LANL developing software to better manage prescribed burns

May 22—Intentionally setting a fire in a wooded area during a severe drought in a state where winds can be difficult to predict comes with risk.

But prescribed burns have become a standard way to reduce flammable debris, overgrown vegetation and trees crowded together to avoid a catastrophic blaze within forests where crews for decades extinguished natural fires that would've thinned these fuels.

Los Alamos National Laboratory is developing a modeling tool that will aid fire managers in making prescribed burns more of an exact science.

Known as QUIC-Fire, the software is designed for portable devices such as a laptop computer, making it practical for teams to use in the field.

Managers already gauge suitable times for lighting controlled fires based on factors such as temperature, humidity, wind speed and direction, terrain, moisture content in fuels and the density of vegetation.

QUIC-Fire can run hundreds, even thousands, of simulations in a short time. Those give agencies a far greater idea of how a fire might behave and the possible outcomes, so they can manage the burn better, know the risks and can decide whether they should even ignite a fire that day.

"They're doing their best to weigh all these different conditions and understand when they can burn safely," said Rod Linn, a lab scientist involved in developing the program. "What we're trying to do is provide a greater science basis to assist with that decision process."

The monstrous Hermits Peak/Calf Canyon Fire, which has scorched more than 300,000 acres and destroyed at least several hundred homes, shows the importance of ensuring a controlled fire remains just that.

On April 6, U.S. Forest Service crews were conducting a prescribed burn northwest of Las Vegas, N.M., when unexpected afternoon gusts blew the flames over the fire line.

Two weeks later, as teams were about to contain this fire, fearsome winds stoked it and the nearby Calf Canyon Fire. The two fires merged April 23 and swelled into the mammoth blaze that is still raging.

Gov. Michelle Lujan Grisham has urged the federal government to take accountability for the fire and cover 100 percent of the costs associated with the response and recovery efforts. On Friday, she praised the Forest Service's decision to put a temporary halt on prescribed burns.

In a statement issued Friday, Forest Service Chief Randy Moore said the agency will conduct a 90-day national review of its prescribed burn policies.

"In 99.84 percent of cases, prescribed fires go as planned," Moore said in the statement. "In rare circumstances, conditions change, and prescribed burns move outside the planned project area and become wildfires."

QUIC-Fire, which is in the testing phase, will not only help managers assess the complex array of conditions they face when planning a controlled burn, it will give them a more precise reading of the landscape so they can form strategies to achieve their goals, whether it's reducing fuels or enhancing the ecology, Linn said.

Prescribed burns are a more intricate task than most people would imagine, he added. For instance, managers must determine the rate of ignition and the configuration of the fire lines according to terrain, fuels and wind.

So it's not just deciding when to ignite the fire but how, he said.

The program draws from databases such as FastFuels to generate 3D pictures, with sharp resolution, of the area where a prescribed burn might be considered, Linn said.

"So, it's capturing individual trees, and the spacing between trees, and the space between the surface fuel and the trees," he said, "which are all very critical for fire behavior."

A wider range of fire modeling will become crucial as climate change disrupts historic weather patterns, leading to more arid conditions and inconsistent rainy seasons, according to an article in the lab's publication 1663.

The Forest Service and U.S. Fish and Wildlife Service are field testing QUIC-Fire, mainly in California and Southeastern states, Linn said. It's unknown when the software could become available for agencies' practical use everywhere, including New Mexico, he said.

"This is the first tool really targeted at prescribed fire," said Scott Goodrick, who heads the Forest Service's Center for Forest Health and Disturbance.

Goodrick said he and Linn teamed up to create a program to help managers plan for prescribed burns.

He agreed a big part of what the software offers is logistical aid. Whether crews are igniting spot fires on the ground or from the air, you want the various fire lines to intersect in the right spots and with the right intensity to prevent the burn from going awry, he said.

QUIC-Fire gives a more thorough picture of the conditions, both on the ground and in the atmosphere, to guide the fire strategies, Goodrick said.

Neither Goodrick nor Linn would comment specifically on the prescribed burn that went out of control and caused the Hermits Peak Fire.

"I would hesitate to say that QUIC-Fire could predict the exact events that happened on that fire," Goodrick said.

However, the program, which runs a slew of potential outcomes, will enable a manager to look at the more extreme possibilities, such as the likelihood a prescribed burn could turn into a catastrophic fire, Goodrick said, noting risk assessment is a key function.

If the chances of a huge runaway fire are less than 1 percent, a supervisor probably would feel safe proceeding, he said. If the risk is 10 percent, then probably not.

Some of the modeling is based on past fires that researchers recreated for the program, and so far it mostly matches what managers observed at those fires, Goodrick said.

"The program is producing stuff that the managers have some level of confidence in," he said. "They're seeing [fire] behaviors they've seen in the field before."

If there's a marked difference between a simulation and a real fire, it's because researchers didn't account for a variation such as a marshy patch or a knoll where the vegetation is drier, he said.

In those instances, the simulations are tweaked, Goodrick said.

Linn said another valuable piece of the modeling is preparing fire managers to react effectively if things don't go as initially planned — for instance if the winds turn chaotic.

"To help them understand how sensitive the fire might be to the expected range of wind conditions," Linn said. "Or maybe to help them understand there are risks under certain weather conditions and allow them to develop contingency plans."