Environment

This June may be second-most rain deficient in 7 years

This comes when the country has already been experiencing an extended dry spell since the end of last year’s monsoon season

 
By Akshit Sangomla
Last Updated: Thursday 27 June 2019
Monsoon was arrested in Kerala, Tamil Nadu and Karnataka till June 21. Photo: Getty Images
Photo: Getty Images Photo: Getty Images

The southwest monsoon has advanced further north covering most parts of the Indian sub continent, except the northern and north-western regions, but its overall performance is still dismal.

“During the rest of the June days, the daily average rains will be below normal, but the deficiency will be to the tune of 10 to 20 per cent only and not as high as it was in the past days. So, by the end of June, the total deficiency will drop to around 33 per cent,” said a report by Skymet Weather Services, a private weather forecasting agency.

If that is indeed the case then this June will have recorded the second-lowest rainfall in the past seven years after the 42 per cent deficit in 2014, breaking 2012’s record of 30 per cent, according to data from the India Meteorological Department (IMD).

Moreover, in the past 146 years, whenever the deficit rainfall in June has been more than 30 per cent it has either led to a below normal monsoon or drought, except in three years — 1923, 1924 and 1926, according to IMD.

The monsoon had a poor beginning with a delayed onset and slow progress, which means June 2019 will record deficient rainfall.

The initial delay in the onset could have been because of prevailing weak El Niño conditions in the equatorial Pacific Ocean. The El Niño caused unusual heating of the sea surface resulting in disruption of regular weather systems over the Indian subcontinent.

The slow progress of the monsoon winds was brought about by the development, propagation and dissipation of very severe Cyclone Vayu in the Arabian Sea over nine days from June 9 to June 17.

The winds of the cyclone disrupted the regular trade winds in the region, which are the carriers of monsoon. This kept the monsoon arrested in Kerala, Tamil Nadu and Karnataka till June 21.

The monsoon winds have become weaker in the last few decades leading to decrease in overall rainfall on the Indian sub-continent, according to a research paper published by scientists from Harvard University, Peking University and Chinese Meteorological Administration in the journal Science Advances in December 2018.

Significant warming in the Indian Ocean has decreased the temperature difference between the land and the sea which is the main trigger for the flow of monsoon winds, according to the study. But more research is required to establish how exactly these essential wind patterns are changing.

Different regions in India are suffering from the lack of rainfall leading to a lacklustre sowing season for farmers. The country has received 36 per cent less rainfall than normal since June 1 which is considered as the beginning of monsoon season.

Of the 36 states and Union territories, 31 are facing a rainfall deficit greater than 25 per cent. Further, 16 have a rainfall deficit of above 40 per cent.

Only Jammu and Kashmir, Sikkim and Rajasthan have recorded an excess rainfall of 25, 15 and 7 per cent respectively. Among the states, Manipur, Jharkhand and Maharashtra are suffering from the largest deficits of 61, 60 and 57 per cent respectively.

This comes when the country has already been experiencing an extended dry spell since the end of last year’s monsoon season. September had recorded a deficit rainfall of 23.5 per cent. In the post monsoon season rains were again deficient by 43.9 per cent.

The winter months of January and February saw some rainfall in the north western parts of the country, mainly brought in by the western disturbances coming from the Mediterranean region. But then the rains eluded again with the pre-monsoon season this year recording a deficit of 25 per cent, the lowest in 65 years.

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