How the California Drought Is Increasing the Potential for Devastating Wildfires

3 minute read

California’s four-year drought has already cost the state billions of dollars and placed thousands of jobs at risk. Now scientists say it has the potential to strengthen wildfires that could destroy homes, affect watersheds and cost hundreds of millions of dollars to extinguish during the warm summer months.

“We are seeing wildfires in the United States grow to sizes that were unimaginable just 20 or 30 years ago,” U.S. Forest Service Chief Tom Tidwell told lawmakers this week. “We expect 2015 to continue the trend of above average fire activity.”

In part because of the increased risk caused by drought, the Forest Service anticipates spending as much as $1.7 billion and mobilizing more than 10,000 people to fight wildfires this year. More than 120 wildfires have occurred on National Forest land in California already this year, according to a Forest Service spokesperson.

Climate change, at least in part, lies at the heart of growth in both the frequency and severity of wildfires in recent decades. Higher temperatures have left forests throughout California dry and flammable, according to Wally Covington, a forest ecology professor at Northern Arizona University. Tree death, another product of the drought, has also increased the chance of wildfire. More than 12 million trees in California forests have died and more are expected to do so soon, according to a Forest Service report.

See How California Is Using Its Diminishing Water Resources

The Los Angeles Aqueduct Cascades are seen in Sylmar
The Los Angeles Aqueduct Cascades, which bring water 223 miles from the Owens River in the eastern Sierra Nevada mountains, and 137 miles from the Haiwee Reservoir, are a major source of water for Los Angeles. Seen here in Sylmar, Calif. on May 4, 2015. Lucy Nicholson—Reuters
The Los Angeles Aqueduct Cascades are seen in Sylmar
The Los Angeles Aqueduct Cascades are seen in Sylmar, Calif. on May 4, 2015. California's snowpack, which generally provides about a third of the state's water, is at its lowest level on record. Lucy Nicholson—Reuters
A creek is seen in Northridge
With the country's most populous state entering the fourth year of a devastating drought, Governor Jerry Brown has ordered an overall 25 percent cut in urban water use though the first statewide mandatory reductions in California's history. The suppliers with the highest per capita water use would have to accept a 36 percent cut. Lucy Nicholson—Reuters
A tractor ploughs a field next to a canal in Los Banos
A tractor ploughs a field next to a canal in Los Banos, Calif. on May 5, 2015. California water regulators on Tuesday adopted the state's first rules for mandatory cutbacks in urban water use as the region's catastrophic drought enters its fourth year. However, the state's massive agricultural sector, which the Public Policy Institute of California says uses 80 percent of human-related consumption, has been exempted from cutbacks.Lucy Nicholson—Reuters
A worker walks through farm fields in Los Banos
A worker walks through farm fields in Los Banos, Calif. on May 5, 2015. Urban users will be hardest hit, even though they account for only 20 percent of state water consumption.Lucy Nicholson—Reuters
A canal runs through farm fields in Los Banos
Approximately 9 million acres of farmland in California are irrigated, representing roughly 80% of all human water use. But, farm production and food processing only generate about 2% of California’s gross state product, down from about 5% in the early 1960s.Lucy Nicholson—Reuters
"In the Central Valley, where most agricultural water use occurs, the failure to manage groundwater sustainably limits its availability as a drought reserve. The increase in perennial crops—which need to be watered every year—has made the region even more vulnerable," the Public Policy Institute of California states.
"In the Central Valley, where most agricultural water use occurs, the failure to manage groundwater sustainably limits its availability as a drought reserve. The increase in perennial crops—which need to be watered every year—has made the region even more vulnerable," the Public Policy Institute of California states. Lucy Nicholson—Reuters
Water pours into a canal in Los Banos
Central Valley farmers have witnessed land sinking by as much as 3 feet, San Francisco Gate reports, as water agencies tap underground reservoirs at unprecedented depths. Water pours into a canal in Los Banos, Calif., May 5, 2015. Lucy Nicholson—Reuters
Livestock products, including meat, dairy and eggs, account for more than a quarter of California's agricultural sector, a $12.5 billion industry, according to the USDA. Cattle are among the most water-hungry livestock, consuming an average of106 gallons per pound of beef. Cattle are seen at Harris Ranch in Coalinga, Calif. on May 5, 2015.
Livestock products, including meat, dairy and eggs, account for more than a quarter of California's agricultural sector, a $12.5 billion industry, according to the USDA. Cattle are among the most water-hungry livestock, consuming an average of106 gallons per pound of beef. Cattle are seen at Harris Ranch in Coalinga, Calif. on May 5, 2015. Lucy Nicholson—Reuters
A wheat field is seen in Los Banos
California's planting of staple crops such as cotton, corn, oats, barley, wheat, rice, and sunflowers will total 1.72 million acres in 2015, down from 1.90 million acres in 2014, according to data from the National Drought Mitigation Center. A wheat field is seen in Los Banos, Calif. May 5, 2015. Lucy Nicholson—Reuters
A water protest sign is seen in Los Banos
A water protest sign is seen in Los Banos, California, United States May 5, 2015. Central Valley counties suffer some of the highest unemployment rates in the state, topping out at more than 20% in Colusa County, according to the state's Legislative Analyst's Office.Lucy Nicholson—Reuters

Widespread tree death can be described as a 20-year “sequence of flammability,” Covington said. First, dead needles on pine trees dry up and start a period of “extreme fire danger.” When the needles fall to the ground, they remain extremely vulnerable to catching fire but are less likely to spread. Finally, over the years, the trees fall to the ground. If they catch fire, have the potential to destroy the surrounding soil and destabilize the habitat.

Other factors contributing forest fire risk include an increase in the presence of various invasive species that wreck havoc on the local environment and poorly located hazardous fuels.

When the Forest Service isn’t focused on fighting wild fires, agency officials spend time and resources trying to prevent the possibility of future fires through ecological restoration, a process of restoring an ecosystem to its natural state. The process doesn’t prevent fires, but it makes them less likely to grow to massive proportions.

Forest Service workers have treated more than 9,300 acres thus far this year, but Covington says it’s not enough. Ecological restoration projects should aim to handle hundreds of thousands or millions of acres to be most effective, he says.

“The science strong is on this,” Covington said. “Ecological restoration will not only prevent severe fires, but all bring in the way of resource benefits for wildlife, for watershed conditions, for scenic beauty and even possibly some restoration jobs.”

The Most Beautiful Wildfire Photos You'll Ever See

Yosemite Meadow Fire Wildfire
The Meadow Fire burns overnight near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained. Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns at dawn near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained. Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns overnight near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained. Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns overnight near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained. Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns at dawn near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained.Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns at dawn near Half Dome in Yosemite National Park early Monday September 8, 2014 as rain moves in from the south. As of Wednesday the fire had burned over 4,500 acres and was 10% contained.Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns overnight near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained. Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns at dawn near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained.Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns overnight near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained. Stuart Palley
Yosemite Meadow Fire Wildfire
The Meadow Fire burns at dawn near Half Dome in Yosemite National Park early Monday September 8, 2014. As of Wednesday the fire had burned over 4,500 acres and was 10% contained. Stuart Palley

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Write to Justin Worland at justin.worland@time.com