Don't imagine it will make any difference -- us developing countries are far more selfish than that, and frankly not one of us will consider their plight for more than a few seconds. Then it's off to the mall.
Sea level is only expected to rise about 30 cm in the next hundred years. Big deal, right?
Maybe. But the highest point in the Maldives is only 2.3 m. So clearly there's a decent slope on their beach and a small sea level rise might reach far inward.
How far? Let's model The Maldives (298 km2) as one circular island, whose center is 2.3 m high, so it looks like the top of an umbrella, minus its stem.
How much of the country will be lost with a rise of X cm in sea level? A simple bit of algebra and trigonometry gives:
(Click to enlarge.)
So if sea level rise is simply 20 cm, they will lose about 15% of their land mass. If it's, say, 60 cm, in this idealized model they would lose almost 50% of their land mass.
No wonder they're concerned. Too bad we won't help them.