GNF & World War II & Apocalypse & Science & WAAGNFNP Posted by James Killus, 23 Oct 2007 06:22 am
Firestorms
[Note: In light of the enormity of the firestorms happening in Southern California, we are reposting James’ Firestorms for those who missed it previously, or who have something more or new to say. And we send our very best wishes to those suffering from and fleeing from the flames.
-Oaktown Girl, Minister of Justice, WAAGNFNP]
So fires always produce an updraft. In truly big fires, the question becomes how the updraft interacts with the local weather. If the local winds are stronger than the updraft, and the fire is big, uncontrolled, and uncontained, you have a conflagration. If the fire creates its own winds, you have a firestorm.
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If you try to light a match under micro-gravity conditions (we all got used to “zero-g” so some smarty pants had to go and call it “micro-gravity”) and just hold it in one place, it will self-extinguish. The match will use up enough of the oxygen in its surrounding volume of air to extinguish the flame. It doesn’t have to use up all the oxygen, either; most flames go out in air that still has enough O2 in it for people to breathe—barely.
Depending on the fuel, (e.g. hydrogen needs less oxygen to burn than methane does), the usual figure given is that 14%-16% oxygen is needed to sustain a fire. People can manage on a bit less; Biosphere II dropped below 14% before they pumped in some additional O2, but they didn’t have to contend with elevated CO2 levels; in fact, what they’d been losing was CO2, by absorption into their nice new concrete structure, with bacteria converting soil organics and O2 into CO2. They’d had a bit of a “slow burn.”
Your basic candle flame is fed fresh air by gravity, specifically, the air coming in to replace the hot gases that have become lighter than air in the hot flame. That’s called the “fire draft” and fireplaces exist to direct the fire draft upwards, so the smoke doesn’t choke the people warming themselves by the fire. The chimney/flue of the fireplace also accelerates the fire draft if you build it right, and both Ben Franklin and Benjamin Thompson, (Count Rumford), invented some tricks that are still in use.
So fires always produce an updraft. In truly big fires, the question becomes how the updraft interacts with the local weather. If the local winds are stronger than the updraft, and the fire is big, uncontrolled, and uncontained, you have a conflagration. If the fire creates its own winds, you have a firestorm.
Neither is anything you or I want to be near. A running wildfire can exceed 70 mile per hour under upslope flow conditions, where the fire draft adds to the natural winds. Firestorms generate their own weather, their own winds, and can create small tornadoes, “dust devils” made out of flaming gases that light everything they touch.
The heat in the interior of a firestorm pyrolizes everything within its boundaries, but the fuel produced exceeds the air available. So the hot mass rises as a fireball, sucking more air into it, maintaining its heat even as it expands, because there is still plenty of fuel gas left to burn. A firestorm spreads as much by thermal radiation as by flaming contact, sometimes triggering fires at a distance, like across a valley.
Kurt Vonnegut lived through the firebombing of Dresden, and wrote about it, so more people know about the 35,000 people who died there than in Operation Gomorrah, which killed a larger number (50,000 est.) in Hamburg, or the 120,000 who died in the Tokyo fire raids. I’d never even heard of the raids on Kassel, Braunschweig, Darmstadt, Heilbronn, Pforzheim, and Würzburg until I looked them up for this essay.
But fires are tricky to set with conventional incendiaries. Most of the WWII fire raids were duds, or semi-duds, producing some fires, but nothing like a real firestorm. There were four attempts on Hamburg before they hit the jackpot.
But Hiroshima was a jackpot; what the first blast didn’t do, the subsequent firestorm did, and 4 square miles of the city just went away, nothing left, not even steel, much less teeth and bones.
The Nagasaki bomb was bigger, but the targeting wasn’t as good, and the city had the good fortune of having a lot of hills, which shielded some from the blast, the heat, the radiation. Moreover, the hills altered the wind field, and the resulting fires are only classed as a conflagration. Still, 40,000 people died quick, and maybe four times that number died slow, from injuries, from radiation, from the long term illnesses that go with radiation, from trauma, and grief.
In 1944, the most powerful bomb used in warfare was the British Grand Slam on the order of 10 tons of TNT, although the U.S. developed (but never used) one that was twice as big. In 1945, of course, nuclear weapons increased bomb yields by three orders of magnitude.
It’s hard to develop a sense of scale once you start dealing in factors of a thousand. People think “nuke” and think “Hiroshima and Nagasaki.” But those bombs were measured in kilotons.
Thermonuclear weapons are measured in megatons, another factor of a thousand, so we got a factor of one million increase in about half a decade. Go look for pictures of atmospheric bomb tests. See that one near the mountain? You can see the billows in the clouds and dust that it shakes up the near field.
That’s a bomb that’s in the kiloton range. There have been industrial accidents that can be measured in kilotons, like the Pacific Engineering Company plant in Henderson, Nevada, where over a thousand tons of ammonium perchlorate blew up. That was a kiloton explosion.
Now go find some photos of the Pacific island H-Bomb tests. Google on “Castle Bravo” for example, the biggest miscalculation in the history of nuclear weapons. It was supposed to produce 6 megatons; instead they got 15. “Castle Romeo” was part of the same mistake. They expected 4, but got 11.
See those shapes in the sky above the mushroom cloud? That’s the stratosphere.
The thermal radiation effects of nuclear devices loom larger as the energy release increases. In Hiroshima, the firestorm was likely caused by the blast itself, in the same way that an earthquake causes fires, by turning building into kindling, by releasing natural gas, by rupturing fuel tanks. The heat from the bomb itself probably lit only a few of the fires.
But megaton blasts, perhaps over grasslands, forests, farms? The experiment has yet to be preformed. And calculations, simulations, and estimates are so very, very unsatisfying, aren’t they?
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Responses to “Firestorms”
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on 23 Oct 2007 at 9:15 am 1. Oaktown Girl said …
I know this is completely related to global warming. I heard on the radio (KPFA) this morning that the severity and frequency of these annual wildfires happening in the west is something that began in the 80’s – coinciding with climate change. And I thought to myself, “Hey, that’s right!” While this has been going on pretty much yearly since the 80’s, it most certainly was not a yearly thing in the 70’s when I was a kid. It’s just been happening for so long now, I had forgotten about that.
This year in Southern CA had been hotter and dryer than it’s been in 90 years.
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on 23 Oct 2007 at 10:42 am 2. Seattle said …
So the nice lady sweeping the pavement outside the gas kiosk this morning as I gassed up the car was commenting enthusiastically on how nice and warm it was (50 degrees at a little after 7am). My response: “If this keeps up, we’ll be the California of the west coast.” Which means I just might be retiring to Alaska… LOL
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on 23 Oct 2007 at 11:08 am 3. Oaktown Girl said …
Just got a call this morning from on of our clients who was supposed to be up here for an event happening tomorrow. Turns out he lives in San Diego and has been evacuated from his home. He was calling to see if he could get his ticket refunded. Being the great actress that I am, I told him in my most serious and monotone bureaucratic voice, “I’m sorry, sir. You would be covered in the event of an earthquake or flood, but, that ticket does not come with fire refund coverage”.
There was a slight pause before he burst out laughing, so at least I got him to smile on an otherwise very grim day.
Which means I just might be retiring to Alaska… LOL
Funny you should say that, Seattle. I was just wondering this morning where on Earth one could attempt to flee, and I could not think of anyplace that would be an escape from the ravages of global warming. Moving north is not going to be so great with prices rocketing out of the universe and overcrowding, plus pests (insects, flying bugs, etc) will probably be out of control as well. Maybe crazy-ass Dick Cheney will bring about the Glorious Giant Nuclear Fireball before it gets too bad.
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on 23 Oct 2007 at 1:58 pm 4. spyder said …
Firestorms generate their own weather, their own winds, and can create small tornadoes, “dust devils” made out of flaming gases that light everything they touch.
I keep a picture (another one of those moments i think i should have a scanner) of just such a flaming tornado on my refrigerator. I took the picture, after i packed my truck (for the second time in two years) and prepared to leave. There is a three-story house in the image, which appears to be 1/10th the size of the face of this monster. My friend, who lived up the hill above me, stayed with his house (mostly stone w/ a metal roof) using his own gravity-feed water system to keep the surrounding landscape wet, until he took cover in his subterranean basement. I took off down the road as fast as i could somewhat safely drive. Fortunately (and one more time) my ranch house and out-buildings got bombed with borate, and i only lost some trees and most of my wooden fences. My friend’s house was the only one of 27 that survived in that section of the upper canyon. Most of us (six ranches, mostly on the Washoe Reservation) were saved.Twenty-seven days later there came the usual mid-Summer monsoonal thunderstorms, and a gnarly flashflood came through my property taking out my chickens, most of my remaining fences, and completely filling my 12′deep stockpond with humus/topsoil. I suspect that the winter rainy season in SoCal will continue the pattern of massive destruction across enormous swaths of landscape.
I have lived through many similar disasters during my relatively long lifetime: fires, earthquakes, floods, tornadoes; now i hope to live out my days safely ensconced in this historic district downtown in a nice, medium-sized city. The proximity to the USAF base might contain some as yet undetermined GNF threat in some nasty 3rd world war future, but for now i no longer need to live in forests, on coastline hills, up on mountain ridges, or down in canyons, no matter how damn beautiful they are.
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on 23 Oct 2007 at 2:03 pm 5. spyder said …
The following is from the transcript of the CBS 60 minutes segment on superfires of the Western US, which aired on Sunday.
The fire season in the last 15 years or so has increased more than two months over the whole Western U.S. So actually 78 days of average longer fire season in the last 15 years compared to the previous 15 or 20 years,” Swetnam says.
Swetnam says that climate change — global warming — has increased temperatures in the West about one degree and that has caused four times more fires. Swetnam and his colleagues published those findings in the journal “Science,” and the world’s leading researchers on climate change have endorsed their conclusions.
But what was news to the scientists is something Tom Boatner has noticed for about ten years now. “This kind of low brush would normally be really moist and actually be a fairly good barrier to fire. But as I look at this I just see wilted leaves everywhere. There’s no moisture left in them. They’re dead,” he points out.
…“You know, there are a lot of people who don’t believe in climate change,” Pelley remarks.
“You won’t find them on the fire line in the American West anymore,” Tom Boatner says. “‘Cause we’ve had climate change beat into us over the last ten or fifteen years. We know what we’re seeing, and we’re dealing with a period of climate, in terms of temperature and humidity and drought that’s different than anything people have seen in our lifetimes.”
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on 23 Oct 2007 at 2:41 pm 6. Oaktown Girl said …
Thanks for the great quotes, spyder.
East San Diego county residents have been protesting the planned 200 acre Blackwater facility in their county. This piece from Common Dreams is from April 13, but there was also another protest just this Oct. 8th.
Blackwater USA…is seeking to build a 220-acre training camp on an 800-acre parcel that now is dedicated to egg farming and cattle ranching.(snip)
Plans include firing ranges, a helicopter pad, a mock “combat town,” a track for high-speed driving classes, classrooms, an armory, a bunkhouse and some administrative buildings.
San Diego protests Blackwater. Now San Diego is in flames, and some of the fires reportedly could be arson. Strange coincidence?
This and more photos from the LA Times. -
on 23 Oct 2007 at 4:27 pm 7. James Killus said …
This is from a comment by Patricia Shannon on a thread called “Preaching to the Converted” over on Mark Thoma’s Economist’s View:
Just today, a co-worker gave his opinion that the Sierra Club is The Cause of the wildfires that are ravaging California, because they are The Cause of the buildup of fuel, that professional forstors only went along with putting out all fires because of pressure from the Sierra Club. When I said I would check the Sierra Club web site and see their current policy, he said not to do it for him, he already knows the facts, he saw some documentary. When I asked if he saw it on Fox news, he didn’t know, implying he does get at least some of his info from Fox news. When he said he wasn’t interested in the facts, I should have shut my mouth, but I ended up telling him he was crazy, not helpful, I know.
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on 23 Oct 2007 at 4:50 pm 8. Oaktown Girl said …
There’s a huge misconception out there on the right about what sort of forest clearing constitutes fire prevention. It’s underbrush that needs to be cleared, not healthy trees!! In fact, healthy trees often survive major fires just fine, and act as retardants against further spreading of the fire. This whole right wing nonsense about the “tree hugers” being the problem (because they don’t want perfectly healthy trees cut down) is beyond maddening.
Back to Blackwater - whether they have a tie to the fires in San Diego or not, this is EXACTLY the kind of situation that fascist outfits like them pounce upon. Projects and policies that can’t get public approval normally are easily rammed through in times of crisis: post-Katrina New Orleans, post 9/11 US Constitution, etc. Naomi Klein does an outstanding job spelling it out in her new book The Shock Doctrine: The Rise of Disaster Capitalism. They take advantage of people when they are most powerless and/or in shock, and then impose whatever they want. Blackwater’s never been more poised to have their San Diego super facility.
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on 23 Oct 2007 at 6:31 pm 9. christian h. said …
These fires are really awful, and as Oaktown Girl says, anyone who’s read The Shock Doctrine has to expect what’s coming (not to Malibu - they’re just going to rebuild whatever is destroyed - but to poorer communities, for sure.)
I have several colleagues living down there - as far as I know, none have been evacuated yet, but this may change.
What the hell was P. Shannon’s coworker even talking about? These aren’t forest fires in the first place, but brush fires, as far as I understand. And the reason fires all over the West are put out early is, at least in part, sprawl.
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on 23 Oct 2007 at 8:02 pm 10. Kiera said …
That coworker is wearing blinders, along with all the other brainwashed sheep that this country calls registered (mostly republican) voters.
Yes, this started as brushfires, at least most of them did. It’s jumping 10 lane wide freeways made of solid asphalt and concrete, for pity’s sake. No amount of logging could have stopped this thing. More things to break the wind (trees, perhaps?) might have helped, but even that is questionable.
OTG and I have friends down there who are only three freeway exits away (at last report) from the evacuations. They’re packed and ready to move the valuables (sentimental and otherwise) if they get the call. Meanwhile, as they both work in San Diego hospitals, they’re staying put as long as officially allowed so as not to disrupt patient care. Otherwise, they’d take their baby daughter and head north.
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on 23 Oct 2007 at 8:12 pm 11. Oaktown Girl said …
Here’s a video showing people for and against the Blackwater Super Compound in San Diego. Warning: the people in favor of it show a jaw-dropping level of ignorance on a number of issues, not the least of which is the consequences of handing over authority domestically to a privatized military outfit with accountability to neither civilian nor military law. Worth watching the whole thing.
Information on how you can help is here. Whether you live in the San Diego area or not, this affects all of us.
There’s no video that I can find, but tonight Keith Olbermann interviewed someone who talked about how global warming is a key factor in these Southern CA fires, and how BushCo is trying to distance themselves from that fact. George Carlin was also on tonight, and there is video of that (of course) here. (Starts out kind of mundane, but George brings the hammer out toward the end. Mandatory commercial first).
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on 24 Oct 2007 at 9:54 am 12. spyder said …
In response to Oaktown Girl and christian’s suggestions regarding the aftermath probabilities, Bill Scher wrote yesterday about Louisiana’s gubernatorial election of this weekend:
All According to Plan
Submitted by Bill Scher on October 22, 2007 - 2:03pm.
Conservative movement favorite Bobby Jindal cruised to victory in Saturday’s Louisiana gubernatorial election, winning 53% of the vote in a multi-person race, far ahead of the pack and avoiding a runoff election against a single opponent. But Jindal got roughly the same amount of votes as four years ago, when he won only 48% of the vote and lost the governor’s race.
There were multiple factors at play. The Democratic leadership in the state suffered their share of the blame for Katrina and its aftermath, potentially strong opponents did not join the election, and the race was never close. But we cannot ignore the new demographics of Louisiana, as conservative policies made it extremely difficult for African-American voters to come home.
The Politico’s report on Jindal’s victory notes:
Jindal’s victory heralds the GOP’s further ascendancy in Louisiana, particularly in the face of sweeping demographic changes after Hurricanes Katrina and Rita.
Massive flooding sent many black Louisianans, who often vote Democratic, fleeing from the state to Texas, Utah and elsewhere. While the full political impact of the population shifts from the 2005 storms are still being revealed, it’s clear that Republicans are stronger than before.Just before the election, conservative columnist Robert Novak observed (via Political Wire):
One underlying reason for bright Republican prospects in Louisiana’s statewide elections Oct. 20 is the departure from the state of an estimated 173,000 African Americans, dependable Democratic voters, after Hurricane Katrina.
New Orleans is still 58 percent African American, according to a Brookings Institution survey, compared with 67 percent before the storm. But migration of blacks, mainly to Houston and Atlanta, lost the recent Democratic hard core in Louisiana.http://commonsense.ourfuture.org/all_according_plan?tx=3
CA GOP couldn’t get the illegal aliens out, they couldn’t get the election law changed to allow divided electoral votes, they couldn’t redistrict to insure their control of the state legislature: so just burn it down and start over????
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on 24 Oct 2007 at 12:39 pm 13. spyder said …
Bush Budget Request Raises Fears Of Iran Strike, Increases Funding For ‘Massive’ ‘Bunker Buster’
In light of the administration’s increasingly threatening rhetoric on Iran, CQ reports that members of Congress are worried by Bush’s recent budget proposal. In particular, they cite his request to equip B-2 “stealth” bombers with a new 30,000-pound bunker buster as a “sign of plans for an attack on Iran“:
Buried in the $196.4 billion supplemental war spending proposal that Bush submitted to Congress on Oct. 22 is a request for $88 million to modify B-2 bombers so they can drop a Massive Ordnance Penetrator, or MOP, a conventional bomb still in development that is the most powerful weapon designed to destroy targets deep underground.
A White House summary accompanying the supplemental spending proposal said the request for money to modify B-2s to carry the bombs came in response to “an urgent operational need from theater commanders.” […]
Previous statements by the Defense Department and the program’s contractors, along with interviews with military experts, suggest the weapon is meant for the kind of hardened targets found chiefly in Iran.
The B-2 bomber and MOPs are reportedly choice weapons for strikes against Iranian nuclear facilities. In January, the BBC reported that the administration had drawn up plans for “long range B2 stealth bombers” to “drop ‘bunker-busting‘ bombs” in an effort to penetrate, for example, the Natanz enrichment facility in Iran.
The MOP has been in development for several years. After its completion, a U.S. military officer proudly described the destructive power of the bunker buster, specifically saying it could be used against Iran:
The U.S. has a 14-ton super bomb more destructive than the vacuum bomb just tested by Russia, a U.S. general said Wednesday.
The statement was made by retired Lt. General McInerney, chairman of the Iran Policy Committee, and former Assistant Vice Chief of Staff of the Air Force.
McInerney said the U.S. has “a new massive ordnance penetrator that’s 30,000 pounds, that really penetrates … Ahmadinejad has nothing in Iran that we can’t penetrate.”
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on 24 Oct 2007 at 1:15 pm 14. Oaktown Girl said …
spyder Dahling…don’t forget to credit that blockquote!
By the way, California, like all state facing huge disasters (tornadoes, fires, etc) is really feeling the pinch of their National Guard people and equipment being in Iraq. I think I heard on the radio this morning CA is down 50% in National Guard equipment that could otherwise be used to help fight these fires. And remember, once that equipment is shipped to Iraq, it never comes back (unlike the Nation Guard personnel who, if they are very lucky, do come back).
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on 24 Oct 2007 at 9:01 pm 15. spyder said …
Oh great Minister of Justice, i humbly beseech you to accept my apology for the missing link (no not the simian relations). Here ’tis.
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on 24 Oct 2007 at 9:23 pm 16. JP Stormcrow said …
Bush Budget Request Raises Fears Of Iran Strike
Flipping through the channels tonight, avoiding seeing more of the Boston
BombersRed Sox, came across Condi testifying before congress on C-Span. Could not even understand what the hell she was talking about - it was all ….IRAN….. IRAN… misgotten gains…IRAN … kill soldiers … IRAN.It really is fucking happening again. The Iran preparation is everywhere and nowhere. The magnitude of the lies and the media wavering between indifference and complicity is just breathtaking and disheartening.
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on 24 Oct 2007 at 9:39 pm 17. JP Stormcrow said …
My first real visit to LA was to see my sister in school over Thanksgiving. I took a sightseeing drive there from Houston. The night before I got there I woke up down in the Grand Canyon, hiked up to the rim trying to ignore the fact that I did not have my car keys (I had left them in the lock - a ranger had found them and kindly left a note). When I came down Cajon Pass that evening there were fires on both sides of the road (I-15 closed shortly thereafter.) It was literally a descent into hell - and my whole stay felt that way compared to the prior week ambling through New Mexico and Arizona. (There were also fires out past Malibu - Decker Canyon I think - this would have been late ’70s early 80s.)
Although I did stop at the great Valley of Fires in New Mexico (just a short distance from ‘Trinity Site’ in White Sands) - thereby completing a trifecta of conflagration ancient to current.
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on 25 Oct 2007 at 12:07 am 18. James Killus said …
Whoa, just saw a “firestorm tornado” on the TV.
I know it’s a disaster, but it was awfully pretty…
