Swansea experts to fix Amazon rainforest satellite problem
19 February 2014 Last updated at 20:28 GMT
It is a mystery that has baffled scientists for more than a decade - why does the Amazon rainforest seem to grow greener during droughts?
The answer lies in how the forest is photographed from Space.
Nasa realised that its satellites were producing an optical illusion and it called in experts from Swansea University to fix the problem.
As Carwyn Jones reports, the real picture casts a very different light on climate change.