NASA visualises how sea levels will rise in Indian coastal regions

The Intergovernmental Panel on Climate Change (IPCC) in its “Climate Change 2021: The Physical Science Basis” report stated that the sea-level projections are based on data gathered by satellites and instruments on the ground, analyses and computer simulations. IPCC had flagged that sea levels around Asia in the North Indian Ocean have increased faster than the global average, with coastal area loss and shoreline retreat. NASA has used the same projections to make a visualisation tool that will help coastal regions prepare for sea-level rise and plan infrastructure accordingly. The report stated that :

• NASA’s Sea Level Change Team has created a sea-level projection tool that visualises future sea-level rise from the IPCC’s findings.

• Global mean sea level increased by 0.20m between 1901 and 2018.

• Relative to 1995-2014, the likely global mean sea level rise by 2100 will be 0.28-0.55m under a very low greenhouse gas emissions scenario and 0.98-1.88m under the very high scenario, IPCC has projected

• Sea level around Asia in the North Indian Ocean has increased faster than the global average, with coastal area loss and shoreline retreat. The regional mean sea level will continue to rise.

• By 2040, Mumbai’s sea level will rise by 0.12m compared to 0.4m in 2020; at Hiron Point in Sundarbans sea level will rise to 0.17m compared to 0.6m in 2020; Chennai will see a 0.10m rise compared to 0.3m in 2020; Cochin will likely see a sea-level rise of 0.15m compared to 0.6m; Bhavnagar 0.22m compared to 0.8m in 2020. These projections are based on an intermediate emission scenario where emissions have fallen globally but not to very low levels. The IPCC considers five socioeconomic Pathways (SSPs) which are essentially possible paths of growth human societies could follow over the next century.

• “What’s new here is a tool that we are providing to the community, to distribute the latest climate knowledge produced by the IPCC and NASA scientists in an accessible and user-friendly way while maintaining scientific integrity,” said Nadya Vinogradova Shiffer, programme scientist and manager at NASA.

• The tool can display possible future sea levels under several greenhouse-gas-emission and socioeconomic scenarios, including a low-emissions future, a “business as usual” trajectory with emissions on their current track, and an “accelerated emissions” scenario.