The Silent Killer: As Heat Wave Engulfs Northern India, Here’s Why It’s Deadly And How To Minimise The Damage

A scorching heatwave has swept northern India.

On Tuesday (26 May), North India and South Pakistan were reported to be the hottest region of the world. Delhi reportedly recorded the hottest temperature in May in 18 years.

In New Delhi, Palam area recorded 47.6 degree Celsius, six notches above the normal. Churu in Rajasthan reached 50 degree Celsius. In last ten years, only one other time the temperature in Churu breached the 50 degree Celsius mark.

In Uttar Pradesh, Allahabad turned out to be the hottest place at 47.1 degrees Celsius. Hisar topped in Haryana at 48 degrees Celsius.

In Punjab, Patiala recorded a high of 44.7 degrees Celsius. Ahmedabad in Gujarat recorded 43.7 degrees Celsius.

Apart from these states, hot weather conditions also prevail over Chhattisgarh, Gujarat, Maharashtra, Telangana, Bihar, Jharkhand and interior regions of Odisha and Andhra Pradesh.

What is a heatwave?

Heatwave is a period of excessively hot weather when the temperatures higher than the normal for the region in the season. Pollution, urban heat island effect etc exacerbate the heatwave in the urban areas.

Those who are required to work outside, like farmers, street vendors, traffic policement etc. are the most affected.

Typically, in India, heatwaves occur between March and June. They can extend till July in some rare cases.

Heat waves can cause dehydration, cramps and exhaustion:

• Heat Cramps: Ederna (swelling) and Syncope (fainting) generally accompanied by fever below 39 degree Celsius
• Heat Exhaustion: fatigue, weakness, dizziness, headache, nausea, vomiting, muscle cramps and sweating
• Heat Stroke: body temperatures of 40 degree Celsius or more along with delirium, seizures or coma, a potentially fatal condition

Heat waves can be dangerous, even life-threatening.

According to WHO, between 1998 and 2017, more than 166 000 people died due to heatwaves, including more than 70 000 who died during the 2003 heatwave in Europe.

In India, heatwaves are the third biggest natural cause of deaths, having killed over 6,000 people since 2010.

The actual number must be higher because only the deaths due to heat-stroke and heat exhaustion are recorded, but overheating of a human body can also can lead to organ failure, stroke, and cardiac arrest.

Heat wave also cause a potential decline in output and productivity. Thanks to climate change, the heat wave events are predicated to increase in frequency and intensity in the future. In India, 23 states were affected in 2019, up from 19 in 2018.

Heatwave can also cause forest fires. It can cause roads and highways to buckle and melt, water lines to burst, and power transformers to detonate, causing fires.

Precaution and mitigation

The National Disaster Management Authority (NDMA) provides Heat Wave safety tips which include drinking plenty of water, avoiding going outside in the sun, providing shelter, shade and water to animals.

ORS or salt-sugar solution should be given to both family members and domestic animals. Medical help should be sought immediately as heat stroke can be fatal if not treated in time.

NDMA also has a Heat Action Plan that provides a framework to the states to respond to heat wave conditions. However, not many have implemented these guidelines properly.

The guidelines include:

• early warning system
• training health care professionals
• improving community outreach to alert people
• setting up temporary shelters
• improving water delivery systems.

Apart from this, afforestation (as trees have a natural cooling effect on the surroundings), restoration of wetlands, targeted intervention based on hot-spot identification, bottom-up feedback systems, public awareness and data collection will go a long way.

Kuldeep Srivastava, Head of IMD's Regional Weather Forecasting Centre, has said that there will be a respite from the high temperatures from Thursday night (28 May) as western disturbance will affect northwest India and easterly winds will prevail in the lower levels.