Assessing urban thermal field variance and surface urban heat island effects. An Ecological Study in Malakand Division, Pakistan

This study examines the ecological and thermal impacts of urbanization in Malakand Division, Pakistan, from 2003 to 2023, focusing on the Surface Urban Heat Island (SUHI) effect and human thermal comfort (HTC). Using multi-temporal Landsat (5 and 8) imagery, Land Surface Temperature (LST) data, and the Urban Thermal Field Variance Index (UTFVI), we analyze urban expansion, land-use changes, and their thermal implications. Results show significant urban growth, with built-up areas increasing from 11,773.5 km² to 12,519.09 km², while vegetative land decreased by 7.5%. The average LST rose by 3.67°C, and UHI intensity increased from 15.96% in 2003 to 19.08% in 2023. Spatial analysis highlights higher LST and UTFVI values in urbanized and transition zones, indicating worsening thermal conditions. These findings underscore the need for sustainable urban planning to mitigate UHI effects, enhance HTC, and promote green space development. This research provides critical insights for urban planners and policymakers in Malakand Division and other rapidly urbanizing regions