Title : Urban heat dynamics and greening optimization in the kurunegala municipal council area: A gis and remote sensing-based approach
Abstract:
The Kurunegala Municipal Council (KMC) area in Sri Lanka has experienced rapid urban expansion over the past decade, resulting in increased impervious surfaces and declining vegetation cover. However, limited research has examined priority areas for Urban Greening (UG) interventions at the Grama Niladhari Division (GND) level. This study analyzes urban heat patterns and identifies suitable locations for UG implementation within KMC using the FAO Green Cities framework. Three objectives were addressed: (1) analyzing Land Surface Temperature (LST) variations and urban heat hotspots from 2015 to 2025; (2) identifying key urban surface drivers; and (3) delineating heat priority zones and developing a GIS-based suitability model to recommend appropriate UG interventions. Multi-temporal Landsat 8 imagery was used to derive LST; hotspots were delineated using Getis-Ord Gi* analysis; Land Use/Land Cover (LULC) maps were generated through Support Vector Machine (SVM) classification, and suitability was assessed using Weighted Linear Combination (WLC). Results indicate that high-temperature areas (>30°C) expanded from 11.5 ha (1.04%) in 2015 to 63.72 ha (5.72%) in 2025. Decadal LST change analysis further reveals that approximately 32.05% of the KMC area experienced a strong warming trend between 2015 and 2025. Persistent hotspots were concentrated in the Kurunegala Town Bazaar, Town Central, Iluppugedara, and South GNDs. Two priority intervention zones were identified: the Kurunegala Town Centre and the Kurunegala Hospital Area. Recommended UG typologies include green facade, landscaped open spaces, with Creeping Fig (Ficus pumila), Cat's claw creeper (Dolichandra unguis-cati) and Karanda Tree (Pongamia pinnata) proposed as suitable species due to their thermal stress tolerance, dry-zone adaptability, local presence and low maintenance requirements. This study demonstrates the potential of a GIS-based decision-support framework for urban heat mitigation and sustainable urban planning in KMC and other rapidly urbanizing secondary cities in Sri Lanka.
Keywords: Urban heat island, land surface temperature, urban greening, remote sensing, Kurunegala Municipal Council.
