Forood Azargoshasbi

Topic

Resilient Cities in a Warming World: Quantifying the Cooling Benefits of Urban Adaptation Strategies under Future Climate

Department of Civil Engineering

Date & location

• Monday, June 22, 2026

• 10:00 A.M.

• Engineering and Computer Science Building

• Room 468 and Virtual Defence

Reviewers

Supervisory Committee

• Dr. Laura Minet, Department of Civil Engineering, University of Victoria (Supervisor)

• Dr. Tara Troy, Department of Civil Engineering, UVic (Member)

• Dr. Adam Monahan, School of Earth and Ocean Sciences, UVic (Outside Member) 

External Examiner

• Dr. Sarah Henderson, School of Population and Public Health, University of British Columbia 

Chair of Oral Examination

• Dr. Bruce Wallace, School of Social Work, UVic

Abstract

Global population growth drives rapid urbanization. In recent years, heat stress exposure in cities has gained recognition as a growing health concern. Heat stress exposure is very likely to increase as a direct consequence of climate change through more frequent and intense hot summers. Cities are implementing strategies to reduce the impacts of heatwaves by minimizing the urban heat island effect, a phenomenon that leads to higher temperatures in urban areas than in their surrounding rural areas. These heat mitigation interventions include blue (e.g., lakes, fountains, and water spray), gray (e.g., shade), and green (e.g., urban forestry and parks) strategies. However, the effectiveness of these strategies remains uncertain, especially in cold-climate cities like those in Canada, due to limited historical data on urban temperatures. The goal of this thesis is to assess the effectiveness of two heat mitigation strategies (i.e., cool roofs and urban forestry) in offsetting climate change impacts on the number of heat stress days experienced by the populations of Vancouver and Victoria, two western Canadian coastal cities facing various environmental complexities (e.g., land-sea breeze). This thesis outlines four objectives to effectively achieve this overarching goal: i) improvement of the temperature observation within the urban canopy, ii) enhancement of the urban micro-climate prediction and climate projection, iii) assessment of climate change impacts on population exposure to heat stress days, iv) assessment of the effectiveness of heat mitigation strategies on population exposure to heat stress.

To achieve the first objective, I propose a user-independent quality control framework tailored to short-term heat events, suitable for crowdsourced air temperature monitoring stations. The proposed quality control framework demonstrates performance comparable to existing quality control methods in the literature for retrieving temperature records. The benefit of the proposed quality control, compared to other methods, is demonstrated using a reference station within the proposed framework. In fact, the proposed framework offers robust user-dependent quality control steps that achieve similar performance in retaining temperature records and stations.

To achieve the second objective, we utilize a high-resolution (i.e., 1 km) Weather Research and Forecasting model coupled with an Urban Canopy Model (WRF-UCM), which enables large-scale investigations of heat mitigation interventions. This model configuration includes an improved land-use representation focused on urban areas, using the mosaic/tiling approach and the local climate zone land-use dataset. The WRF-UCM model performance is validated against a wide range of satellite and ground observations, including quality-controlled crowdsourced air temperature data obtained using the proposed quality framework from the previous objective. The results highlight the importance of vegetation representation across diverse urban areas to capture a more accurate representation of the urban heat island effect and air temperatures.

For the next objective, warming levels are projected to 2058 and 2098 (representing near- and far-future), using the pseudo-global warming method. The SSP2-4.5 and SSP5-8.5 climate change scenarios based on the Coupled Model Intercomparison Project Phase 6 are analyzed. To address uncertainty in climate dynamics, two sets of warmer and colder futures are utilized in the climate projections. The results show that population exposure to heat stress under SSP5-8.5 would be three times higher than under SSP2-4.5 by the end of the century. The results further highlight the importance of mitigating greenhouse gas emissions in reducing population exposure to heat stress, whereas urban population growth is the main contributor to increased population exposure to heat stress.

Ultimately, the fourth objective, which addresses the ultimate goal, is achieved by using the configured WRF-UCM model from the previous objective and modifying the urban parametrizations. I examine the effectiveness of two heat mitigation strategies: cool roofs and urban forestry. Both strategies provide some cooling, yet neither is sufficient to offset meaningfully projected climate change impacts on daily temperature extremes, changes in the number of heat-stress days, and associated population exposure.