Tamil Nadu's Heat Crisis: Either Build Sustainably Or Burn

TN faces compounding challenges: recurring droughts, erratic rainfall, cyclones, floods, sea level rise, and increasingly, heat waves. The IMD recorded 591 disastrous heatwave days across TN's districts between 1969 and 2021, where at least one heat-related fatality was reported per day. As per Anna University's Centre for Climate Change and Disaster Management, thermal discomfort days are projected to rise from 107 days per year (1985-2014) to 150 days per year by 2050

- SV KRISHNA CHAITANYA @Chennai

S Tamil Nadu continues its breakneck urbanisation, a new decadal study commissioned by the State Planning Commission (SPC) has sounded alarm bells over rising land surface temperatures (LST) and worsening heat stress across the state. Titled "Urban Growth and Thermal Stress: A Decadal Assessment of Built-Up Area and Climate Interactions in Tamil Nadu," the report reveals how unregulated urban expansion has created dangerous heat islands, strained infrastructure, and intensified ecological degradation in the last two decades.

The study, which integrates high-resolution spatial data from MODIS LST, ERA5 air temperature records, and building footprint changes from 1985 to 2015, maps heat exposure at the block-level for all 389 blocks across Tamil Nadu. The results show 94 blocks have witnessed a steep rise in heat over the past 40 years, while 64 blocks currently suffer from temperatures well above the state average. Particularly vulnerable are 25 blocks — including those in Chennai, Karur, and Ramanathapuram — which fall into both categories, making them high-risk zones for future climate and health.