“Extreme temperatures of 100+ degrees will combine with very low relative humidity. This will create conditions that are favorable for increased fire growth.”
“There was good overnight humidity recovery in the fire area last night, which will delay the burn period today. However, as temperatures warm and vegetation dries out, pockets of heat may become more active in the afternoon.”
These excerpts from the incident reports of the Sherpa Fire in California and the Dog Head Fire in New Mexico, respectively, highlight the relationships between weather and wildfires. Over the past few decades, climate change has driven an inexorable trend of higher summer temperatures across the West—a trend that is expected to continue for years to come. This year, some states may see relief if the El Niño pattern shifts rapidly to La Niña—and if Congress passes legislation that provides sufficient resources to manage wildfire risk effectively.
Hot enough for ya?
Temperatures on Father’s Day tied the record high temperature of 103 degrees in Albuquerque, New Mexico, further contributing to the heat fueling the Dog Head Fire raging nearby, and making conditions miserable for firefighters.
With the fire exceeding 17,000 acres and only 9 percent contained, Governor Martinez declared a state of emergency and mobilized the National Guard. Fortunately, on Monday, weather conditions began to change, with higher humidity moving into the area, bringing peak temperatures down into the upper 90s (!) and allowing firefighters to improve their fire lines. But this was cold comfort to the owners of the two dozen homes that had already been lost to this fire.
Meanwhile, another fire was blazing near Santa Barbara, California—the Sherpa Fire. By Monday, it had burned nearly 8,000 acres and was more than 50 percent contained. More than 1,200 firefighters worked night and day, preparing to defend fire lines in the midst of an excessive heat warning, with maximum temperatures exceeding 100 degrees. “Sundowner” winds were expected to blow from the Santa Ynez Mountains at speeds up to 40 miles per hour in the evening, potentially fanning the flames overnight. Already several communities had been evacuated, and Highway 101 had been closed at times.
These were just two of the 16 active fires burning over the weekend, which had consumed a total of nearly 100,000 acres. The problem is not limited to the West – brushfires in Florida closed a major highway early in the week – but the Western states are where we’ve seen the most fires breaking out. And the wildfire season is just getting started, and might be worsened by the climate phenomena known as El Niño and La Niña.
El Niño and La Niña: Children shouldn’t play with fire
I’m often asked how El Niño and La Niña affect wildfires in the West, and the answer is complicated.
On top of the rising temperature trend driven by climate change, we have other patterns that affect global temperatures. El Niño and La Niña (“the boy” and “the girl” in Spanish, respectively) are used to describe a pattern of global climate conditions that tend to alternate every few years.
Among other features, El Niño is characterized by warmer-than-normal water in the eastern Pacific, which tends to bring more moisture and precipitation to the southwestern US and leaves the northern tier of states hot and dry. In contrast, La Niña exhibits cooler waters in the eastern Pacific, leading to drier conditions in the Southwest, while wetter conditions prevail in the Pacific Northwest and the northern Intermountain West.
Last year we were in the midst of a powerful El Niño—possibly the strongest measured since 1950. And, as we would expect, the Northwest was abnormally hot and dry, setting the stage for a record-breaking wildfire year, with over 10 million acres burned in the US.
The effects of El Niño lingered through the spring in most places, bringing record heat to the Southwest, but failed to provide much-needed moisture to southern states, including California, Arizona, and New Mexico. As a result, southern California is still suffering through an extreme drought, estimated to be affecting more than 33 million people. It should come as no surprise, then, to see wildfires breaking out in the hottest, driest areas.
Climate scientists are now saying there is a strong likelihood that the El Niño conditions could rapidly flip to La Niña conditions by autumn. If La Niña follows its usual pattern, it may bring some relief to the Pacific Northwest, Alaska, and the northern Intermountain states.
Unfortunately, it could also exacerbate the dry conditions in the Southwest, prolonging the drought in California and potentially expanding it to other states. On top of the drought, if the record-breaking heat of June is a sign of a hot summer to come, we could see another extraordinary fire season—putting many communities at risk and stretching our capacity to cope.
Congress has taken notice – but will it act in time?
Policy makers have taken notice of the situation, and some are working to help us become better prepared for wildfire risks. It’s a complex problem to solve, with several factors involved.
First, decades of fire suppression have led to a buildup of flammable materials—living and dead trees, litter, grasses, etc.—in many areas, and these materials act as tinder once a fire starts.
Second, the warmer and drier conditions have spurred a wave of tree mortality in Western forests, accelerated by climate change, leaving dead trees that are vulnerable to fire.
Third, more people have moved into forested areas, putting themselves and their property in harm’s way, and making fire suppression more costly because firefighters spend more time and effort protecting developed areas.
And fourth, we have climate change itself creating conditions that increase the likelihood and extent of wildfire.
The Forest Service, which is responsible for managing 193 million acres of public land, primarily in the West, has been grappling with this problem as it unfolds. Administrators have recognized that recent fire seasons are regularly breaking their budgets, perversely forcing them to take money budgeted for fire risk reduction activities and use it for fire suppression instead.
After a collective face palm, Congress began to put together legislation aimed at fixing this problem. The latest bipartisan draft legislation in the Senate is called the Wildfire Budgeting, Response, and Forest Management Act of 2016. A hearing on the draft legislation is expected in the Senate Committee on Energy and Natural Resources on Thursday, June 23. The hearing is organized around two panels of witnesses, representing a range of government, private sector, and civil society viewpoints. It should be an informative discussion.
Regardless of whether this legislation moves forward or not, the wildfire problem is not going away.
Year by year, the factors contributing to wildfire risk continue to increase—with climate change potentially becoming the most important factor of all.
Hopefully Congress will pass legislation that can help us get a better handle on fire-fighting and land management to control the risk of wildfires for the next few years. Maybe some of us will get a break from La Niña or some other short-lived phenomenon. But ultimately these fixes will be temporary, unless we can stop the inexorable rise in global temperatures by reducing our emissions of heat-trapping gases. And on that point, Congress has yet to take any serious action.
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