Climate change may bring flooding and farming woes to Kolkata & Bengal, fear experts – Times of India

KOLKATA: Monsoon mayhem, coupled with an increased frequency of other extreme weather events — as a direct result of climate change — will most likely cause adverse agricultural outcomes and uncontrolled waterlogging across Bengal and Kolkata in the near future unless immediate steps are taken to cut greenhouse emissions, experts have said.
Global temperatures are expected to reach or exceed 1.5°C of warming over the next 20 years under all scenarios in the latest report from the Intergovernmental Panel on Climate Change (IPCC), released on Monday, which the UN has termed a “code red for humanity”.

The report suggests that the Himalayan region, along with the eastern coast of India, is especially vulnerable to the effects of climate change. The frequency of the formation of very tall columns of cloud (often over 10km tall) holds ominous predicaments for Kolkata and rest of Bengal, especially for agriculture schedules and crop production.
AVM G P Sharma, president, meteorology and climate change, Skymet Weather, explains that with global warming intensifying, the Indian monsoon has already started to become erratic. And scientists have warned that the quantity of rain would increase further with temperature increase. “We are not even halfway through the season yet, and we have already achieved the seasonal rainfall target,” Sharma says.
‘Sea change in monsoon season pattern’
“Weather sensitivities are on the rise, be it the intensity or frequency of cloudbursts, landslides, heavy rainfall, cyclones or other phenomenon. Monsoon has become erratic and we are witnessing a sea change in the monsoon season pattern, once considered to be the most stable.” Climate change, he adds, “is the reality of this moment. It is no longer the domain of weather experts, and requires a multidisciplinary or multispeciality focus, which needs integration among all stakeholders.”
According to a recent study by Potsdam Institute for Climate Impact Research, climate change is making the Indian monsoon season more chaotic. For every degree Celsius of warming, monsoon rainfall will likely increase by about 5%, the report says, adding that global warming is increasing the quantity of monsoon rainfall in India even more than previously thought.
Experts say the city will get flooded more frequently, and for greater durations. “Climate change has caused unusually concentrated rainfall and delayed monsoon,” says West Bengal Pollution Control Board chairman Kalyan Rudra, who has done century-scale analyses of rainfall in Bengal and the city. “This dual effect of climate change has had, and will have, a far-reaching impact.”
Highly concentrated rainfall causes more run-offs and less infiltration of water, he says. “The groundwater of the city and elsewhere in Bengal is dangerously depleted. The recharging of groundwater is dependent on the monsoon. But concentrated rainfall does not help infiltration. This is one of the reasons why more rivers are drying up and dying.” A delayed monsoon is also jeopardising the crop calendar. The life-cycle of crop in Bengal is delayed by 15 days, resulting in reduction of production, he adds.