Delhi, including other parts of north India, is reeling under intense heatwave for the past few days. The temperatures in some parts of the national capital soared to 49 degree Celsius on Sunday, nine degrees above normal and recorded as the hottest day of the season so far.
On Sunday, mercury soared to the 49 degrees-mark in Najafgarh and Mungeshpur. Similarly, Gurgaon logged at a high of 48 degrees, highest since 1966. While temperatures soared through the weekend, heat wave conditions are likely to ebb from today, according to the IMD. "Heat wave conditions likely to continue over Northwest & Central India today and decrease in intensity & distribution from tomorrow," IMD said in a tweet on Sunday.
From May 17, there is no heatwave predicted, while thunderstorms over some places are expected to bring respite. "There will be good cloud cover in North Rajasthan, Punjab & Haryana" RK Jenamani, senior scientist, at IMD has said.
Why is Delhi witnessing repeated heatwaves?
Scanty rainfall is being attributed to five heatwaves that Delhi recorded since March this year. In April, Delhi recorded an mean temperature of 40.2 degrees, making it the second hottest April since 1951.
"We have seen western disturbances in March, April and May, but none strong enough to bring substantial rainfall. Most either led to cloudy skies or stronger winds, which can push the maximum temperature by a degree or two, but cannot provide relief," RK Jenamani, scientist at IMD (India Meteorological Department), was quoted as saying by the Hindustan Times.
In April and May, Delhi witnessed only two days of rain, one on April 21 (0.3mm) and May 4 (1.44mm).
Other parts of north India that are reeling under scorching heat include Himachal Pradesh, Haryana, Uttarakhand, Punjab, and Bihar.
Are heatwaves common in India?
The Indian plains are known for hot and dry summers, accompanied with incidents of heatwaves as well. However, this year, the heatwaves, which are expected during May and June, set in early. First heatwave was recorded on March 11.
According to Down To Earth, Rajasthan and Madhya Pradesh are some of the states to be hit hard by the heatwave. By April 24, these two states had 25 heatwave and severe heatwave days.
What is a heatwave?
According to experts, when the temperature in plains crosses 40 degree Celsius, 37 degrees in coastal areas, 30 degrees in mountains, it is called a heatwave. "The IMD declares a heat wave when a place registers a temperature that is 4.5 to 6.4 degree Celsius more than the normal temperature for the region on that day. If the temperature is over 6.4 degrees more than the normal, the IMD declares a 'severe' heat wave," the Centre for Science and Environment said in a report.
Heatwave in other countries
Like India, neighbouring Pakistan too is reeling under heatwave, since the two countries share geographic similarities. More than a billion people in the densely populated region are facing temperatures above 40 degrees.
Power outages triggered by coal shortage and immense pressure on the supply lines has only added to the woes of the people. Crop failures are hinting that the worst is yet to come. The hottest April on record is bound to impact the crops, impacting food security as well as livelihood.
Is there a respite?
According to a report in The Conversation, more intense heatwaves are on the anvil for India. "Assuming the statistical distribution of daily maximum temperatures is broadly the same across the world, statistically a record-breaking heatwave is likely to occur in India at some point. The region has not yet had reason to adapt to such temperatures, so may be particularly vulnerable," the report said.
