After the flood fury that wreaked its anger on nearly 2 crore people across 14 States, the southwest monsoon finally began retreating on Wednesday. The monsoon withdrawal will be complete by October 20. The season ended with a 10 per cent higher rainfall than the long term average.
According to India Meteorological Department (IMD), this is the longest delayed withdrawal of monsoon. “The most delayed withdrawal in the past years was recorded in 1961 (on October 1), followed by September 30, 2007,” the IMD pointed out. The normal date of the withdrawal is September 1.
“The withdrawal started from Kapurthala, Ambala, Karnal and Churu on Wednesday. In view of the persistence of an anti-cyclonic circulation in the lower tropospheric level over northwest India, gradual reduction in moisture in the lower and mid tropospheric levels and reduction in rainfall, the southwest monsoon has withdrawn from some parts of Punjab, Haryana and north Rajasthan today, October 9, 2019, as against the normal date of September 1,” the IMD said.
The excess rain this year has not only flooded several cities and towns but are also expected to cause extensive damage to standing kharif crops in States such as Madhya Pradesh, Maharashtra, West Bengal, Rajasthan, Bihar and eastern Uttar Pradesh.
As per data of flood situation reported by the Ministry of Home Affairs, over 1,700 people have died and crops in nearly 13 lakh hectare in these 14 States have been destroyed.
The delayed onset of the monsoons initially meant a rainfall deficit of 33 percent in June, but the season ended with a 10 per cent higher rainfall than the long term average. On the flip side, longer monsoon could also restock reservoirs and help replenish ground water, helping assuage water shortages in pockets of the country of 1.3 billion people and boosting production of rabi crops.
The IMD said that the moisture level in the atmosphere will reduce gradually in the lower levels over the next two days, giving way to dry and cooler air from across the border to fill the lower levels, suppressing rainfall.
“This would set up the right conditions for the monsoon to exit from parts of North-West India initially, before the withdrawal line covers more areas over West, North-West, Central and East India. By the time the line crosses Central India, conditions would have evolved over the Bay of Bengal, Peninsular India and the Arabian Sea for the retreating monsoon (North-East monsoon),” IMD said.
The monsoon, meanwhile, has seen a number of other records being made this year, the IMD said in a detailed review at the end of what has been an exceptionally productive season.
After 1994, (110 per cent of long-period average, or the LPA), the rainfall received during the just concluded 2019 season is the highest seasonal rainfall received by the country as a whole.
(The LPA is calculated on the basis of the mean rainfall during the four-month monsoon season over the 50-year period from 1951-2010. It works out to an average of 89 cm for the country as a whole).
During 18 of the last 19 years (2001-2019), North-East India has received seasonal rainfall less than LPA with an exception of 2007 (110 of of LPA), the IMD observed.
This indicates that the seasonal rainfall over North-East India is passing through a below normal epoch like it was during the early 1950s to mid-1980s.
