Global warming redistributed world's water resources

Rising temperatures worldwide are changing not only weather systems, but -- just as importantly -- the distribution of water around the globe, thereby affecting the availability of potable water, says a new study.

"This study shows how climate change is altering the spatial patterns and amounts of precipitation -- where it comes from and where it falls," said study co-author Myron Mitchell, professor at State University of New York College of Environmental Science and Forestry in the US.

"Such effects can drastically affect the availability of potable water and also contribute to the massive flooding we have seen in recent years," Mitchell noted.

The findings appeared in the journal Scientific Reports.

For the study, the researchers analysed more than 40 years of water samples archived at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, US.

The researchers found that over the years, there has been a dramatic increase, especially during the winter, of the amount of water that originated far to the north.

"In the later years, we saw more water derived from evaporation of the Arctic and the North Atlantic oceans," lead author Tamir Puntsag from State University of New York said.

Mitchell said the findings of the study will help scientists understand changes that are likely to affect global water resources.

With 85 percent of the world's population living in the driest half of the planet and 783 million people living without access to clean water, according to the UN, it is vital for scientists and policymakers to understand how a changing climate affects water resources.

"Our research helps our understanding of the sources of rain and snow and how these precipitation patterns have changed. Our study also sheds light on what is going to happen to water resources in the future," Mitchell said.