Climate change could make thousands of tropical islands “uninhabitable”

More than 1,000 low-lying tropical islands risk becoming “uninhabitable” by the middle of the century — or possibly sooner — because of rising sea levels, upending the populations of some island nations and endangering key U.S. military assets, according to startling new research published Wednesday.

The threats to the islands are twofold. In the long term, the rising seas threaten to inundate the islands entirely. More immediately, as seas rise, the islands will more frequently deal with large waves that crash farther onto the shore, contaminating their drinkable water supplies with ocean saltwater, according to the research.

The islands face climatechange-driven threats to their water supplies “in the very near future,” according to the study published in the journal Science Advances.

The study focused on a part of the Marshall Islands in the equatorial Pacific Ocean. Hilda Heine, president of the Marshall Islands, said in an interview that Wednesday’s journal article “brings home the seriousness” of the predicament facing her island nation.

“It’s a scary scenario for us,” she said.

The research also has ramifications for the U.S. military, whose massive Ronald Reagan Ballistic Missile Defense Test Site sits, in part, on the atoll island of Roi-Namur — a part of the Marshall Islands and the focus of the research.

The U.S. military supported the research in part to learn about the vulnerability of its tropical island installations. The Pentagon base at Roi-Namur and surrounding islands supports approximately 1,250 American civilians, contractors and military personnel.

The low-lying island, which rises barely 6 feet above the current sea level, is part of the vast Kwajalein coral atoll, a structure that formed as coral reefs grew around a sinking volcanic island long ago. That’s the origin of more than 1,000 other low-lying, ring-shaped atoll islands or atoll island chains across the Pacific and Indian oceans. Most are not populated. But some, such as the Marshall Islands or the Maldives, are the home of tens or even hundreds of thousands.

While seas are rising by 3.2 millimeters per year at the moment and are expected to rise faster in years ahead, Roi-Namur has a good chance of avoiding total inundation this century.

Pavel Rahman, Associated Press file Villagers in 2009 dig up some earth to help rebuild an embankment in Shatkhira, about 110 miles southwest of Bangladesh, after thousands of people were displaced from their homes by flooding caused by a deadly cyclone.