The rising temperature of Earth is causing water sources such as glaciers and lakes to rapidly retreat, according to, among others,, director of the Lawrence Berkeley National Laboratory and one of the leading scientific figures trying to get more research funding for alternative energy.
The effects of declining water supplies will be noticeable and harsh, according to Chu, who shared the Nobel Prize in Physics in 1997. Some effects can already be seen, he said.
"The Yellow River is now running dry in summertime," Chu said during a speech at the this week.
The Yellow River is fed by glacier and snowmelt from the Himalayas, which is declining. A huge portion of the world's population gets water from the Himalayas, so this is not a good sign for other areas as well.
In the United States, the snowpack in the Sierra Nevada mountains in California and Nevada is expected to decline by 30 percent to 70 percent by 2100, he said.
If it declines by 20 percent, people will be told to stop watering their lawns or flushing toilets often. A decline of about 50 percent or greater could rewrite the demographics of California. And a massive decline in the snowpack could cause a collapse of the agriculture industry, prompting a migration out of the state, Chu said.
Snow may actually increase in some mountain ranges and parts of the world. Many expect that dry regions will become drier, while . Warming, however, will prevent this extra rain and snow from getting stored in mountains, he said. Thus, a lot of it will run off before it can be used.
"(Water) is probably the first thing that will hit home," he said. "The water storage problem is becoming a mess."
Several start-ups andhave begun to increase their investments in systems that can for human consumption.
"The water issue is going to get much more prominence," predicted, chairman of the Cleantech Venture Network.