india

Updated: Aug 17, 2018 09:09 IST

Kerala is among the states that receive the highest monsoon rainfall, but sustained low-pressure conditions over India’s western coast this year have caused the flooding in the state, India Meteorological Department officials said. Different studies, however, have found that climate change and deforestation were the main causes of an increase in rainfall.

Environmental scientist Dr VS Vijayan, a member of the expert panel on the Western Ghats, said Kerala was going through a man-made disaster. He said the impact should have been limited if the Gadgil committee report, aimed at protecting ecologically-fragile mountain ranges, was implemented.

He attributed the floods to human incursions and unscientific developmental activities in ecologically-sensitive areas.

“This was waiting to happen. Insensible use of land, soil and rocks led to this deluge. Landslips and flash floods happened in areas that witnessed widespread human incursions. I hope everyone will learn a lesson from this. Due to climate change, such tragedies are bound to increase. Nobody can stop rains or control floods. But we can take measures to lower the intensity of such impacts,” he said.

A 2014 Indian Institute of Tropical Meteorology study based on rainfall data since 1900 had said that intensity of the monsoon rains was increasing and one of the factors for it was global warming. Another 2017 IIT Bombay study held deforestation mainly responsible for the phenomenon.

In 2010, the Centre set up an expert panel under Gadgil following widespread concern that the Western Ghats, which plays a key role in breaking rain clouds over the subcontinent, was shrinking due to human incursions.

When all six states falling under the Ghat region (Kerala, Tamil Nadu, Karnataka, Goa, Maharashtra and Gujarat) opposed the recommendations , another committee was constituted under former ISRO chief Kasturirangan.

Kasturirangan had made some changes in the zonal classification and reduced ecologically sensitive areas to 37% from 64%. But still many states opposed it saying people living in the fringe areas of Ghats will be thrown out of their habitat if the report was implemented.

IMD’s senior scientist Mrutyunjay Mohapatra said the lowpressure situation of different levels was persisting over the Kerala-Karnataka coast for the last fortnight. “The low pressure in the Arabian Sea attracts the southwesterly winds from the high-pressure Bay of Bengal, gets concentrated over the region due to high moisture in the air and causes rain once it hits the Western Ghats,” he said.

Mohapatra said the two major low-pressure situations happened on August 7 and 13, causing heavy downpour in the region, apart from several other small similar situations since July last week. The region -- Kerala, coastal Karnataka and KonkanGoa -- has received 7,158 mm of rainfall, which was about 46% of the total rainfall received in rest of India during this monsoon .

The IMD on Thursday said a low pressure system persisted off the Kerala coast over the Lakshadweep Islands, causing an eddying of the water vapour currents at different levels of the atmosphere leading to precipitation. More rain is predicted in the coming days.

An Indian Institute of Technology (IIT), Bombay, study in May 2018 showed that evapotranspiration from the vegetation over the Western Ghats accounts for half of the total rainfall in southern peninsular India during monsoon months. “The years there is less moisture in the Western Ghats, the region sees deficient rainfall,” the study said.