Here's What Happens if Your Island Nation Goes Underwater

Dec 10, 2015

Sea level rise and increasingly extreme weather are among the most visible impacts of climate change. Coastal communities around the Cape and Islands are facing skyrocketing insurance rates, and damage to homes and infrastructure. But for the residents of small island nations, climate change poses an existential threat. 

The Republic of Kiribati (pronounced Kiribas) is made up of 33 small islands in the Pacific Ocean, about halfway between Australia and Hawaii. They're atoll islands -- slim strips of sandy land sitting atop coral -- and most of their land is no more than six or seven feet about sea level. 

Whether or not they are completely submerged in ocean water depends on emissions over the next century. It's possible that the earth could see six feet of sea level rise in the coming centuries. The good news is that's unlikely to happen by 2100.

The bad news is, atoll islands like those in Kiribati could be uninhabitable long before the islands are fully submerged, recent research suggests.

That's because repeated ocean flooding will contaminate farming land and drinking water. Geologist and oceanographer Curt Storlazzi of the U.S. Geological Survey says that the islands have a very limited freshwater "lens." 

"If you have a wave-driven flooding event that puts oceanic salt water on top of the island and contaminates the water...one part per thousand salt in the water [means] humans can't drink it," he says.

If an island nation does go completely underwater, it has a pretty big legal problem. 

Experts say there are four criteria for statehood: land, a permanent population, a government, and international recognition. Without all four, a country would technically lose its standing under international law. 

Michael Gerrard, director of the Sabin Center for Climate Change Law at Columbia University, says even a small population of a few dozen could maintain a nation’s status. Still, he says legal scholars are considering a workaround for the possibility that island nations do eventually become abandoned or submerged. 

"There is now talk of a new species called an 'ex-situ state,' a state that would exist outside the territory where it had previously existed," he said. "But that has never happened and it would require a new species of international law."

Gerrard says this hasn’t reached diplomatic circles yet, and island nations have more pressing concerns. But Kiribati president Anote Tong says he thinks it should be on the international community’s agenda.

Another issue for island nations is what happens to their exclusive fishing rights in their territorial waters if their land goes away. A group of atoll nations announced a new alliance yesterday that they say covers 10 percent of the ocean and 50 percent of tuna fishing. Fishing is clearly an important source of revenue for these nations.

Gerrard says that technically, if you don’t have a coastline, you don’t have an "exclusive economic zone," that is, the area where only that nation's fishermen can fish.

But international law does include some provision for locking in a nation's coastline despite rising waters. Gerrard says some nations have taken steps to conduct formal surveys and try to secure their exclusive economic zones against the rising tide.