Or, the UN, the missing environmental refugees, the missing map and the moving goalposts.
There is good overall coverage here.
The UN environmental program (UNEP) had a webpage claiming that there would be 50 million environmental refugees by 2010, along with a nice map of where they might likely come from.
When they started to take fire from this clearly incorrect prediction (It was made in 2005), they just said, "no we didn't say that and took the page down!"
And now? Apparently the 50 million refugees will show up in 2020. They just missed the first bus, I guess: