​High heat: On India and warming

India’s summers are known to be hot, but this year the high heat has arrived noticeably early. The India Meteorological Department has sounded heat alerts in central and south India, including in Vidarbha, Chhattisgarh, Odisha, Telangana and Kerala. Parts of Andhra Pradesh and Gujarat have also scaled the 40°C mark, with Tamil Nadu and Karnataka not far behind. Local conditions in coastal areas, in particular, could be worse due to humidity and the urban heat island effect. Warmer nights also delay physiological recovery, increasing the local health-care burden. Such temperatures are usually encountered in May-June but have become apparent in April. While pre-monsoon heatwaves are common in India, they are becoming larger and more intense. This year, a lack of western disturbances and thunderstorms, along with lower convective activity, has also done away with natural cooling, with residual effects of the previous El Niño adding to the heat. Persistently high heat is linked to a significantly higher risk of death from cardiovascular causes. Some 247 billion work-hours were lost in 2024 to heat, according to The Lancet Countdown Global Report, with workers in construction and agriculture the most affected. Heat stress is an ongoing concern for farmers during the rabi harvest. Hot weather accelerates crop maturity, threatening food security and feeding inflationary pressure.

Experts have complained that most heat action plans (HAPs) — India’s primary institutional response to heat — focus on emergency response and lack funds for structural interventions such as urban re-greening and mandatory heat-safety legislation for workers in the informal sector. They have thus failed to address underlying vulnerabilities. On April 23, in the Tamil Nadu and West Bengal polls, and Gujarat and Maharashtra by-elections, lakhs of electors had to brave the heat. Concerns about voter turnout in the heat prompted the Election Commission of India to keep polling booths open longer during the 2024 general election; such reactive measures alone will not suffice this year. If warming continues along current trajectories, more than a few parts of India will begin approaching human survivability limits. HAPs desperately need sufficient, long-term funding while public systems must roll out mobile health units and doorstep delivery of essential services during peak heat to reduce the income penalties that deter access. Colombia has convened a coalition of roughly 50 countries to explore a faster transition away from fossil fuels in a parallel ‘climate conference’. India should join it, not least because of the greater access to climate adaptation finance it could afford.