Extreme heat causing health issues - a look at India`s worst heatwave years and the toll they took

New Delhi: Summer arrived early in several parts of India and how! From March itself, a relentless heatwave had mercury soaring in several parts of the country. The India Meteorological Department (IMD) has predicted heatwave conditions in isolated pockets over Madhya Pradesh, Gujarat, Rajasthan, Haryana, Delhi and Uttar Pradesh in the next few days. Even the eastern states of Bihar and Jharkhand are geared up to face extreme heat. 

Heatwaves leading to health complications 

The National Capital Region has been recording maximum temperatures above 40 degrees Celsius over the last few days, much higher than normal. Heatwaves have been a persistent challenge, especially in North India, causing deaths and illness among the populace for years. According to a study published last year, heatwaves have claimed more than 17,000 lives in 50 years in India. The paper, released by some of India’s top meteorologists, said there were 706 heatwave incidents in the country from 1971-2019. 

Heatwave is classified as an extreme weather event (EWE). Between 1971 and 2019, EWEs have killed 1,41,308 people, of which 17,362 or over 12 per cent of the deaths have been caused by heatwaves, the study had said. The maximum heatwave deaths were reported from Andhra Pradesh, Telangana and Odisha. 

Heatwave is also associated with health risks. Some common health conditions arising from heatwaves include dehydration, cramps, exhaustion, heatstroke, gastroenteritis, and food poisoning. The study also noted high mortality due to heatwaves. 

Heatwave in India: Worst years in numbers

According to data firm Statista, 2013 and 2015 were the worst years for India in the last decade when it came to heatwave deaths. While the country recorded 1,433 heatwave deaths in 2013, the number for 2015 was a whopping 2,081!  

Other disastrous years in the last decade were 2012 (729 deaths), 2014 (547 deaths), 2016 (510 deaths) and 2019 (498 deaths). Heatwave deaths dipped in 2020 and 2021, partly due to the lockdown. 

More recently, Maharashtra reported seven heat-related deaths and 59 heatstroke cases over the last few days. With Vidarbha and central Maharashtra reeling under a heatwave, many districts are experiencing maximum temperatures above 40 degrees, several notches above the normal. 

According to Statista, 2010, 2012 and 2019 witnessed the highest number of heatwaves in India in recent years at 254, 189 and 157 days.  “One of the reasons for the increase in heatwaves is global warming associated with increase in greenhouse gases like carbon dioxide, methane, etc. in the atmosphere,” then Earth Sciences minister Harsh Vardhan had said in the Lok Sabha in January 2020. 

Heatwave impact in India: 

Year           Heatwave: Total Days       Heatwave: Total Deaths 

2010           254                                      269 

2011           37                                        12 

2012           189                                      729

2013           93                                       1,433 

2014           128                                     547 

2015           82                                       2,081 

2016          138                                      510

2017          115                                      375 

2018           86                                       33 

2019          157                                     498

2020          42                                        2

(Source: Statista)