Mangalore faces high risk of sinking if sea levels rise, says Nasa study

NEW DELHI: Man galore in Karnataka is at a higher risk of flooding from rising sea levels because of melting glaciers than coastal cities such as Mumbai and New York, Nasa data shows.

Over the next 100 years, glacial melt could push up Mangalore sea levels by 15.98 cm compared to 15.26 cm for Mumbai and 10.65 cm for New York, says the study in the Science Advances journal. Mumbai and New York were believed to be more vulnerable.

The findings are based on a forecasting tool, gradient fingerprint mapping( G FM ), developed by the scientists at N as a’ s Jet Propulsion Laboratory.

It allows planners to see exactly how melting glacier scan push up sea levels for 293 major port cities, including three from India — Mangalore, Mumbai in Maharashtra and Kakinada in Andhra Pradesh.

“As cities and countries attempt to build plans to mitigate flooding, they have to think about 100 years in the future and they want to assess risk in the same way that insurance companies do,” said Erik Ivins, senior scientist at the laboratory.

GFM will show how sensitive local sea-level rise is to glacial melt, allowing scientists and planners to identify the ice sheets that pose bigger risk. A nice sheet is a continental glacier that covers a large area.

Almost 75% of the world’s freshwater is stored in glaciers and ice sheets and their melting, because of global warming, is a major contributor to rising seas.

The rise is not uniform across the globe because of gravity, the “push-pull influence” of ice, the wobble of the planet and local factors.

Shrinking ice sheets exercise lower gravitational pull on sea waters, allowing them to flow away. Diminishing ice mass allows the land below to swell, and this change in surface impact thewobble– orrotation-- ofearth, allof which influence howwater is distributed across the planet.

Rising seas erode coasts and can fuel storm surges and flooding.

Under the high emissions scenario for greenhouse gases, sea level will rise by 0.51-1.31m by 2100, according to National Oceanic and Atmospheric Administration.

The Indian subcontinent is likely to lose 14,000 sq km of land if sea level rises by a metre, according to some estimates.

In India, almost 40 million people will beat risk from sea-level rise by 2050, according to a UN report, with people in Mumbai and Kolkata at higher risk.

Vulnerability is not just calculated by sea-level rise but also the life and property at risk, which puts densely populated cities such as Mumbai andKolka ta at a higher risk than smaller coastal towns and villages.

The other major cause of sealevel rise is the thermal expansion of ocean waters. Water expand son heating and there has been a marked rise in average global temperatures of oceans since pre-industrial times.

The N as a study was published on the pen ultimate day of the climate- change talks in Bonn, where 20 countries committed to weaning themselves off coal that producesabout40% oftheworld’s electricity—a major contributor