Feb 14, 2023, 3:29pm EST

These megacities are most at risk from rising sea levels, according to the UN secretary-general


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The News

Some of the world’s busiest and biggest cities, including New York, Cairo, Mumbai, Jakarta, Shanghai, Copenhagen, London, Bangkok, Buenos Aires, Lagos, and Los Angeles, are at risk of being flooded if global temperatures continue to creep up and cause further sea level rise, UN Secretary-General António Guterres warned Tuesday.

Guterres told the UN Security Council that “every fraction of a degree counts,” and that if temperatures rise by 2 degrees, it would lead to severe impacts on every continent.

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Guterres said rising sea levels are already leading to instability and conflict, and could further exacerbate global security. Shrinking landmasses could provoke “possible disputes related to territorial integrity and maritime spaces,” he added.

He added the danger is “especially acute” for nearly 900 million people, one-tenth of the earth’s population who live in coastal zones at low elevation, considering some coastlines had already seen “tripe the average rate of sea level rise.”

Rising sea levels would lead to an increase in climate refugees, as people are forced to move away from coasts.

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Numerous climate studies have backed up Guterres’ concerns that major cities could be at least partially underwater by 2050. The list of places at risk is by no means definite, though other large cities often named include Guangzhou, Miami, Osaka, and Amsterdam.

A 2022 report from the U.S. National Oceanic and Atmospheric Administration found that rising sea levels “will create a profound shift in coastal flooding over the next 30 years by causing tide and storm surge heights to increase and reach further inland.”