MODELING AIR POLLUTION IN BEIJING: EMISSION REDUCTION VS. METEOROLOGICAL INFLUENCE

摘要

This case study uses the Chemical Transport ModelrnWRF-Chem to simulate and measure the efficiency ofrntemporal large-scale emission reductions under differentrnmeteorological conditions. The Nov. 2014 AsianrnPacific Economic Cooperation (APEC) summitrnprovides a unique opportunity for this study due to thernextraordinarily good and well-measured air qualityrnwhich is believed to be induced by intense emissionreductionrnmeasures by the Chinese government. Fourrncases are simulated to inter-compare between favorablernund unfavorablernmeteorological conditions (in terms of air quality) asrnwell as reduced and non-reduced emissions. Keyrnvariables of the simulation results are evaluated againstrnAERONET measurements of Aerosol Optical Depthrn(AOD) and air-quality measurements by the ChinesernMinistry of Environment (CME). The inter-comparisonrnis then performed on time- and volume-averaged totalrnconcentrations of the key variables Nitrogenous Oxidern(NOx) and Particulate Matter (PM_(2.5) and PM_(10)).