RISING TEMPS AND DESERT WATER MANAGEMENT
posted by Michael Chihak
Drought and the desert go hand in hand, yet the most recent drought in Arizona had a characteristic unlike any other in the last 100 years: higher temperatures through the duration of the dry period, starting around 2000, a University of Arizona scientist says.
"I've researched all droughts (in Arizona) of the 20th century, and I found that in the most recent drought, the temperatures were warmer than average," geoscientist Connie Woodhouse said in an interview with Arizona Week. "That's a characteristic not existent in earlier droughts."
The consequences are important to consider, Woodhouse said. Warmer temperatures mean increased water demand and increased evaporation, she said.
That means water managers ought to pay closer attention, and they should know that because of ongoing climate change, temperatures likely will be warmer during future droughts, Woodhouse said. She added that she knows water managers are doing a good job including climate change information in their discussions and decisions.
Woodhouse has done extensive research on Southwestern climatology and is working on a tree-ring study that should bring greater understanding to the Sonoran Desert's monsoon seasons. Data from the study, to be available within the next month, could show a correlation between summer monsoons and winter rains in the Southwest.
"We can't predict the future, but if we use the past, we can see that we've had low flows (on the Colorado River) since 2000, the first year of the latest drought," Woodhouse said.
Is that drought over now that the U.S. Bureau of Reclamation says Upper Colorado Basin snow pack was way above normal this past winter? "It depends on who you talk to," Woodhouse said.
Arizona water managers have said the big snow pack and resultant federal decision to increase the amount of water moving down the Colorado River and into Lakes Powell and Mead means there won't be a shortage at current usage levels until at least 2016.
Whether the drought has ended or not, Woodhouse had this advice for water managers in the state: "I would suggest they consider permanent ways to conserve water."
