Implications of urbanization on the seasonal dynamics and long-term trends in the thermal climate of a city in the Himalayan foothills of India

• Published in: Journal of geovisualization and spatial analysis 2024-12, Vol.8 (2), Article 23
• Main Authors: Singh, Gayatri, Ojha, Piyush Kumar, Sharma, Shivam Kumar, Kumari, Priyanka, Pandey, Alok Kumar, Mishra, Amit Kumar, Kumar, Krishan
• Format: Article
• Language: English
• Subjects: cities; Earth and Environmental Science; Geographical Information Systems/Cartography; Geography; Geology; Landscape/Regional and Urban Planning; Remote Sensing/Photogrammetry; towns; Urban Geography; Urbanism (inc. megacities
• ISSN: 2509-8810; 2509-8829
• DOI: 10.1007/s41651-024-00178-0

This study examines the seasonal and long-term variations in land surface temperature over Dehradun, a rapidly expanding city in the Himalayan region of India. MODIS (Terra and Aqua) satellite data from 2000 to 2019 were utilized to assess (i) seasonal variations in surface urban heat island intensity (SUHII) and (ii) trends in land surface temperature (LST). Positive SUHII was observed over Dehradun throughout the year. However, the magnitude of SUHII varies both diurnally and seasonally, with greater intensity during daytime and the rainy season. Furthermore, our analysis reveals that spatio-temporal variations in LST over Dehradun are significantly influenced by land use-land cover (LULC) variables and elevation. Specifically, open and dense forest areas exert a negative influence, while urban built-up areas have a positive impact on LST. We observed that areas in Dehradun and its surrounding regions that underwent a transition in LULC from agriculture/open forest to urban built-up categories experienced the most significant increase in LST. This rise occurred despite a general warming trend observed in night-time LST across the entire study region, possibly due to global warming. Finally, our study demonstrates an increasing trend in annual cooling degree days, the number of cooling days, and electricity consumption in Dehradun. Therefore, our results suggest that urbanization in Dehradun has resulted in increased warming, which in turn, has steadily contributed to the growth in electricity consumption in the region.