The Capital is staring at a heat emergency

Delhi will remember the summer of 2022 as one that broke many weather records. After extreme temperatures and back-to-back heatwave days, the Capital’s heat index touched 53 degrees on Tuesday, and the wet-bulb temperature, 33.7 degrees (the highest this year). The heat index is a function of maximum temperature and humidity, calculated in the shade. The wet-bulb temperature takes into account maximum temperature, wind speed, humidity, and solar radiation, calculated under direct sunlight. According to the India Meteorological Department, moisture-laden easterly winds are keeping humidity levels at 45%-74%.

The high heat index and wet-bulb temperatures can have adverse effects; at wet-bulb temperatures of 32°C, even fit and acclimatised people can’t work; at 35°C, the same people sitting in the shade die within six hours. Scientists warn that the climate crisis is making high wet-bulb temperatures more likely. If this is the future, India is staring at a crisis. This will have a countrywide impact. But the economically weaker states will be hit the hardest because a large demographic depends on daily wage work.

Policy gaps must be addressed. First, redefine heatwaves to include humidity; second, set up a system for proper reporting of heat-related deaths (90% of such deaths are not reported due to technical difficulties in diagnosing them); third, establish an institution legally bound to make data available; and fourth, make heat-related illnesses “notifiable” diseases and list them as a disaster by the National Disaster Management Authority so that heat victims can qualify for relief assistance. The heat emergency must be tackled before it gets out of control.