Heat waves demand urgent action

The country is reeling under a widespread heat wave. The surge in temperatures across northern, central and eastern India suggests a broader atmospheric phenomenon rather than isolated regional events. One explanation is the ‘heat dome’ — a high-pressure system in which warm air is pushed downward, compressing and heating air near the ground. The trapped air mass prevents cloud formation and, combined with intense sunlight, drives temperatures to dangerous levels for consecutive days.

Urban areas worsen the impact: concrete and asphalt trap heat, raising night-time temperatures. Lack of moisture, sparse pre-monsoon showers and dry soil further intensify the heat. Hot, dry winds sweeping across north India have also suppressed cloud formation and rainfall. The rising frequency and intensity of such events point to fossil fuel-driven climate change.

The National Oceanic and Atmospheric Administration (NOAA) has predicted that El Niño is likely to emerge between June and August, with a 61 per cent chance of it becoming a strong ‘Super El Niño’. This weather pattern, part of the El Niño-Southern Oscillation, is caused by the weakening of trade winds over the tropical Pacific, allowing warm waters to shift eastwards towards South America. The result is extreme weather—droughts, floods, heat, and declining sea ice—across regions. Warmer sea surface temperatures often translate into hotter summers in parts of Africa, Europe, and India.

The India Meteorological Department (IMD) has endorsed NOAA’s forecast, reiterating the strong link between Pacific Ocean conditions and India’s June-September rainfall. A weakened monsoon could have wide-ranging consequences: lower agriculture productivity, rising inflation and slower GDP growth.

Even before El Niño sets in, large parts of north and central India are experiencing extreme heat, while pockets in the south and north-east see moisture inflows and thunderstorm —a sign of growing climate variability. 

Bengaluru, once an ‘air-conditioned’ city, now increasingly relies on artificial cooling as temperatures rise. The IMD data indicate a 1.5 degrees Celsius increase in minimum temperature during April and May, pushing households to use air-conditioning even at night — often powered by fossil fuels, creating a vicious cycle. While Bengaluru’s maximum temperature hovers around 36 degrees Celsius, the Kalyana Karnataka region faces 42-44 degrees Celsius. Coastal regions, though below 40 degrees Celsius, suffer from high humidity and dehydration, making conditions harsher.

For gig workers and farmers, working in such conditions is hazardous, increasing the risk of heatstroke. High humidity accelerates fluid and electrolyte loss, leading to lightheadedness; reduces blood circulation to vital organs; and heightens health risks. 

Cities like Bengaluru, where shade trees of native species grow luxuriantly, have experienced unprecedented growth without adequate provision for replenishing their tree cover. Greater Bengaluru needs more than a hundred tree parks like Lal Bagh and Cubbon Park. The space on either side of roads in the city is either tiled or asphalted, with no scope for greenery. Even new layouts lack adequate space for planting trees. Besides, unbuilt areas covered with concrete or tiles leave no scope for rainwater to percolate and charge the underground aquifers. Water harvesting structures are mostly defunct. 

Apart from large tree groves, urban water bodies should also be rejuvenated to provide respite from heat. Karnataka, in its recent Budget, has made provisions for tree parks in all districts and for planting 75,000 ha of degraded forest lands in the Kalyana Karnataka region. This Budget statement appears misplaced as the state government proposes to divert good-quality Western Ghats forests for projects like the Hubballi-Ankola rail line and Saravathi pump storage. The success rate of tree-planting initiatives in dry regions is poor, and the rate of growth is not even 1 per cent of the rate of plantation growth in the Malnad region. Sacrificing natural forests in Malnad and focusing on afforestation in dry zones does not amount to much. Hundreds of streams and rivers originate from the Western Ghats, and the ecological services it provides to the entire peninsular India in terms of rains, flowing water and oxygen are unmeasurable. 

With the ongoing heat wave likely to be followed by El Niño, the state government must closely monitor reservoir levels to manage irrigation, power and urban water supply. The IMD should continue regular forecasts. Price caps on water tankers may be needed in emergencies. Forest fire prevention must be strengthened, including, if required, the use of firefighting helicopters. 

(The writer is the former Head of Forest Force, Karnataka)

Disclaimer: The views expressed above are the author's own. They do not necessarily reflect the views of DH.