Small island nations see themselves in a vulnerable but still somehow hopeful situation, just like a sand castle.
The seas are rising from climate change and they are running out of room.
And with the US pulling out of the Paris global warming pact they also seem to be running low on time.
Scientists say some of the islands may not make it through the next 100 years. And they add that the US withdrawal makes that likelihood increase.
During Paris climate negotiations, small islands successfully campaigned for a stricter goal than the rest of the world wanted. But that goal is looking more unreachable.
Yet Marshall Islands President Hilda Heine says she has to be optimistic because she can't give up on her country and her culture.
