Evaluation of vehicle emission in Yunnan province from 2003 to 2015

Vehicle emissions have become the major source of air pollution as well as heavy metals pollution accompanied with unprecedented economic development and urbanization in China. Yunnan province, the congruity area of undeveloped region with high vehicle population increasing, as well as special natural conditions, was taken as the study area. We estimated the vehicle emissions during 2003–2015 with COPERT IV model, including private cars (PC), buses (BUS), light duty vehicles (LDV) and heavy duty trucks (HDT), then analyzed the vehicle emission characteristics, involving CO, CO2, SO2, NOx, NO, NO2, N2O, NH3, Volatile organic compounds (VOC), Ambient Air Non-Methane Volatile Organic compound (NMVOC), CH4, PM2.5, PM10, PM (exhaust), Cadmium and Zinc. The results indicated that all pollutants as well as heavy metals were increased at different growth trends except SO2 although more stringent emission standard implementation, the rising of vehicle population become the main contributor to the vehicle emission growth, and CO2 emission was the major vehicle emissions accounted for one third of total CO2 emissions in Yunnan. PC was the main contributor to the rising of CO, VOC, NMVOC, CH4, NH3, CO2, Cadmium and Zinc, which was also the major vehicle growth type; HDT and LDV brought to the emissions of N2O, NOx, NO, PM10, NO2, PM2.5, and PM (exhaust) respectively. At last, uncertainty of emission estimation was analyzed based on the Monte Carlo simulation. The vehicle emission become one critical field of emission reduction in Yunnan which should be given greater emphasis to environmental concerns.