It's only half a joke. A recent report found that by 2030 demand for water will outstrip the world's supply by 40 percent. In the United States, the Colorado River and other major sources of water are drying up. The number of droughts worldwide is skyrocketing. Water is clearly no longer plentiful forever, even in wealthy nations.And Canada has a lot of water that other nations will someday soon not just want but badly need. Does this mean that wars over water are inevitable? No. But increasing scarcity of a resource necessary to life is how conflicts are born. So where does water fit into our current geopolitical tensions? What can we do now to avoid fights later? And ... can't we science out way out of this somehow?GUEST: Dr. Jay Famiglietti, hydrologist and  Global Futures Professor at Arizona State University; former Executive Director Emeritus of the Global Institute for Water Security at the University of Saskatchewan; host of the What About Water podcast