Jheelum Basu
According to the World Meteorological Organization (WMO), a heatwave is defined as a period where local excess heat accumulates over a sequence of unusually hot days and nights.
As per IMD, a heatwave is considered if max temperature of in plains reaches at least 40 degree C or more and at least 30 degrees C or more for Hilly regions. IMD says temperatures at which heatwaves are declared differ from place to place
Health risks, economic risks, droughts, wildfires, power shortages and outages and agricultural losses are some of the risks associated with heatwaves
According to IMD, a combination of weather patterns is the primary cause behind the surge in temperatures in including non-monsoon thunderstorms and an active but weakening El Nino climate pattern known for bringing hot and dry weather to Asia
According to researchers, heatwaves occur when there is high pressure in the atmosphere that forces hot air downward and traps it near the ground. This high-pressure system acts like a lock that prevents the hot air from rising, causing the temperature to rise further.
Besides the effects of combined climate patterns, undoubtedly climate change is a vital force responsible for the increased frequency of heatwaves in India.
This year, several parts of the northern region of the country is experienciperatures of over 50 degrees Celsius which is the best example of the drastically shifting climate scenario.
'Nautapa' is defined as the 'nine hottest days' of the year when the sun is directly over Central India leading to a reduction in the distance between the Earth and the sun due to its perpendicular position. This year Nautapa began on May 25 and will continue until June 2.
The IMD has issued a red alert for several states, including Delhi, Haryana, Punjab, Uttar Pradesh, Rajasthan, Madhya Pradesh, and Gujarat as heatwave conditions continue to affect parts of northern and central India.
On Wednesday, parts of Delhi reportedly recorded India's highest ever temperature - of over 52 degrees. However, that still requires further confirmation.
According to the weather office, the heatwave conditions are likely to abate over the next couple of days due to a western disturbance, rainfall, thunderstorms and moist south-westerly winds blowing from the Arabian Sea to northwest India.
To stay protected amid the sweltering heat, a few preventive measures can be taken such as staying hydrated, consuming liquid-rich diet, avoiding outdoor activities, wearing protective clothing etc.