Hamilton Airshed Modelling System

摘要

The Hamilton Airshed Modelling System (HAMS) was developed to provide a platform to better understand the processes and contributions to Hamilton’s air quality and to inform future policy and human health impact decisions. As air quality in an urban airshed is influenced by many factors including local, regional and transboundary sources, as well as by the geographical features and prevailing meteorological conditions, the CMAQ-WRF-SMOKE regional modeling platform was selected. This airshed modelling system can handle various types of emission sources and profiles as well as the transportation, dispersion and chemical reactions of contaminates in a complex geographic area to achieve realistic simulations of air quality. The air quality in the Hamilton Region was modelled by tracking the emission, dispersion and chemical transformation of twenty selected contaminants in the airshed, with a focus on NOX, SO2, O3 and particulate matter (PM2.5 and PM10). Emphasis was also placed on benzene and benzo(a)pyrene (B[a]P) for health and regulatory reasons. The modelling is completed using four levels of nested spatial grids, providing both regional and local contributions to the air quality. The Hamilton airshed is part of the larger southern Ontario airshed, with in-fluences from both south-western Ontario and the United States. The influences each have different emission profiles with respect to contaminants, quantity of emissions, and types of sources (e.g., stacks, roadways, area), as well as the specific location of the sources.