Some resource experts such as Thomas Homer-Dixon, a University of Toronto researcher, warn that increasing competition for water could be the leading cause of regional warfare in the coming century. Iraq, Syria and Turkey have in recent years exchanged verbal threats over their use of shared rivers. And if predictions of climate change prove true, more erratic weather will bring more frequent droughts, with changing weather patterns bringing more rain to some portions of the world while possibly turning others into deserts. But manmade climate change is still a theory embraced by many scientists and advocates while disputed by others. There's no such controversy over water use.
Shortages are already a fact in many areas.
What We Can Do About It. It's already in widespread use in the oil nations of the Middle East. But for other parts of the world that are just as arid but less affluent, it's out of the question for the foreseeable future. Lake Allatoona, a reservoir outside Atlanta, is among those the EPA identifies as threatened Water conservation techniques can help. Drip irrigation systems are using far less water to grow crops from the Middle East to the Southwestern United States.