Maldives wants a fund of last resort
Meanwhile, in the Maldives, President Mohamed Nasheed declared upon entering office that he would create a sovereign fund -- something of a last-resort insurance policy -- in the event that the country's 305,000 citizens would require relocation. The fund fell victim to budget shortfalls, but Maldivian officials have said it had the desired effect of raising awareness in the international community.
And while environmental migration is not a new phenomenon, the projected scale of human movement over a short period of time is unprecedented. But, noted University of New South Wales professor Jane McAdam, "there is at present no internationally agreed definition of what it means to be an environmental 'migrant,' 'refugee,' or 'displaced person,' and consequently, no agreed label for those affected."
Edward Cameron, former senior adviser to the government of the Maldives, added: "We see at the moment how many people are on the move in Pakistan." While the floods devastating that country have been displacing millions internally, Cameron asked, "What if they were on the move across an international border? They certainly wouldn't have refugee status."
But while questions abound over the status and rights of displaced persons, experts say that field of study is burgeoning compared to the study of sovereign rights of vulnerable countries.
McAdam, who has looked at the question of whether a disappeared nation could retain its U.N. seat, noted that there is no automatic triggering mechanism that "undoes" a state.
"Certainly states have ceased to exist in the past, but it's through occupation, war, state secession," McAdam said. The closest thing to an extinct nation would be a government in exile. Yet even that assumes the government will eventually return to its territory -- something climate change may make impossible.
"There's precedent for other things that we can draw on, but ... there's no self-executing formula for deciding when a country doesn't exist anymore," she said.
Cleo Paskal, associate fellow at Chatham House and author of "Global Warring: How Environmental, Economic and Political Crises Will Redraw the World Map," said one of her top worries is the fate of countries' maritime exclusive economic zones.
Those areas where countries have exclusive rights to the resources are measured from coastlines or offshore islands. But, Paskal noted, the laws assume the coastlines won't change or disappear. That's already happening.
Laws assume coastlines are a constant
"Any country with a coastline or offshore islands that are being used to anchor claims need to start thinking about if that coastline or offshore island is affected, and what will that do to the exclusive economic zone claims?" she said. "The core issue is that we have written our laws, regulations, subsidies on the assumption that the environment is a constant, and it isn't."
Moreover, as Paskal noted in a recent blog post, countries that take in climate "refugees" might make a case for governing the former nation's maritime zone -- something she described as a "very lucrative and geopolitically touchy proposition."
Meanwhile, Paskal and others warn that well before a country disappears under rising waters, it will face less provocative but deeply vexing problems.
"On your way down, before your country disappears, you've got desalination problems, agriculture problems, import problems. You might lose your fresh water; your land might start to degrade because of saltwater intrusion," Paskal said.