Pune: The Indian Summer Monsoon, popularly known as Southwest Monsoon, is likely to reach Central India between June 11 and 19, according to the new forecast method developed at the Potsdam Institute for Climate Impact Research (PIK), Germany.
The monsoon onset date is of crucial importance for hundreds of millions of people in India. Climate change affects monsoon variability and hence makes accurate forecasting even more important.
The unique forecast had been developed specially for the central part of India where, before, early forecasting has never been made. Elena Surovyatkina, a professor from PIK, leads the forecasts analysis team.
The approach is based on analysis of observational data and allows predicting the monsoon onset date 40 days in advance. According to Surovyatkina, the Southwest Monsoon is likely to set on or around June 18 with a probability of 73 per cent.
While talking about her observation in an email, Surovyatkina said their team found a new important property of the Southwest Monsoon.
“There are two tipping elements in a spatial-temporal organisation of monsoon. One is located in eastern ghats and another one is in North Pakistan. An equalisation of temperatures and humidity in these two tipping elements mark a critical transition to the monsoon. The situation is mimicked at the withdrawal date of monsoon. The same phenomenon has happened in 75 per cent years between 1957 and 2015. Our team has used this property for prediction of the onset and withdrawal of monsoon,” said Surovyatkina.
Surovyatkina said that in 2016 and 2017, she successfully predicted the onset and withdrawal dates of the Southwest Monsoon over the central parts of India.
“I delivered a forecast for the onset of monsoon on May 8, that is 40 days in advance, and a forecast of monsoon withdrawal date on July 27, that is 70 days in advance. Hence, we proved that such early prediction of monsoon timing is possible,” said Surovyatkina.
Same accuracy, but with A different approach
The region of the forecast is located in the central part of India in the area of the eastern ghats, namely in the southeastern part of Maharashtra, the western part of Chhattisgarh and the northern part of Telangana.
Elena Surovyatkina, PIK professor, said the approach of their team and that of the India Meteorological Department (IMD) are different and both have the same accuracy.
“The approaches have two different locations, Kerala in the case of IMD and the Eastern Ghats in our case and both the institutes are using different kind of data,” Surovyatkina said.
She said these approaches are complementary, and will help improve predictability of monsoon onset and its propagation through the Indian subcontinent.