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The Firestorm This Time: Why Los Angeles Is Burning (wired.com) 231

The Thomas Fire spread through the hills above Ventura, in the northern greater Los Angeles megalopolis, with the speed of a hurricane. Driven by 50 mph Santa Ana winds -- bone-dry katabatic air moving at freeway speeds out of the Mojave desert -- the fire transformed overnight from a 5,000-acre burn in a charming chaparral-lined canyon to an inferno the size of Orlando, Florida, that only stopped spreading because it reached the Pacific. Several readers have shared a Wired report: Tens of thousands of people evacuated their homes in Ventura; 150 buildings burned and thousands more along the hillside and into downtown are threatened. That isn't the only part of Southern California on fire. The hills above Valencia, where Interstate 5 drops down out of the hills into the city, are burning. Same for a hillside of the San Gabriel Mountains, overlooking the San Fernando Valley. And the same, too, near the Mount Wilson Observatory, and on a hillside overlooking Interstate 405 -- the flames in view of the Getty Center and destroying homes in the rich-people neighborhoods of Bel-Air and Holmby Hills. And it's all horribly normal. [...] Before humans, wildfires happened maybe once or twice a century, long enough for fire-adapted plant species like chapparal to build up a bank of seeds that could come back after a burn. Now, with fires more frequent, native plants can't keep up. Exotic weeds take root. Fires don't burn like this in Northern California. That's one of the things that makes the island on the land an island. Most wildfires in the Sierra Nevadas and northern boreal forests are slower, smaller, and more easily put out, relative to the south. Trees buffer the wind and burn less easily than undergrowth. Keeley says northern mountains and forests are "flammability-limited ecosystems," where fires only get big if the climate allows it -- higher temperatures and dryer conditions providing more fuel. Climate change makes fires there more frequent and more severe.

The Firestorm This Time: Why Los Angeles Is Burning

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  • by rmdingler ( 1955220 ) on Thursday December 07, 2017 @09:12AM (#55694673) Journal
    There are ideal conditions for wildfires in this region (and others) nearly every year. What's special about this year?

    "What we don’t have every single year is an ignition during a wind event. And we’ve had several."

    Whether by foolish acts or (pyro)maniacal disposition, people are the blight on this land.

  • True (Score:3, Funny)

    by 110010001000 ( 697113 ) on Thursday December 07, 2017 @09:25AM (#55694747) Homepage Journal
    There were never wildfires before climate change was discovered.
    • by Mashiki ( 184564 )

      Very true. I remember being in Banning, California back in the late 1980's with my parents and seeing the mountains burning. Back then they called it a seasonal burn, now it's wildfires due to climate change.

    • Re:True (Score:5, Interesting)

      by Gravis Zero ( 934156 ) on Thursday December 07, 2017 @12:49PM (#55696449)

      There were never wildfires before climate change was discovered.

      The is real problem is that we're been putting out the wildfires for over a hundred years when burning is part of the natural cycle of life for the ecosystem. As a result there are many millions of dead and dry trees just waiting for a spark. [sfgate.com] However, climate change is exacerbating the issue by causing more extreme weather (longer droughts and more extreme downpours) which ultimately kill more plants and turn them into fuel for the fire. Climate change definitely isn't the cause of these giant wildfires but it is making it worse.

    • Only if you promote false dichotomy arguments and don't bother to read even the summary: "Climate change makes fires there more frequent and more severe."
  • California has had droughts lasting up to 500 years.

    Just a coincidence that the last 500 years in California were wetter than normal.

    • Think DUST BOWL..

      The history of that man made disaster is rife with the same kind of things they say today, just in reverse.

      Nobody wanted to believe that the pan handle of Texas was really a dry desert, unstable for farming. Yea, a decade of rainy weather tricked a bunch of people to plow up thousands of acres of land, year after year, thinking that the rain would return, only to watch their fields blow away as dust.

  • by xxxJonBoyxxx ( 565205 ) on Thursday December 07, 2017 @09:30AM (#55694773)
    >> higher temperatures and dryer conditions providing more fuel

    I thought you needed WETTER conditions to get more fuel. Is anyone surprised that there are a bunch of large fires after California's water supply returned to normal and plants had a chance to grow back? (It was as green along Hwy 1 as I've ever seen it this year.) That stuff dries out...and then burns - science, yo.

    http://www.mercurynews.com/2017/10/03/will-this-winter-in-california-be-wet-or-dry/
    • by tsqr ( 808554 )

      >> higher temperatures and dryer conditions providing more fuel I thought you needed WETTER conditions to get more fuel. Is anyone surprised that there are a bunch of large fires after California's water supply returned to normal and plants had a chance to grow back? (It was as green along Hwy 1 as I've ever seen it this year.) That stuff dries out...and then burns - science, yo. http://www.mercurynews.com/201... [mercurynews.com]

      Yeah, that was poorly worded. Higher temps and low humidity turn the abundant growth into more explosive fuel.

      At least with the current rash of fires, firefighters haven't had to contend with extremely high temperatures; we've had highs in the low 70s all week.

    • by dfm3 ( 830843 ) on Thursday December 07, 2017 @10:44AM (#55695279) Journal
      TFA does a better job than the summary at explaining, but yes, your observation is consistent. Wetter summers mean more vegetation growth, but it's the weather during a few critical weeks in late fall that determine how severe the fires will be.

      It's the small stuff (leaves, brush, and weeds) that burns fast, hot, and explosively given the right conditions. In the fall, when the deciduous species lose their leaves, a wet December means that most of this vegetation falls to the ground and begins to decompose, rendering it more dense and less flammable. When you have a combination of dry weather, warm temperatures, and high wind, combined with ignition (historically caused by lightning, but usually by people these days), leaves tend to stay on the trees longer, or fall to the ground without decomposing, and become perfect fuel.

      So yes, you're correct that when this stuff dries out, it becomes a hazard.

      For example, last fall was a historically notable fire season in the southern Appalachians. Many parts of the mountains in NC/TN/GA had little to no measurable rainfall for a couple months, so the leaves simply dried up and stayed on the trees rather than changing color and falling to the ground. The deadly fires that swept through Gatlinburg, Tennessee [wikipedia.org] became "canopy" fires - an event more common in California but virtually unheard of in eastern forests. Even one good rainstorm could, in theory, have been sufficient to knock enough leaves off of the trees and compress the leaf litter on the forest floor to render it slightly less flammable.
  • Fires don't burn like this in Northern California.

    I guess this guy must have been asleep a few months ago when the Tubbs fire burned nearly 40,000 acres, destroyed nearly 6,000 buildings, and killed over 40 people In and around Santa Rosa, CA.

  • that's why...

  • Me, I find a use now and then for water falling from the sky.
  • There was also another fire recently east of Burbank threatening wealthy home owners.

    It seems too coincidental that another fire just happened to appear in another very wealthy neighborhood during one of the windiest days this year.

    • All it takes is a careless dipshit flicking a cigarette butt out the window. Oh but you didnt pay attention to the 241 toll road fire a couple months back, did you?

      Refrain from speaking until you actually have a clue.

  • It's surprisingly competent and literate, especially for Slashdot.

  • "Before humans, wildfires happened maybe once or twice a century"

    Really?

    Brandolini's Law: The amount of energy needed to refute bullshit is an order of magnitude bigger than to produce it.
  • by eepok ( 545733 ) on Thursday December 07, 2017 @11:22AM (#55695567) Homepage
    Every big stretch of wildfires are caused by the same thing:

    1. High winds
    2. Low humidity
    3. Unmanaged brush
    4. Either a lightning storm or (more likely) some human doing something stupid (camp/bonfire, trash burning, arson, cigarette, etc.)

    This year was particularly bad for both Northern and Southern California because this past winter's rain was so significant that it almost completely erased the multi-year drought. That means lots and lots of greenery growing in the spring and waiting to burn throughout the summer and fall.
  • by gurps_npc ( 621217 ) on Thursday December 07, 2017 @11:28AM (#55695641) Homepage

    1) We have been ignoring the fire risk for a long time. Specifically we have stopped all small fires before they get anywhere, which means there are a lot fuel wood stocked up. The smarter thing to do is to let small fires become controlled medium sized fires during the WET season, rather than the dry season when they become huge.

    2) We have been putting houses in stupid locations and not requiring appropriate fire prevention measures. There is nothing wrong with building a house in the middle of fire zones. But make it a bunker out of concrete. Yes, it won't look the same as a normal house, so freaking what? A good architect can make a concrete, fire-proof home still look good. Yes it costs more. But less than double, which is what most people will pay.

    3) Oh yeah, and stop counting fire smoke from intentionally set preventative fires as 'pollution' while saying that smoke from natural forest fires doesn't count because it isn't man made.

    • by Miamicanes ( 730264 ) on Thursday December 07, 2017 @12:16PM (#55696099)

      If the current fires encountered a large expanse of concrete devoid of anything directly combustible, how wide would it have to be to actually stop the fire's spread?

      As I understand it, once uncontrolled outdoor fires reach a certain size, they act kind of like weak tornadoes that lift flaming objects high into the air & hurl them out to areas that might be several thousand feet away (enabling the fire to jump over thing like freeways, canals, etc).

      If a house in the middle of an affected neighborhood had reinforced concrete walls & roof, plus Miami-grade impact-glass windows, would the heat of the fire as it burned down the neighbors' houses cause the concrete house's interior to combust anyway (like food debris in a self-cleaning oven)? Would ICF construction plus roll-down steel shutters keep the interior cooler, or would the intense heat just cause the ICF styrofoam itself to melt or combust?

      I know that conventional wisdom is that individual homeowners are helpless against a fire, but I remember reading about one guy in California a few years ago who put sprinklers on his roof & surrounding yard, connected them to the faucet, and left it running when he evacuated. When he got home, his home had major "baking" damage... but his neighbors' homes were literally burned down to the scorched earth. I think some local official later decided to be a dick & fined him $10,000 for violating water-conservation rules to discourage others from trying to do it in the future.

      • by dgatwood ( 11270 )

        If a house in the middle of an affected neighborhood had reinforced concrete walls & roof, plus Miami-grade impact-glass windows, would the heat of the fire as it burned down the neighbors' houses cause the concrete house's interior to combust anyway (like food debris in a self-cleaning oven)? Would ICF construction plus roll-down steel shutters keep the interior cooler, or would the intense heat just cause the ICF styrofoam itself to melt or combust?

        That depends on how thick the material is and how far

  • California had a wet winter this year, with some parts receiving near record amounts of precipitation. That contributed to a very green spring, which inevitably leads to a fierce wildfire season. As to the degree that climate change contributed to it is debatable.

    California is also suffering from the spread of invasive, highly flammable non-native grasses. These grasses are often the first to recover after a burn, so less flammable native plants get pushed out. This is contributing to more frequent, mor

  • I live and work near it. Well, for certain values of near.

    I live 5 miles from it, and work about 10 miles from it.

    So far, at least three coworkers that I know (and probably a few more that I don't know) have lost houses to it.

    Air quality is currently at about .75 LB (that is, 3/4 of Long Beach, where every day is a pack of filterless Lucky Strike 100s).

  • The big fire is in Ventura County, not Los Angeles and not Los Angeles County. There are other fires in Los Angeles County, but the biggin is north west of LA County.

    Next you'll tell me JPL is in Pasadena or that the Statue of Liberty is in New York. (And then you'll fucking redraw the map to make it so.)

  • The wildfires in the area are a recurring natural phenomenon, what is *abnormal* is humans developing the area and trying to prevent the normal and expect recurring wildfires.

    And of course the number has been declining for decades:
    http://www.ocregister.com/2017... [ocregister.com]

  • ..we have all the conditions for some terrible bushfires. But where I live in WA we do regular burnoffs during the wet season. In the east they're filled with hippie tree hugging fuckwits that don't like their precious environment getting destroyed by burnoffs, so they let the fuel build up around them, then promptly lose their houses.

    I'm guessing theres a similar amount of bleeding hearts for small animals in southern california. Let them burn.

    • It's also a population issue: Entire population of Australia: 24 million. Entire population of California: 39 million.

  • I grew up in Southern California. It's a desert with brush growing when rain allows it. Increased population pushing out into the desert means more chances of accidental fire. Add in a windy season, as we've always had, and it burns. It burns every year. Always. this year is worse because of the winds sticking around longer, but yeah: wind=fire for the most part in California.

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