A New Zealand scientist says some Pacific islands are expected to struggle with the effects of climate change, by the middle of this century.
Penehuro Fatu Lefale from the Met Service led the study into small islands for the Intergovernmental Panel on Climate Change.
He says water shortages are expected to increase to the point where demand can't be met during low rainfall.
And Mr Lefale says that will impact on food security, fisheries, human health and tourism.
Mr Lefale says different parts of the Pacific are likely to experience different problems, but he believes the entire region will be hard hit.