All at sea

The impact of warming oceans is a neglected threat

The World Meteorological Organization (WMO), an agency of the United Nations, has sounded its annual warning that appears to go largely unnoticed in the excitement over investment in electric vehicles, solar power, and green hydrogen as key mitigation strategies in India’s fight against global warming. In a report published this week, the WMO said sea levels rose by 4.5 millimetres (mm) a year on average between 2013 and 2022 — which is more than three times the rate at which they rose between 1901 and 1971. The WMO was not, in fact, making a new point; it flagged the risk of rising sea levels almost each year. This year, the report has highlighted the fact that Mumbai, India’s financial capital, which has expanded significantly on reclaimed land, is among the cities facing the biggest threat from rising sea levels. This area is also the locus of some of India’s largest ports. The rise in sea level is the result of acceleration in the loss of ice from the Arctic and Antarctic regions as a result of global warming. The Indian Ocean is among the “hotspots” in this respect.

The impact of rising sea levels ranges from long-term problems such as subsidence, water and soil salinity, and diminishing livelihoods. Coastal agricultural communities will suffer falling productivity from declining soil quality; fishing communities around the world are already facing depleting stocks as warming oceans impact the production of natural feedstock for fish. These are long-term problems that manifest themselves over time. But the immediate impact can be seen in the intensification of storm surges when tropical cyclones occur, when rising sea levels cause an exponential increase in the height and velocity of sea waves. For example, Cyclone Amphan, which hit India’s east coast in 2020, brought seawater 25 km inland and flooded the Sunderban delta, which is, globally, among the regions most vulnerable to rising sea levels.

Limiting the rise in sea levels depends on a global approach to mitigation strategies in terms of containing emission and reforestation to limit global warming to 1.5 degrees Celsius above pre-industrial levels. As the contentious discussions at each year’s climate-change talks demonstrate, progress here is patchy and contingent on reluctant developed countries’ willingness to underwrite the costs developing nations will incur to cope with the crisis that they (developed countries) have largely been responsible for. But where India’s mitigation strategies fill the policy space, largely from a vocal private-sector lobby that has benefited from them, the no less critical issue of adaptation is missing in the public discourse. For instance, reorienting fisherfolk to alternative livelihoods and creating infrastructure for drinking water along the worst-hit areas are solutions that can profitably begin well before the crisis grows out of control. Urban flooding and water management are areas that demand much more attention than they get. Neighbouring, low-lying Bangladesh is an example of a country where an economic miracle is threatened by rising sea levels; it is among the countries that record the highest number of “climate refugees” who have lost homes and livelihoods to warming oceans. This is the last predicament India should face as it seeks faster economic growth.