While it’s impossible to know precisely what will happen in the future – and it’s worth pointing out that some research suggests a few island states might not be doomed by rising sea levels – many scientists fear that, no matter what mitigations we make, we’ve already condemned some countries to a physical disappearance. Even if we switched off all emissions now, we probably already have enough climate change-causing greenhouse gas emissions to result in another foot or two of sea level rise in the coming years. “It might be that no amount of technology will allow us to prevent inundation of some low-lying island nations,” says Michael Mann, a renowned meteorologist at Pennsylvania State University. “That’s a reminder of what I like to call the procrastination penalty, of certain tipping points that we’ve physically and societally crossed.”

If we somehow managed to cap our man-made temperature rise at just 1.5C above pre-industrial levels – as island nations have called for – most of them could remain above water. But most other nations, especially more developed ones, seem more comfortable considering a global temperature rise 2C or even 3C above pre-industrial levels. “The Pacific island states have been leading the pack in terms of alerting the planet Earth to the fact that these small islands, which produce almost zero greenhouse gas emissions, are sitting on the frontlines of climate change,” says Jose Riera, a special advisor at the UN.

At this point, however, that scenario seems nearly unavoidable, forcing the question of what will transpire when the losses begin to unfold. While nations have been absorbed by other nations or split off to form new ones in the past, never before has a country literally disappeared.