BANGALORE: Climate change is causing sea levels to rise in the country as well as changing coastlines, say experts.
“Land in and around Diamond Harbour, near the southern suburbs of Kolkata, is sinking and sea levels have risen by about 50 centimetres in the last 100 years,” said Prof Govindaswamy Bala of the Divecha Centre for Climate Change, Indian Institute of Science.
Speaking at a function at the Institute of Engineers on Thursday, he said studies indicate an ice-free Arctic Sea may be years, not decades away. The area of ice has declined by 49 per cent since 1979. The thermal expansion of the ocean leads to a rise in sea levels, Bala warned. “It could rise by a metre in this century. About 70 per cent of global coastlines will experience relative sea-level change. Coastal regions could see a rise of 60 cm in sea levels”, he said.
Bala said melting ice in the ocean does not contribute to sea-level rise but ice-capped mountains do. The entire ice sheet on Greenland is melting and Himalayan glaciers as well as glaciers like Andes are retreating, he noted.
He said carbon dioxide levels are relentlessly rising in the atmosphere. From 1958 to 2013, carbon dioxide levels have increased by 100 parts per million (ppm). “Last year, we crossed the 400 ppm mark, and this year we crossed it for about a week,” he added.
Bala said the Indian monsoon has a great amount of inter-annual variability. The IPCC report says rainfall may increase by 10 per cent and the monsoon duration by 10 days, he added.