Global Warming Expert Fears 'Refugee Crisis'

April 2, 2007 — -- Within two or three decades, there could be one and a half billion people without enough water, according to a new report on the impacts of global warming.

Such droughts would produce "refugee crises like we've never seen," as one of the study's lead authors told ABC News.

Scientists working on the "Impacts, Adaptation and Vulnerability" report have been telling ABC News for months that its findings, once public, would be alarming. The report is being prepared by the IPCC, the Intergovernmental Panel on Climate Change, made up of 2,500 experts in the field.

Scientists are hammering out that report's final wording in Brussels and are due to announce it on Friday.

But its basic findings, they say, won't change.

Drafts of the IPCC report depict a world already changed dramatically in the past 35 years by manmade global warming, with increasing drought, heavy precipitation and flooding.

It also says humankind is in for much worse in the next few decades.

The IPCC scientists are finalizing one chart that projects how, with each degree of future warming, Earth's natural life-support systems break down more and more.

It predicts mountain glaciers and snow-pack melting away around the world, faster than scientists thought possible only 20 years ago.

Ancient civilizations that have depended for millenia on fresh water from melted ice and snow are facing unprecedented crises, according to the two reports so far released.

For example, Himalayan glaciers and snow-pack which feed the Ganges and Brahmaputra rivers and which support hundreds of millions of people, are fast disappearing in the rising heat.

"What you can end up with is people homeless in places like Bangladesh having to move to places like India and China -- which will not be particularly welcoming to refugees," Peter Schwartz, a future systems analyst, told ABC News.

"You will have a refugee crisis like we've never seen," he said.