We're now in the seventh year of drought in much of North America, and there are few signs that the situation will be changing any time soon. Across the American West, the snow pack -- the source of water through the summer months -- was only 40-75% of normal. Of course, "normal" may have been a historical aberration...
While the current drought run isn't yet as bad as the "Dust Bowl" of the 1930s, despite our increased demand for water in agriculture and urban centers, the persistence of this condition is making a lot of people wonder what it would take to push us into another disaster. Fortunately, there's some really interesting work being done now in figuring out the climate mechanisms behind persistent droughts. Jennifer at WorldTurning points us to Why So Dry?, a non-specialist-friendly write-up produced by NASA's science news service describing how droughts work, how they connect with larger climate patterns (particularly El Niño/La Niña effects), and what more we need to learn.
One of the links from the NASA writeup is to the National Drought Mitigation Center's weekly Drought Monitor; the image at the top of this page is of the most recent map. The monitor page gives detailed analysis of current conditions and forecasts of upcoming changes, and provides animated maps of the last six weeks, twelve weeks, and year's drought.
As important as it is to understand drought as a geophysical condition, it's also a human event. If we can't change the weather, what can we do to mitigate drought effects? The Rocky Mountain Institute's "soft path" concept is one approach -- decentralize water systems, use green infrastructural systems to reclaim and reuse run-off and gray water, manage water demand more effectively, and distribute the best, most water-efficient technologies available as widely as possible -- but this may also be a time when the developed world can take a hint from the developing, and start looking at some unconventional approaches to using and acquiring water.