NO_(x) emission.For the Pearl River Delta area,the reduced emission of VOCs is more effective for the decrease of O_(3)concentration.For the“2+26”cities,the Yangtze River Delta,and the Fenwei Plain,if on a small scale,the reduction of VOCs is more effective for the decrease of O_(3)concentration than that of NO_(x).But due to the existence of natural VOCs,the proportion of artificial VOCs to the total emission of VOCs reduces as the artificial VOCs continues to decline,and hence,the benefit of the reduction of VOCs becomes less obvious than that of NO_(x).Sensitivity results were in agreement with the concentration changes.Based on the abovementioned results,to realize the balance of the benefits of NO_(x) and VOCs emissions reduction between the local and global and between the short term and the long term,we suggest that the continuous reduction of NO_(x) emission should be regarded as the focus of coordinated control of PM_(2.5)and O_(3)in terms of both the whole country and key areas and the reduction of VOCs emission is the key to the improvement of O_(3)pollutions in key areas in the short term,which should be incorporated in the medium-to-long-term design of China’s path to coordinated control of air pollutions.
作者
刘鑫
史旭荣
雷宇
薛文博
Xin Liu;Xurong Shi;Yu Lei;Wenbo Xue(Center of Air Modeling and Systems Analysis,Chinese Academy for Environmental Planning,Beijing 100012,China;State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation,Chinese Academy for Environmental Planning,Beijing 100012,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2022年第18期2089-2099,共11页
Chinese Science Bulletin
基金
国家自然科学基金(72171157)资助。
关键词
NO_(x)
挥发性有机物
PM_(2.5)
O_(3)
WRF-CAMx模型
NO_(x)
volatile organic compounds
PM_(2.5)
O_(3)
the weather research and forecasting model and the comprehensive air quality model with extensions(WRF-CAMx)
