Having your homeland engulfed by the ocean because of climate change doesn’t make you a refugee, or so the High Court of New Zealand ruled last week when it dismissed the case of Ioane Teitiota, a man from the low-lying Pacific island nation of Kiribati. Refugee status is based in the need for “protection … from political or other forms of persecution,” and Teitiota sought to bend the definition by claiming he was “persecuted passively” by climate change. Had this argument prevailed, his case might have carried huge implications for the millions of people who could be displaced by rising sea levels in the coming decades. As the presiding judge wrote: “At a stroke, millions of people who are facing medium-term economic deprivation, or the immediate consequences of natural disasters or warfare, or indeed presumptive hardships caused by climate change, would be entitled to protection under the Refugee Convention.... It is not for the High Court of New Zealand to alter the scope of the Refugee Convention in that regard.”

Experts on the plight of the Pacific islands agree that it doesn't make sense to reinterpret the Refugee Convention (and that relaxing its rules to cover climate change could actually weaken the protection it offers victims of persecution). The problem is, international law is wholly lacking in norms that cover people whose homelands become uninhabitable—or simply disappear. “There’s a real gap,” said Walter Kälin, a prominent Swiss humanitarian and lawyer, and a member of the United Nations Human Rights Committee. “These people are not protected.” Even if the islanders aren’t refugees, they are in trouble: Teitiota's home of Kiribati, which has a population of about 100,000, may have to be abandoned by 2030 if the ocean contaminates its scant sources of fresh water, and the low-altitude nations of Tuvalu, Tokelau, the Maldives, and the Marshall Islands, which have a combined population of just under 500,000, may not be far behind.

If the I-Kiribati (the term for Kiribati nationals) and other Pacific islanders are not refugees, the question remains, what are they—and what conventions can be put in place to protect them? Kälin is hoping to address this with a new project called The Nansen Initiative, launched last year to devise strategies “for people displaced across borders due to natural disasters and the adverse effects of climate change,” of which the islanders are the most extreme example. There will be a few stumbling blocks. For one, the nations that would be signing on to accept these migrants are anxious about the influx. “The issue is not so much the Pacific Islands, which number altogether less than two million people, but if the precedent is set and then you’ve got sea level rise in Bangladesh, you could have tens of millions of people,” said Beth Ferris of the Brookings Institute. Most averse to the discussion are the islanders themselves, whose homeland is inextricable from their culture and way of life. “On the surface, the Nansen Initiative may not seem controversial, but that might be a simplistic view at this early stage,” warned the prime minister of the Cook Islands at a Nansen consultation in the Pacific in May.

Many nations have focused instead on shaming the western industrial giants whose greenhouse gas emissions are, literally, drowning them; the Maldives famously held a cabinet meeting under water in 2009. But it’s too late to keep these islands above sea level—studies show the impacts of carbon dioxide are essentially locked in for the next 1,000 years—and when the time to move does come, many hope a migration en masse could be less traumatic than broad dispersal; as Jeffrey Goldberg noted recently in an immersive piece about Kiribati for Bloomberg Businessweek, life on the islands is structured around traditional families and clans that this cataclysm could shatter. In the hopes of preserving their statehood, and their culture, the Maldives have approached Australia about buying land on which to rebuild, and the president of Kiribati has purchased a 6,000-acre tract on the mountainous islands of Fiji. Both countries have also looked into the more futuristic option of building artificial islands that would float on the waves. In the Maldives, the scheme would double as a ritzy golf course; in impoverished Kiribati, it’s harder to imagine who would foot the bill.

If their quests for a new homeland fail, the people of the Pacific will find themselves adrift in international waters, and this is where the lack of legal protection comes in. Though there exist a handful of conventions to protect people who have become stateless, Kälin doubts they would do much good: They are not widely ratified, and in any event do not provide the stateless person with the right to be admitted to other countries. What’s more, Kälin said, the island governments would likely hang on in exile as long as possible, even if, as the office of the United Nations High Commissioner for Refugees has noted, they “would largely lack capacity to enforce ... laws” and “would struggle to guarantee even basic rights or services to ... citizens.”