Assessing Urban Green Spaces' Role in Mitigating Heat Island Effects

Thesis Abstract

Urban areas worldwide are experiencing increasing heat intensities due to rapid urbanization and climate change, resulting in the exacerbation of the urban heat island (UHI) effect that adversely affects public health, energy consumption, and overall livability. This study aims to systematically assess the effectiveness of urban green spaces in mitigating UHI effects within a dense metropolitan context. The specific objectives include quantifying surface and air temperature variations in relation to green space distribution, evaluating residents’ perceptions of thermal comfort, and determining the relationship between green space attributes and UHI intensity. The study adopts a mixed-methods research design, integrating quantitative spatial analysis with qualitative assessment of community perceptions. The quantitative component involves a cross-sectional spatial analysis using remote sensing data and ground-based temperature sensors across four distinct neighborhoods. A total of 200 sampling points will be established within areas characterized by varying proportions of green cover, identified through high-resolution satellite imagery. Ground temperature data will be collected over a three-month summer period using 50 calibrated temperature loggers, while land surface temperature (LST) will be derived from Landsat 8 imagery processed through ENVI software. Concurrently, air temperature and relative humidity will be measured using portable weather stations. Qualitative data will be obtained via structured interviews and focus group discussions with 150 residents selected through stratified random sampling to explore perceptions of thermal comfort and green space usability. Data analysis will employ geospatial techniques, including spatial autocorrelation and hotspot analysis, to identify temperature anomalies and correlations with green cover. Multiple regression analysis will be conducted to quantify the influence of green space attributes—such as size, type, and vegetation density—on temperature reduction. Thematic analysis of qualitative data will uncover community perceptions and adaptive behaviors related to green spaces. The study is grounded theoretically in the Biophysical Climate Regulation Theory and the Social-Ecological Resilience Framework, which contextualize the tangible and intangible benefits of green infrastructure. Expected findings anticipate a statistically significant inverse relationship between green space extent and temperature anomalies, with larger and densely vegetated areas demonstrating greater cooling effects. It is also expected that residents’ perceptions will reflect increased thermal comfort and enhanced social cohesion in areas with accessible green spaces. The analysis will reveal threshold levels of green cover necessary for meaningful UHI mitigation, contributing empirical evidence to the ongoing debate on urban planning and climate resilience. This research contributes to the existing body of knowledge by providing a nuanced understanding of the spatial and social dimensions of green space effectiveness in heat mitigation. It bridges the gap between remote sensing data and community-based insights, offering practical guidelines for urban planners and policymakers aiming to optimize green infrastructure for climate adaptation. The study concludes that strategic allocation and enhancement of green spaces can substantially reduce UHI effects and improve urban livability. Recommendations include adopting integrated green space planning that prioritizes increasing vegetation density in high-temperature zones, implementing community engagement programs to promote green space usage, and establishing policies for maintaining and expanding urban green infrastructure. Future research should explore longitudinal impacts of green space interventions and assess the cost-benefit analysis of various green investments. Overall, the study underscores the vital role of urban green spaces as nature-based solutions for climate resilience, emphasizing the need for context-specific strategies that enhance both ecological and social resilience in urban environments.