The role of meteorological conditions and pollution control strategies in reducing air pollution in Beijing during APEC 2014 and Victory Parade 2015

摘要

To control severe air pollution in China, comprehensive pollutioncontrol strategies have been implemented throughout the country inrecent years. To evaluate the effectiveness of these strategies, theinfluence of meteorological conditions on levels of air pollutionneeds to be determined. Using the intensive air pollution controlstrategies implemented during the Asia-Pacific Economic CooperationForum in 2014 (APEC 2014) and the 2015 China Victory Day Parade (Victory Parade 2015) asexamples, we estimated the role of meteorological conditions andpollution control strategies in reducing air pollution levels inBeijing. Atmospheric particulate matter of aerodynamicdiameter  ≤ 2.5 µm (PM) samples werecollected and gaseous pollutants (SO, NO, NO, andO) were measured online at a site in Peking University(PKU). To determine the influence of meteorological conditions onthe levels of air pollution, we first compared the air pollutantconcentrations during days with stable meteorologicalconditions. However, there were few days with stable meteorologicalconditions during the Victory Parade. As such, we were unable to estimate thelevel of emission reduction efforts during this period. Finally,a generalized linear regression model (GLM) based only onmeteorological parameters was built to predict air pollutantconcentrations, which could explain more than 70 % of thevariation in air pollutant concentration levels, after incorporatingthe nonlinear relationships between certain meteorologicalparameters and the concentrations of air pollutants. Evaluation ofthe GLM performance revealed that the GLM, even based only onmeteorological parameters, could be satisfactory to estimate thecontribution of meteorological conditions in reducing air pollutionand, hence, the contribution of control strategies in reducing airpollution. Using the GLM, we found that the meteorologicalconditions and pollution control strategies contributed 30 and28 % to the reduction of the PM concentrationduring APEC and 38 and 25 % during the Victory Parade, respectively, based on theassumption that the concentrations of air pollutants are onlydetermined by meteorological conditions and emission intensities. Wealso estimated the contribution of meteorological conditions andcontrol strategies in reducing the concentrations of gaseouspollutants and PM components with the GLMs, revealingthe effective control of anthropogenic emissions.