The driest January through June in New Mexico history came down to this: For the first time in scientist Craig Allen’s 25 years at Bandelier National Monument, Frijoles Creek past the monument’s Jemez Mountains visitor center went dry.
Oak and mountain mahogany trees barely leafed out.
Since Jan. 1, the Bandelier fire lookout has received less than half an inch of rain.
“You can evaporate that from a pan on a warm afternoon,” Allen said Friday.
Nearby, litter on the forest floor in the woods that ring the Valles Caldera at its driest had just 1 percent fuel moisture.
For comparison, the kiln-dried two-by-fours you buy at Home Depot measure 12 percent, said Bob Parmenter, chief scientist at the Valles Caldera National Preserve.
“They’re literally freeze-dried gasoline,” Parmenter said of the forests that grace the preserve. “Put a torch to them and they take off.”
That torch came June 26 in the Jemez Mountains south of the preserve when the Las Conchas Fire exploded in less than a week to become the largest forest fire in New Mexico history, taking more than 10,000 acres of the Valles Caldera and threatening Los Alamos National Laboratory and the communities around it.
The factors that set up trouble in the Southwest’s forests are complex – a warming climate and forest management practices over the 20th century that allowed a terrifying buildup of fuel. There was simply too much wood and plant material for the ecosystem to support, said Allen, an ecologist with the U.S. Geological Survey who has been studying the relationship between forest, fire and climate in the Jemez Mountains for 25 years. Something had to give.
That set the stage. Epic drought lit the match.
By any measure, current New Mexico drought conditions are extraordinary:
• Preliminary numbers suggest that, statewide, the six months since Jan. 1 were the driest such stretch in more than a century of record-keeping.
• Average spring relative humidity in Albuquerque – 21 percent – tied 1996 for the driest on record.
• The U.S. Bureau of Reclamation projects that runoff from mountain snow into Santa Rosa Lake on the Pecos River of eastern New Mexico is just 4 percent of average, the driest since the dam that created the lake was finished in 1976. The previous record dry year, 2006, was three times wetter.
• The Carlsbad airport went 223 days without rain before one one-hundredth of an inch fell June 2. It has not rained since.
• 80 percent of New Mexico is in “extreme drought,” according to the federal Drought Monitor.
Water managers around the state are feeling the shortfall. A number of communities, including Las Vegas, Portales and Tijeras, have imposed voluntary or mandatory water use restrictions because of dwindling supplies. And agricultural agencies that depend on surface water to supply farmers in the state’s river basins are struggling.
“It’s terrible out there,” said David Gensler, who oversees water supplies for farmers in the Middle Rio Grande Conservancy District.
The District, which provides water for Rio Grande valley farmers from Cochiti to Socorro County, has enough water in storage from previous years to provide a full allotment for farmers this year, but it is unclear what will be left for 2012 if we have another dry winter. “It could be a lot. It could be nothing,” Gensler said.
On the lower Rio Grande, the drought has left little water for farmers south of Elephant Butte Reservoir. And because of a new water-sharing agreement, most of what water is there must be sent downstream to farmers in Texas. Officials worked through the weekend trying to line up more water allocations, saying that if they didn’t, supplies will run out early this week.
Meanwhile, on the Pecos River, water in storage from previous years has kept farmers from going dry completely. But farmers around Carlsbad will get only half their normal allotment.
“It’s hot, it’s dry and there’s almost no moisture,” said Dudley Jones, manager of the Carlsbad Irrigation District.
A state on fire
Fire is by far the most visible consequence of New Mexico’s Year of Little Rain.
Since Jan. 1, nearly 1,450 square miles of the state has burned, the most in at least 15 years, according to Dan Ware, spokesman for New Mexico State Forestry.
Experts say two problems – long-term forest management practices and global warming – set the stage for this year’s explosion of fires.
“Forests within the southwestern United States appear particularly sensitive to drought and warmth,” a team led by Park Williams of the University of California Santa Barbara wrote last year in the Proceedings of the National Academy of Sciences. “Increases in wildfires and bark-beetle outbreaks in the most recent decade are likely related to extreme drought and high temperatures.”
“We know all over the world it’s getting warmer,” said Nate McDowell, a forest ecosystem expert with the Los Alamos National Laboratory. He spoke by phone from Santa Fe last week, because he had been evacuated from his Los Alamos home.
Past forest management practices have added to the risk. Fire suppression over the last century has left forests such as the woods around Los Alamos choked with timber and vulnerable to the sort of blaze that blew up June 26. When fires were allowed to burn naturally, frequent low-intensity fires would clear out undergrowth, leaving 40 to 60 large trees per acre, Parmenter said. Firefighting stopped most of those fires, and the woods in the Valles Caldera that burned had more like 1,500 to 2,000 trees per acre, according to Parmenter.
Allen has been watching the fuel build up for decades, and he and his colleagues knew the great drying that fuel went through in the first six months of 2011 – “the amount of powder in the powder keg” – posed enormous risks.
While those long-term factors set the stage, it was La Niña conditions in the Pacific Ocean, which push winter and spring storms to our north, that shoved us over the edge, experts said. “The immediate antecedent condition was good old La Niña,” Parmenter said.
Since January, the storm track that carries winter precipitation across North America has arched to the north, leaving Utah, Colorado and points north drenched, while New Mexico and Arizona have remained exceptionally dry.
Every day that went by without rain pushed the Jemez forest further into the danger zone. “You could feel this coming the last six weeks or so,” he said.
Firefighters saved Bandelier’s main ruins area and visitor center, along with Allen’s office, but more than half the park’s acreage burned.
When he returned last week, Allen noticed something remarkable: Water has returned to Frijoles Creek.
Upstream, the forest that once lined the creek is gone. “You don’t have all those trees sucking water out of the system,” Allen said.
— This article appeared on page A1 of the Albuquerque Journal