Abstract
Abstract. We examine the potential benefits of very high resolution for air-quality forecast simulations using a nested system of the Global Environmental Multiscale – Modelling Air-quality and Chemistry chemical transport model. We focus on simulations at 1 and 2.5 km grid-cell spacing for the same time period and domain (the industrial emissions region of the Athabasca oil sands). Standard grid cell to observation station pair analyses show no benefit to the higher-resolution simulation (and a degradation of performance for most metrics using this standard form of evaluation). However, when the evaluation methodology is modified, to include a search over equivalent representative regions surrounding the observation locations for the closest fit to the observations, the model simulation with the smaller grid-cell size had the better performance. While other sources of model error thus dominate net performance at these two resolutions, obscuring the potential benefits of higher-resolution modelling for forecasting purposes, the higher-resolution simulation shows promise in terms of better aiding localized chemical analysis of pollutant plumes, through better representation of plume maxima.
Highlights
Numerical modelling of the atmosphere in an Eulerian framework relies on discretization of the computational domain into a numerical grid
We examine the impact of grid-cell size on model performance in a region of intense petrochemical extraction and upgrading, the Athabasca oil sands region (AOSR)
The air-quality model used in this work is Environment and Climate Change Canada’s (ECCC) Global Environmental Multiscale – Modelling Air-quality and Chemistry (GEMMACH) model, which has been in use as Canada’s operational air-quality forecast model since 2009 (Moran et al, 2010)
Summary
Numerical modelling of the atmosphere in an Eulerian framework relies on discretization of the computational domain into a numerical grid. As grid resolution reaches the 3 to 4 km scale, explicit cloud microphysics packages may be used, allowing potentially better performance, with regards to feedbacks between meteorology and chemistry (Yu et al, 2014; Gong et al, 2015). While these models promise better physical representation of local chemistry, their performance may be limited by the quantity and availability of initialization and boundary condition meteorological data; these data may be used in a data assimilation context to improve their initial state. Some recent air-quality model simulation studies with grid-cell sizes on the order of 1 to 4 km include Thompson and Selin (2012), Li et al (2014), Joe et al (2014), Kheirbek et al (2014, 2016), and Pan et al (2017)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
