Effect Simulation of Responding Measures During a Heavy Pollution Red Alert in Tianjin City

Abstract

The WRF/SMOKE/CMAQ model is used to simulate a heavy pollution process in the winter of 2016 in Tianjin. Three types of simulation scenarios are set up for the activation of red alert due to the “Tianjin Heavy Pollution Weather Emergency Plan”. The extinction effect of emergency measures on PM2.5 concentration is assessed quantitatively. Simulation results show that during this red alert period, a 30% reduction of industrial production can be implemented to reduce the average PM2.5 concentration by 3% to 10%, while odd-and-even license plate rule of motor vehicle can be implemented to reduce the average PM2.5 concentration in the city by 3% to 5.5%.The simultaneous implementation of two measures can reduce the average PM2.5 concentration by 5% to 12%.From the perspective of PM2.5 peak and mean drop under the three control scenarios, the control effect of industrial limited production measures on the peak value is more obvious than the mean value. The control effect of the vehicle’s line-limit measures on the mean is more obvious than the peak value. The control effect of the peak value and mean value control of PM2.5 under industrial and motor vehicle simultaneous measure scenarios is similar to that of industrial limited production measures. It shows that industrial emissions are still the main source of contribution during heavy pollution, and that vehicle control has played a certain role.