Unplanned urbanization drives heat stress in T’puram district

T'puram: At a time when the mercury level soars, a recent study by the geography department at University College has revealed alarming trends in land use and land cover (LU/LC) changes in the capital city and its surrounding areas, highlighting the environmental impact of unplanned urban expansion.
The research points to a significant rise in land surface temperature (LST) and the urban heat island (UHI) effect, driven largely by the transformation of green spaces and open areas into built-up regions over the past three decades. Between 1988 and 2022, built-up areas in Thiruvananthapuram increased by a staggering 118.46% while vegetation, open areas and water bodies declined by 24.27%, 64.31% and 43.88%, respectively.
The rapid change is linked to the city's growing population and development pressures, especially as Thiruvananthapuram serves as the administrative and IT hub of Kerala, with strong connectivity through road, rail, air and sea. The study recorded a rise in LST by 4.84ºC from 1988 to 2022 with the mean LST over the 34-year period increasing from 26.96ºC to 28.52ºC.
Since 2000, the city showed clear signs of the UHI effect, particularly in densely built-up zones. In response, the researchers proposed a heat stress vulnerability index (HSVI) using the analytic hierarchy process (AHP) method to identify areas at risk. The HSVI results classify 5.19% of the area as very highly vulnerable, 8.87% as highly vulnerable, 17.88% as moderately vulnerable and the remaining as low or very low vulnerable, finds the study carried out by research associates RS Anupriya and TA Rubeena.
Notably, the most heat-stressed regions are concentrated in the central and north-western parts of the city. The study, which covered Thiruvananthapuram corporation and 18 adjoining panchayats with a population of over 1.5 million, emphasises the urgent need for eco-friendly development. It calls for increased green spaces and sustainable urban planning to mitigate rising temperatures and the UHI effect. Importantly, the study stresses that long-term change can only be achieved through coordinated govt policies and active community participation.