llink: http://news.nationalgeographic.com/news/2014/05/140516-drought-wildfire-insects-southwest-connect-dots/
The Stevens Creek Reservoir in Cupertino, California, was almost dry in March 2014.
PHOTOGRAPH BY MARCIO JOSE SANCHEZ, ASSOCAITED PRESS
PUBLISHED MAY 16, 2014
The wildfire season arrived early this week in southern California, at a time of the year when skies usually are covered in cooling clouds of gray.
But this spring, the skies have been more like ashen gray, and fire agencies have responded to nearly 1,400 fires this year—twice the typical number, a Cal Fire spokesperson told the Los Angeles Times. A New York Times report May 16 said fire season in the West is now 75 days longer each year than it was a decade ago.
At the root of the problem is the deep, three-year drought that continues to plague California, and warmer winter weather that shrinks the snowpack in the Cascade and Sierra Mountains—a recipe that increases likelihood of wildfires. Studies indicate that the number and size of Western fires is up, and scientists say this drought may be the start of a long-term trend, noting that other Western droughts during the past 1,000 years have been more severe and could repeat.
Firefighters drive through a burned-out area in the hills around San Marcos, California, on May 15, 2014.
PHOTOGRAPH BY MIKE BLAKE, REUTERS
California's water supplies are short, many rivers are low, and forests are dry. Operators of the state's network of of dams, reservoirs, and canals have cut back water deliveries to 5 percent of normal. Cities and farmers rely on this state water to supplement local supplies. California, with the nation's largest agricultural economy, relies heavily on irrigation water for crops. The California Farm Water Coalition estimates that nearly 800,000 acres of farmland will be left fallow this year because of the lack of water. Farmers in the Sacramento and San Joaquin valleys are digging wells to keep some land in production, but this is depleting aquifers.
An Exceptional Drought
Drought Monitor, which updates national drought trends each week, reported on Thursday that half the area of the lower 48 United States is in drought, and it classified all of California as being in "severe to exceptional" drought. The state hasn't been this dry in 14 years, according to USA Today.
Other states are short on water, too. Parts of Nevada and southern Oregon are in drought after a winter that was light on snow. Luckily the northern Rockies and Cascades received several late-season snowstorms, but snowmelt from those mountains flows into the Columbia and Missouri River systems. That will help hydropower and irrigation in the Northwest and northern Rockies but is of no value to those in California and the Southwest.
New Mexico and Texas are especially dry. Texas's state climatologist told a gathering in San Antonio this week that the state's four-year drought is among the five worst in 500 years.
The Panhandle region of Oklahoma and Texas is seeing a return of massive dust storms, making some ask whether we are seeing a"New Dust Bowl," a reference to the devastating period for farmers during the 1930s. Boise City, Oklahoma, resident Millard Fowler told National Geographic, "When people ask me if we'll have a Dust Bowl again, I tell them we're having one now."
A water bomber makes a drop on flames as the Cocos Fire continues in San Marcos, California, on May 15, 2014.
PHOTOGRAPH BY MIKE BLAKE, REUTERS
Heat, Dryness, and Bugs
A five-decade study by Oregon State University climate scientist Philip Mote indicates that Western mountain snowpacks are shrinking. If this trend toward less snow keeps up, the shortfall will impact a region that relies heavily on stored reservoir water from snowpack to keep fish in rivers, fields green, and cities watered year-round.
Last week, the new National Climate Assessment from the U.S. government examined the prospects for the West. For the Southwest,it said: "Increased heat, drought, and insect outbreaks, all linked to climate change, have increased wildfires. Declining water supplies, reduced agricultural yields, health impacts in cities due to heat, and flooding and erosion in coastal areas are additional concerns."
Relief Coming This Fall?
But there may be hope on the horizon. Every few years a Pacific Ocean disturbance called El Niño comes along: Warm ocean water moves east, and the west coast regions of North and South America get a lot of rain. NASA satellites show El Niño conditions developing in the equatorial Pacific Ocean.
If an El Niño arrives, California and the American West may get some much-needed relief from years of drought. But El Niño also could bring too much water too quickly, if its storms are extreme. That's what happened during the last major El Niño, in 1997-98. Between drought and deluge, nature's middle ground can be elusive.
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