Mumbai among cities facing biggest threat due to rising sea levels: WMO Report

With global oceans warming faster than ever before, countries like India, with their vast coastal populations, are particularly vulnerable.

According to a World Meteorological Organization report, Mumbai will be among the cities most affected as sea levels rise around the world (WMO).

The report shows that even if global warming is limited to the Paris Climate Agreement's goal of 1.5 degrees Celsius, there will still be a significant rise in sea level.

In their report, the organisation expresses reservations that the likelihood of breach [temporary] of the 1.5°C limit of the Paris Agreement is only increasing with time as global temperature for eight consecutive year reached 1°C above pre-industrial levels.

"The average global temperature in 2022 was about 1.15 [1.02 to 1.27] °C above the pre-industrial (1850-1900) levels. 2022 is the 8th consecutive year (2015-2022) that annual global temperatures have reached at least 1°C above pre-industrial levels, according to all datasets compiled by WMO. The likelihood of – temporarily – breaching the 1.5°C limit of the Paris Agreement is increasing with time," they said in their report.

The report stated that even if the global heating was limited to 1.5 degrees, the sea levels will still rise and countries like India, Bangladesh, China and the Netherlands are all at risk.

The rising sea levels bear negative consequences for the coastal ecosystems, it worsens the intensity of storm surges, flooding and can lead to the contamination of soil and groundwater with salt impacting food security.

The WMO said that, apart from Mumbai, Shanghai, Dhaka, Bangkok, Jakarta, Maputo, New York, Buenos Aires, Santiago, lagos, Cairo, London, are among the most threatened cities by the sea level rise.
The WMO suggests that rise in the global mean sea levels was facilitated by loss of ice on land, melting of glaciers and ice sheets and thermal expansion from ocean warming.

The report also suggests rise in sea levels by two-three meters over the next 2000 years if the temperature rise is limited to 1.5 degrees. Higher temperatures will lead to more rise in sea levels which could prove catastrophic.

WMO says a 2°C warming could cause a rise of 2-6 m, while 5°C would mean 19-22 m rise in sea levels. This is alarming as the United Nations has said that world could see a 2.4-2.6°C rise in temperatures.

India at risk

The report highlighted India's vulnerabilities, such as water insecurity caused by salinity and a decline in fish production.

India has a 7,500-kilometer-long coastline divided into nine coastal states, 12 major and 200 minor ports, and could face serious long-term consequences.

Anjal Prakash, research director at the Bharti Institute of Public Policy and lead author for IPCC reports, emphasised the need for more adaptation measures to protect fishermen's livelihoods and ensure water security in terms of providing safe and clean water to coastal residents, adding that there needs to be more discussion at the policy level not only for adaptation, but also to map climate impacts at the local level.

Thermal expansion responsible for rising sea levels

According to the WMO report, thermal expansion is responsible for 50% of sea-level rise between 1971 and 2018, with glacier ice loss accounting for 22%, ice sheets accounting for 20%, and changes in land-water storage accounting for 8%.

Due to the potential intrusion of sea water beneath the Antarctic glaciers, there is a risk of much higher sea-level rise. The report emphasises the need for more policy discussion to map climate impacts at the local level and to take more adaptation measures to protect coastal populations' livelihoods.

Read the full report here