The devastating floods in Kerala in August were an outcome of a chain of extreme weather events that climate change has triggered in India, the Director General of Indian Meteorological Department, KJ Ramesh, told NDTV in an exclusive interview.
"Country has witnessed the evidence of significant changes in extreme weather events and the extreme rainfall in Kerala happened because of these changes in India's climate. In terms of rainfall, it was exceptionally high," Mr Ramesh said.
He said the extreme rainfall happened at a time when water level in the main reservoirs of Kerala was already very high towards the end of July.
The two heavy spells of rainfall in August -- first between August 8 and 10, and then between August 14 and 17 -- forced the administration to release water from the dams as they could not hold more water.
Because of the topography of Kerala with hills and slopes, the water from dams went downstream in heavy speed, leading to flash floods and heavy inundation in many areas.
The top weather official said India must analyse the lessons and data it has gathered from the Kerala foods. He said a new technology has been developed to study the rise of water level in rivers and reservoirs because of heavy rainfall, which will help the state governments to effectively monitor the impact of rainfall.
"The topography of every river basin is different... the slope characteristics and their length is different and so this new framework will have to be customised according to the ground reality in every state. This must be implemented in every state. One model won't work in every river basin... The centre will have to work with the states to implement this new framework," Mr Ramesh told NDTV.
Studies done by the Indian Meteorological Department or IMD has shown significant changes in the rainfall pattern in India in the last few decades.
"The frequency of daily rainfall up to 10-15 cm has significantly increased since 1947, while the intensity of low rainfall of up to 5 cm has decreased in India. This has happened because of global warming," Mr Ramesh said.
Significant changes have also been observed in the frequency of cyclones and hurricanes across the world, he said. "At the global level, 10 cyclones used to be recorded on an average. Now their average number has increased to 18 in a year. Nature magazine has published a research paper recently on this issue. Though the frequency of cyclones in India has not increased in the Bay of Bengal or the Arabian Sea, their intensity has definitely increased," Mr Ramesh said.
Over 400 people lost their lives and thousands of homes were destroyed in the unprecedented floods in Kerala in August.