Engulfed by water, is a state doomed to be wiped off the map?

"This is the greatest tragedy that a people, a country, a nation can face," former Maldives president Mohamed Nasheed told AFP.

According to UN climate experts (IPCC), sea level has already risen 15 to 25 cm since 1900 and the rise is accelerating, with an even faster pace in certain tropical areas.

Thus, if the rise in emissions continued, the oceans could gain almost an additional meter around the islands of the Pacific and the Indian Ocean by the end of the century.

This certainly remains below the highest point of the flattest small island states, but the rise in water levels will be accompanied by an increase in storms and wave-submersions: the water and the land will be contaminated by salt, making number of uninhabitable atolls long before they were covered by the sea.

According to a study cited by the IPCC, five states (Maldives, Tuvalu, Marshall Islands, Nauru and Kiribati) risk becoming uninhabitable by 2100, creating 600,000 stateless climate refugees.

- "Legal fiction" -

An unprecedented situation. States have of course been wiped off the map by wars. But "we have never seen a state completely lose its territory due to a physical event like the rise of the ocean", notes Sumudu Atapattu, of the University of Wisconsin-Madison.

However, the Montevideo Convention of 1933 on the rights and duties of States, a reference in the matter, is clear: a State is made up of a defined territory, a permanent population, a government and the capacity to interact with other states.

So if the territory is swallowed up, or no one can live on what's left of it, at least one of the criteria falls.

But "the concept of State is a legal fiction created for the needs of international law. So we could create a new fiction to include these deterritorialized States", pleads Sumudu Atapattu.

This is the idea behind the "Rising Nations" initiative launched in September by several Pacific governments: "To convince the members of the UN to recognize our nation, even if we are submerged by water, because it's our identity," Prime Minister of Tuvalu Kausea Natano told AFP.

Some are already thinking about how to use these Nation States 2.0. "You could have the territory somewhere, the population somewhere else, and the government in a third place," Kamal Amakrane, director of the Center for Climate Mobility at Columbia University, told AFP.

This would first require a "political declaration" from the UN, then a "treaty" between the threatened state and a "host state", ready to welcome the government in exile in a sort of permanent embassy and its population which would then have dual nationality.

The former UN official also draws attention to an ambiguity in the Montevideo Convention: "When we talk about territory, is it dry land or maritime territory?".

- "Ingenious humans" -

With 33 islands scattered over 3.5 million km2 in the Pacific, Kiribati, tiny in terms of land area, has one of the largest Exclusive Economic Zones (EEZs) in the world.

If this maritime sovereignty were preserved, then a State would not disappear, assure certain experts.

While some islets are already submerged and the shores are receding, freezing the EEZs would first of all preserve access to vital resources.

In an August 2021 statement, members of the Pacific Islands Forum, including Australia and New Zealand, incidentally "proclaimed" that their maritime zones would "continue to apply, without reduction, notwithstanding any physical change related rising sea level".

But, in any case, some simply do not consider leaving their threatened country.

"Humans are ingenious, they will find floating ways to continue living there," says Mohamed Nasheed, referring to floating cities.

But these states do not have the resources for such projects. The issue of financing the "losses and damages" caused by the impacts of global warming will also be a hot topic at COP27 in Egypt in November.

Even when defending "the right to stay" and not to abandon one's land and "his heritage", "you always need a plan B", insists Kamal Amakrane for his part.

With this in mind, he calls for the launch "as soon as possible" of a "political" process to preserve future uninhabitable states, "to give hope to the populations".

Because the current uncertainty "creates bitterness and disarray, and with that, we kill a nation, a people".