Image courtesy of Nature Geoscience.Droughts aren’t just a natural phenomenon. Humans’ land and water use patterns affect how dry spells play out, according to an article by an international group of experts released Feb. 2, 2016, in Nature Geoscience.
“This is important because how we understand the problem drives what we do about it,” said Mark Svoboda, co-founder and one of the original U.S. Drought Monitor authors and leader of the Monitoring program area at the National Drought Mitigation Center, based at the University of Nebraska. Svoboda is a co-author of the article in Nature Geoscience. “We produce drought monitoring maps, but that’s the easy part. The harder question is, now that you know how dry it is, what are you going to do about it?”
Remember the hydrologic cycle? Water comes down as rain or snow, and goes up as evaporation (or, to be technical, evapotranspiration, which includes water vapor that plants exhale). That hasn’t changed, but the newly published article explicitly acknowledges that climate is no longer the only driver of the cycle. Irrigating crops (including lawns), land use/land cover change (urban sprawl), storing water behind dams or piping it hundreds of miles are just some of the ways that human activities speed up, slow down or alter the course of water’s flow.
The article calls for research into how natural events, such as lack of rain, affect human systems, and how human systems affect natural events. This type of research is challenging because traditional academic and professional disciplines tend to focus either on physical systems or on social systems, but not on both. The team of scientists from Europe, North America and Australia also suggests that the definition of drought be broadened to include human-induced drought and human-modified drought.
Although drought monitoring maps are some of its best-known products, the National Drought Mitigation Center was established in 1995 to help convey the idea that people can and should take action ahead of time to reduce their exposure to drought. The center has collaborated and consulted with scientists and policy makers around the world and across the U.S. to implement drought monitoring and reduce vulnerability to drought.
Find the full article at Nature Geoscience: http://www.nature.com/ngeo/journal/v9/n2/pdf/ngeo2646.pdf
-- Kelly Helm Smith