Extreme rainfall events on the rise, says study

Thiruvananthapuram: Extreme rainfall events over central India are increasing, according to a study conducted by a team of scientists at the Centre for Climate Change Research, Indian Institute of Tropical Meteorology, Pune. What used to be two widespread extreme events a year in the 1950s is six per year now. The paper contrasts this with the fact that the mean rainfall in the region has been decreasing. “This  implies that the dry spells in the region may be decreasing,” it says.

As per their paper published in ‘Nature Communications’ on October 3, Arabian Sea is a major contributor to the extreme events. Dr Roxy Mathew Koll, who led the team, told DC, “warming over the Arabian sea has resulted in huge fluctuations in the monsoon winds, which result in occasional surges or moisture transport lasting two or three days.” The warming is due to human activities, but not necessarily local activities, he says. He ascribes it to large-scale increase in carbon emissions.

“The carbon dioxide in the air will remain for centuries and we might be seeing more extremes in the future. What we can do is to stop it from accelerating further. For that,  we need to collectively embrace cleaner energy resources and sustainable development,” he says. The silver lining is that IMD is able to predict extreme events in advance of 5-6 days, according to Dr Roxy Mathew Koll. “Even the recent Mumbai floods were predicted in advance by IMD. What we need is to link it to a proper flood forecasting system with an early warning facility,” he says. The analysis is based on rainfall data from India Meteorological Data (IMD) during 1950-2015. As per International Disaster Database, there have been 268 reported flooding events in India over 1950-2015. The paper says most of these events occurred over central India.