CHENNAI: As many as 10 lakh lives and 144 sq km of land in Chennai would be in danger if the sea level rises by a metre by 2050, according to a study, which pegs the loss due to such a development at `7,01,790 crore. The West Antartic Ice Sheet (WAIS), which lies mainly on bedrock under the sea, is showing signs of decreasing mass. Glaciologists believe it holds enough water to raise sea levels by 4.8 m. The Totten glacier, East Antartica, which is melting rapidly, holds enough water to raise sea levels by 3.4 m.
The study, being done by the Tamil Nadu State Land Use Research Board, is part of the Tamil Nadu State Action Plan on Climate Change. It takes into account global warming and greenhouse emissions, and stresses that coastal cities in the State, like Chennai, should be prepared for a one metre rise of sea levels by 2050.
According to the State Action Plan on Climate Change, there is a high chance of an increase in frequency and intensity of climate-related natural disasters. It links sea-level rise to coastal erosion, storm surges, coastal flooding and salt-water intrusion.
The study takes into account storm surges, tides and higher mean sea levels, and predicts that future storm surges, which are likely to be more frequent and more intense due to climate change, would reach between 4.35 m and 6.85 m, affecting up to 1,963 sq km. Also taking into account the Gross State Domestic Product for TN in 2016 (`12.12 lakh crore), it says the rise in sea level would result in 50-55 per cent loss of GSDP.
Among the key points mentioned in the report is that 2.46 lakh households, with a population of nearly 10 lakh, would be at risk due to the rise in sea level. In Kancheepuram and Thiruvallur, more than 5 lakh people are expected to be at risk.