This effort was supported by the US Air Force Weather Agency (AFWA), NCAR FY07 Director Opportunity Fund, Defense Threat Reduction Agency (DTRA) Coastal-urban project, and National Science Foundation (Grants 0710631 and 0410103). This work was also supported by the National Natural Science Foundation of China (Grant Nos. 40875076, U0833001, 40505002, and 40775015). Computer time was provided by NSF MRI Grant CNS-0421498, NSF MRI Grant CNS-0420873, NSF MRI Grant CNS-0420985, the University of Colorado, and a grant from the IBM Shared University Research (SUR) program.
Heat flux, Meteorology -- Mathematical models -- Research, Weather forecasting, Climate models
To bridge the gaps between traditional mesoscale modeling and microscale modeling, the National Center for Atmospheric Research (NCAR), in collaboration with other agencies and research groups, has developed an integrated urban modeling system coupled to the Weather Research and Forecasting (WRF) model as a community tool to address urban environmental issues. The core of this WRF/urban modeling system consists of: 1) three methods with different degrees of freedom to parameterize urban surface processes, ranging from a simple bulk parameterization to a sophisticated multi-layer urban canopy model with an indoor outdoor exchange sub-model that directly interacts with the atmospheric boundary layer, 2) coupling to fine-scale Computational Fluid Dynamic (CFD) Reynolds-averaged Navier–Stokes (RANS) and Large-Eddy Simulation (LES) models for Transport and Dispersion (T&D) applications, 3) procedures to incorporate high-resolution urban land-use, building morphology, and anthropogenic heating data using the National Urban Database and Access Portal Tool (NUDAPT), and 4) an urbanized high-resolution land-data assimilation system (u-HRLDAS). This paper provides an overview of this modeling system; addresses the daunting challenges of initializing the coupled WRF/urban model and of specifying the potentially vast number of parameters required to execute the WRF/urban model; explores the model sensitivity to these urban parameters; and evaluates the ability of WRF/urban to capture urban heat islands, complex boundary layer structures aloft, and urban plume T&D for several major metropolitan regions. Recent applications of this modeling system illustrate its promising utility, as a regional climate-modeling tool, to investigate impacts of future urbanization on regional meteorological conditions and on air quality under future climate change scenarios.
Chen, Fei; Kusaka, Hiroyuki; Bornstein, Robert; Ching, Jason; Grimmond, C.S.B.; Grossman-Clarke, Susanne; Loridan, Thomas; Manning, Kevin W.; Martilli, Alberto; Miao, Shiguang; Sailor, David J.; Salamanca, Francisco P.; Taha, Haider; Tewari, Mukul; Wang, Xuemei; Wyszogrodzki, Andrzej A.; and Zhang, Chaolin, "The Integrated WRF/Urban Modeling System: Development, Evaluation, and Applications to Urban Environmental Problems" (2011). Mechanical and Materials Engineering Faculty Publications and Presentations. 45.