Building resilience against the megadrought

A good eye-opening book by William deBuys - - A Great Aridness: Climate Change and the Future of the American Southwest (2011).  The book paints a picture that is not pretty - - ". . . what the Southwest might look like when the heat turns up and the water runs out."  The U.S. Southwest is an important economic, cultural, and technological center.  It will be under an intense microscope as climate change takes hold.  The Southwest, vulnerable to water shortages, rising temperatures, wildfires, a host of other environmental change in the United States, will draw an international audience.

Consider the following point the book makes and the role engineers will play:

Unfortunately, there's a possibility that the next megadrought has already begun - - we just don't know it yet.  The character of a drought becomes clear only retrospectively, and every long drought includes wet years that break the pattern of sustained dryness.  A megadrought, by definition manifests only over a span of decades.  In a way, our decisions for the future should be the same, no matter whether we are a few years inside a megadrought or lucky enough to have decades of relative abundance ahead of us.  Deep, crushing cycles of drought are part of the natural history of the Southwest and, for all practical purposes, they always have been.  Building resilience against drought into the region's water systems and cultural practices would be a wise course, irrespective of the cause or timing of the next emergency.  Perhaps the dangers now arising from anthropogenic climate change will goad us into doing the things we should have been doing all along.  This is especially urgent because the next megadrought will pose unique challenges.  "You can probably bet your house," says Overpeck {Jonathan Overpeck, professor of geosciences at the University of Arizona, where he also codirects the Institute of the Environment}, "that unless we do something substantial about these greenhouse gas emissions, the megadroughts of the future are going to be a lot hotter than the ones of the past.  So their impacts are going to be a lot more dramatic."