[Establishment of a High-resolution Anthropogenic Emission Inventory and Its Evaluation Using the WRF-Chem Model for Lanzhou].

ABSTRACT

City-scale high-resolution anthropogenic emission inventories are an important tool for ambient air quality forecasting and early warning, the analysis of underlying causes, and policy making. At present, city-scale anthropogenic emissions inventories for use in air quality models are scarce for West China. By studying the literature on emission inventories, this paper establishes a city-scale anthropogenic emission inventory for Lanzhou (HEI-LZ16) as the basis for an air quality model. The weather research and forecasting with chemistry (WRF-Chem) model was used to evaluate the applicability of the emission inventory at different resolutions in Lanzhou. The results showed that the emission amounts of SO2, NOx, CO, NH3, VOCs, PM10, PM2.5, BC, and OC in Lanzhou were 25642, 53998, 319003, 10475, 35289, 49250, 19822, 2476, and 1482 t·a-1 in 2016,respectively. Compared with the simulation scenario of multi-resolution emission inventory for China (MEIC), normalized mean error (NME) of O3 and PM2.5 under the HEI-LZ16 scenario decreased by 140.2% and 28.8%, respectively. The HEI-LZ16 inventory is more suitable for application in air pollution research in Lanzhou, which was verified by the WRF-Chem model and the observational data. The spatiotemporal distributions of PM2.5 and O3 were also analyzed using the HEI-LZ16 scenario. The ozone concentration of the maximum daily 8-h average (MDA8) in Lanzhou was low in urban areas and high in the suburbs during winter and spring, and high in the west of the urban valley and its downwind areas during summer and autumn. MDA8 in summer and autumn was influenced by easterly winds and photochemical reactions. In winter, ozone concentrations in urban areas are suppressed by NOx emissions but the concentration decreases. High PM2.5 concentrations are mainly concentrated within the Yellow River Valley. This study shows that there is a pollutant transmission channel along the western side of the Baiyin-Lanzhou Yellow River Valley, which has a greater impact on the ambient air quality in Lanzhou.