Hot Indian summer likely to slow down coronavirus spread

Vibha Sharma

Tribune News Service

New Delhi, March 28

As scientists work on the link between temperatures and the deadly coronavirus, the good news is that India appears to be heading towards a particularly hot summer this year.

According to the IMD, due to ongoing rainfall/thunderstorm activities, temperatures below normal by 2 to 4 degree C were recorded over most parts of the country this week. However, the mercury is set to rise from the first week of April.

Thereafter, the only way it should move is up, say weather experts.  

This is something the government and scientists are also hoping — that after the 21-day lockdown ends by mid-April a full blown summer will be in place, slowing down the spread of the COVID-19 virus.

The Western Disturbance that brought widespread rains and thundershowers to plains, snow in hills and pulled down temperatures earlier this week is passing off. Though another one is expected around March 30, weather expert Mahesh Palawat does not expect it to be as intense or pull down the temperatures much.

Temperatures are rising and the trend is expected to continue through April, bringing them to the range of late 30 degrees C and early 40 degree C by mid-April, he says.

Though the humidity levels in north will remain relatively low, around the coasts it will be both hot and humid, factors that have been known to work against viruses of corona family.

Some studies have suggested the new coronavirus will follow the “marked seasonality” shown by its genetic cousins prevailing among humans since centuries. In other words the family is generally more volatile between December and April. This has given a good reason to believe that by May/June the impact of the virus will be much less than what it is at present.

Meanwhile, a preliminary study of COVID-19 progression trends by Massachusetts Institute of Technology (MIT) researchers have shown that much lesser cases were seen in hotter zones.

In an early trends research on the pandemic, Qasim Bukhari and Yusuf Jameel of MIT concluded that more research should be done conclusively establish the impact of higher temperatures and humidity on disease trends.

MIT study indicates that 90 per cent of the transmissions until March 22 occurred in regions with temperature between 3 degree C and 17 degree C and absolute humidity between 4 to 9g/m3 (grams per cubic metre).

“The total number of cases in countries with mean January-February-early March temperature more than 18 degree C and absolute humidity of over 9 g/m3 is less than 6 per cent,” say the authors.

“Wherever the temperatures were colder, the number of the cases started increasing quickly. You see this in Europe, even though the health care there is among the world’s best,” they were quoted as saying.

IMD forecast

(Week 1) till April 1: A Western Disturbance is likely to affect Western Himalayan Region from March 30. Scattered to fairly widespread rainfall/snowfall (with isolated heavy falls over Jammu and Kashmir) expected over Western Himalayan region between March 31 to April 1; isolated to scattered rain/thundershowers likely over northeast India, central India and southern peninsula.  

(Week 2) Between April 2 and 8: Near normal to below rainfall likely over Kerala, Western Himalayan Region and northeastern states and Andaman and Nicobar Islands with mainly dry weather likely over rest parts of the country

Temperatures: Due to ongoing rainfall/thunderstorm in Week 1 temperatures below normal by 2-4 degree C over most parts of the country activity over many parts of the country. During week 2, rise in maximum temperatures. However these are likely to below normal by 1-2 degree C over Central and adjoining east and south Peninsular India.