What, Besides Climate Change, Caused the California Wildfires?

 In NSW, State

Despite some progress made by heroic fire­fight­ers, wild­fires con­tin­ue to tear through the West. Tragically, the fires have taken more than 30 lives (with many more miss­ing), destroyed thou­sands of struc­tures, and burned mil­lions of acres.

Here are answers to some of the com­mon­ly asked ques­tions on causes for the wild­fires and obsta­cles that stand in the way of solu­tions.

What caused the wild­fires?

At least sev­er­al fac­tors. At the end of August, a storm with a lot of light­ning and little rain struck. An esti­mat­ed 11,000 lightning strikes hit California over a three-day span, spark­ing fires through­out the state.

More recent­ly, two of the fires start­ed because of hot soot from a car tailpipe and a family using a “smoke-generating pyrotechnic device” for a gender reveal party. One man in Oregon has been charged with arson.

Investigations con­tin­ue into the causes of some of the fires. In the past, camp­fires, dis­card­ed cig­a­rettes, fallen power lines, and arson have been the cul­prit.  

Despite accu­sa­tions that extrem­ists on both the left and right set cer­tain wild­fires, nei­ther has been the case. In fact, false rumors have served only to spread resources thin­ner and detract from seri­ous inves­ti­ga­tions.

Are these fires the worst ever? Are wild­fires more fre­quent and destruc­tive?

The more than 3.2 mil­lion acres burned thus far in California are the most in record­ed his­to­ry.

According to the California Department of Forestry and Fire Protection, data over the past 30 years shows that the number of fires is on a down­ward trend while the number of acres burned is on an upward trend.

However, as Mother Jones reports, ecol­o­gists and fire sci­en­tists esti­mate that pre­his­toric fires were worse, burn­ing between 4.4 mil­lion and 11.8 mil­lion acres per year.

On a nation­al scale, data from the National Interagency Fire Center shows a downward trend for both fires and acres burned from 1926 through 2019, though report­ing meth­ods dif­fered before 1983.

Why have the wild­fires been so severe?

California is a hot and dry place. The winds can be fierce this time of year and the steep slopes of the topog­ra­phy can make them prac­ti­cal­ly unstop­pable.  Although the winds come every year, they’re also unpre­dictable.

Alexandra Syphard, an ecol­o­gist at the Conservation Biology Institute, noted that “wind-driven fires are the ones most asso­ci­at­ed with cat­a­stroph­ic losses” because of their difficulty to contain and propensity to reach places where people live.

Then there’s the fuel load. Without proper man­age­ment, whether pre­scribed burns or timber har­vest­ing, California is a tinder box com­prised of dry trees, grass, and shrubs. Invasive species, includ­ing grass­es and shrubs, also contribute to worse wildfires because they dry out and have a higher like­li­hood of burn­ing than native plants.

Better land man­age­ment long has been under­stood as a neces­si­ty to reduce the sever­i­ty of fires. Malcolm North, of the U.S. Forest Survey, says: “Climate dries the [wood] fuels out and extends the fire season from four to six months to nearly year-round. [B]ut it’s not the cause of the inten­si­ty of the fires. The cause of that is fire sup­pres­sion and the exist­ing debt of wood fuel.”

Timothy Ingalsbee, exec­u­tive direc­tor for Firefighters United for Safety, Ethics, and Ecology, told ProPublica: “We need to get good fire on the ground and whit­tle down some of that fuel load.”

If con­trolled burns and thin­ning forests are effec­tive, why are they so hard to do?

California’s fuel load has been a long-stand­ing, wors­en­ing prob­lem and a top pri­or­i­ty for ecol­o­gists and land man­agers who want to reduce the sever­i­ty of wild­fires.

Jon Keeley, senior sci­en­tist at the U.S. Geological Survey’s Western Ecological Research Center, said: “We ought to be much more con­cerned with igni­tion sources than a 1- to 2‑degree change in tem­per­a­ture.”

Prescribed burns (see photos here) are an effec­tive, non-controversial way to reduce the fuel load and con­se­quent­ly reduce the destruc­tion caused by a wild­fire. Fires also help  to con­trol pests, to remove non-native plants, and to pro­vide nutri­ents to trees and other veg­e­ta­tion.

As the nar­ra­tor says in this National Geographic video: “Giant sequoias depend on fire to repro­duce. The heat opens their seed cones, their seeds are released, the flames clear the earth for their ger­mi­na­tion. While lesser trees blaze around them, the giant sequoias stand vir­tu­al­ly unscathed by the flames.”

Studies have shown that these pre­scribed burns do not harm the ecol­o­gy of the forest. California has imple­ment­ed con­trolled burns for an aver­age of 13,000 acres from 1997 to 2017. But a February arti­cle in the jour­nal Nature Sustainability suggests that California needs about 20 mil­lion acres burned.

Controlled burns are by no means a silver bullet, but an over­whelm­ing con­sen­sus exists among land man­agers that such burns are the most imme­di­ate and effec­tive action to take.

As for why that hasn’t hap­pened, the same arti­cle in Nature Sustainability breaks it down to three cat­e­gories: risk, resources, and reg­u­la­tion.

Some have concerns about the smoke from con­trolled burns, and that the fires may get out of con­trol; others have con­cerns over lia­bil­i­ty should that occur. Even so, the prac­tice large­ly has won public acceptance.

Another bar­ri­er is pre­sent­ed by weath­er and loca­tion. Controlled burns take into account ideal humidity ranges, as well as wind direction and speed. Some con­trolled burns occur where there are power lines or pipelines, which require addi­tion­al atten­tion. COVID-19 post­poned many of the pre­scribed burns.

Regulation presents a major obsta­cle. Prescribed burns go through a lengthy approval process. Securing a permit can take up to 18 months.  These burns are subject to the National Environmental Policy Act and must meet federal, state, and local air quality standards.

Of course, the pol­lu­tion and air qual­i­ty is much worse from the wild­fires than from a con­trolled burn. Even when a plan seem­ing­ly checks all the nec­es­sary boxes, it still may be held up in the courts. Although some progress has occurred to expe­dite the process, more needs to be done.

Another solu­tion is timber har­vest­ing, which helps thin the land­scape and put those resources to pro­duc­tive use.

What is the role of cli­mate change?

It stands to reason that as the planet warms, the American West will become drier and states’ wild­fire sea­sons will be longer. The planet has been in a warm­ing period for the past 160 years, and part of that warming is a result of human activ­i­ty.

One study out of UCLA esti­mates that the number of days with extreme fire weath­er in the fall has more than dou­bled over the past 40 years. Another study in Earth’s Future found sim­i­lar results for warming’s effect on fuel drying, but noted that a chang­ing cli­mate has not affect­ed wind or pre­cip­i­ta­tion pat­terns:

In fall, wind events and delayed onset of winter pre­cip­i­ta­tion are the dom­i­nant pro­mot­ers of wild­fire. While these vari­ables did not change much over the past cen­tu­ry, back­ground warm­ing and con­se­quent fuel drying is increas­ing­ly enhanc­ing the poten­tial for large fall wild­fires.

Cliff Mass, a pro­fes­sor of atmos­pher­ic sci­ences at the University of Washington, empha­sizes that even with­out the warm­ing that is occur­ring, fuels are “plenty dry enough to burn already.”

Soil mois­ture is anoth­er factor that can determine how severe a wild­fire might be. Last year, in a very mild season, soil mois­ture in California was 40% above average for most of the state and even higher in some parts.

Droughts can be both bad and good. Droughts obvi­ous­ly create a dry cli­mate for veg­e­ta­tion to burn, but extend­ed droughts can result in less fire because, as NASA’s Ben Cook points out, “the veg­e­ta­tion will not grow back as vig­or­ous­ly, and you may run out of fuel to burn.”

Some parts of California, such as the area where the Camp Fire wild­fire occurred in 2018, saw no dis­cernible trend in fuel mois­ture or pre­cip­i­ta­tion, but the winds were strong enough to dry out the veg­e­ta­tion anyway. 

Which brings us to anoth­er point of the dis­cus­sion: how cli­mate change affects wind pat­terns. California is known for intense winds, such as the Diablo winds in the north and the Santa Ana winds in the south.

Several studies show that warm­ing actu­al­ly could reduce the frequency of the Santa Ana winds and poten­tial­ly weaken the pressure of Diablo winds. If pre­cip­i­ta­tion pat­terns change, how­ev­er, that merely might push the wild­fire season from the fall into the winter.

That’s to say that the link between cli­mate change and wild­fires exists, but it also is quite com­plex.  

What about where we live, and hous­ing poli­cies?

Residents of the West are moving to more fire-prone areas. The New York Times pod­cast “The Daily” explains that this is called the Wildland Urban Interface, where devel­op­ment meets wild veg­e­ta­tion.

People choose to live in more rural areas for a host of rea­sons. They may want to be closer to nature and where houses are more afford­able. The higher number of homes and busi­ness­es in these areas also increas­es the like­li­hood of a human-induced fire and puts more lives and struc­tures at risk. These threats as they per­tain to the Wildland Urban Interface are not spe­cif­ic to California, but exist in many places around the coun­try.

National Interest source|articles

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