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LA wildfires force thousands to evacuate, NASA JPL closed

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Re: LA wildfires force thousands to evacuate, NASA JPL closed

#61

Post by trhway »

JumpCrisscross wrote: post #47
trhway wrote: post #42

Earlier quoted context omitted.

there is no issue in detecting. You sweep the area. The IR sources like a tank - pops up like Xmas tree even on relatively cheap IR from 10km (there is a lot of footage from Ukraine war for example). A house fire would easily pop-up even from tens of km. A acre size fire - it would pop-up even on coarse grain IR from space.

> house fire would easily pop-up even from tens of km. A acre size fire - it would pop-up even on coarse grain IR from space Both of these produce lots of smoke. Neither can be doused by drones.

>Both of these produce lots of smoke.

i suggest you view a bunch of real IR footage.

> Neither can be doused by drones.

I'm pretty sure 20 tons of water would douse a house fire. It would take 10 flights of an F8F Bearcat sized drone. Though the F8F is an overkill built for speed. One can carry 1-2 ton with much simpler plane today for that purpose.

An acre size fire - an acre-inch of water is 100 ton. So 10 drones 10 flights at 1 ton/drone.

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#62

Post by bsder »

crazygringo wrote: post #36
trhway wrote: post #21

One can imagine an IR monitoring (satellite or high flying drones like Reaper, one drone can see an IR source like a tank from 100km, so it would take just a few drones to monitor the the whole state for fires) with [almost] automated immediate dispatching of the fleet of drones (not small quadcopters, more like WWII size bombers) once the fire is detected. Would be much cheaper than having multi-billion dollar fires…

You're currently being downvoted, but I'm genuinely curious -- is continuous IR monitoring from the sky an effective way to detect wildfires earlier? Or are small fires indistinguishable from a million other hot objects, until the point where they get large enough to detect reliably, it's already obvious to everyone on the ground from the smoke?

It could be for fires on normal weather days.

The problem is that with these winds and humidity small fires become huge fires before anybody can react. Once they are huge fires, detection isn't the problem.

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#63

Post by JumpCrisscross »

trhway wrote: post #61
JumpCrisscross wrote: post #47

Earlier quoted context omitted.

> house fire would easily pop-up even from tens of km. A acre size fire - it would pop-up even on coarse grain IR from space Both of these produce lots of smoke. Neither can be doused by drones.

>Both of these produce lots of smoke. i suggest you view a bunch of real IR footage. > Neither can be doused by drones. I'm pretty sure 20 tons of water would douse a house fire. It would take 10 flights of an F8F Bearcat sized drone. Though the F8F is an overkill built for speed. One can carry 1-2 ton with much simpler plane today for that purpose. An acre size fire - an acre-inch of water is 100 ton. So 10 drones 1…

> suggest you view a bunch of real IR footage

For what? I’m familiar with very sensitive IR systems. I’m struggling to see the advantage of having them on drones versus satellites, particularly if the threshold is an entire house is on fire.

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#64

Post by Jtsummers »

JumpCrisscross wrote: post #57
Jtsummers wrote: post #50

Earlier quoted context omitted.

They're talking about both detecting and dousing. Note they mention two different kinds of drones (a few monitor drones, and then a fleet of drones to deploy and douse). The monitor drones could be practical, we've demonstrated that loitering sensor drones work well in other domains. Depending on the sensor payload (what it's looking for) and how the data is stored and used, it wouldn't really entail a huge privacy p…

> it wouldn't really entail a huge privacy problem unless you show up on IR sensors as well as a fire If you’re hoping to do better than sighting a smoke column, you will absolutely have to be. We’re not at a loss of detecting entire houses burning.

To violate your privacy an IR sensor would have to be able to pick out people (98 degrees Fahrenheit, approx.) and put them on a map. Versus a sensor tuned to an actual fire which is substantially hotter and larger.

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#65

Post by tanseydavid »

JumpCrisscross wrote: post #47
trhway wrote: post #42

Earlier quoted context omitted.

there is no issue in detecting. You sweep the area. The IR sources like a tank - pops up like Xmas tree even on relatively cheap IR from 10km (there is a lot of footage from Ukraine war for example). A house fire would easily pop-up even from tens of km. A acre size fire - it would pop-up even on coarse grain IR from space.

> house fire would easily pop-up even from tens of km. A acre size fire - it would pop-up even on coarse grain IR from space Both of these produce lots of smoke. Neither can be doused by drones.

>> Neither can be doused by drones.

Identification only by drone. Then the dousing is done by conventional means, but dispatched locally.

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#66

Post by defrost »

segasaturn wrote: post #51

Los Angeles Fire Department funding was cut by over $23M only a few months ago. The fires are currently being fought by a skeleton crew of remaining fire fighters and volunteers. Can't say if that funding would have prevented it, but cutting it definitely has not helped. Source: https://www.politico.com/news/2025/01/08/los-angeles-fires-m... Edit: Changing a word, "gutted" -> "cut"

Someone tweeted $23 million .. your linked article (thank you for source) follows that with:

  City budget documents show the department’s more than $800 million budget decreased by around $17 million compared to the previous budget cycle.
Which makes the cuts less than %2.12

"Gutted" as a descripter seems extreme and the details that matter are whether these reductions simply trimmed fat, or denied something essential that would have made all the difference here.

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#67

Post by sneak »

segasaturn wrote: post #51

Los Angeles Fire Department funding was cut by over $23M only a few months ago. The fires are currently being fought by a skeleton crew of remaining fire fighters and volunteers. Can't say if that funding would have prevented it, but cutting it definitely has not helped. Source: https://www.politico.com/news/2025/01/08/los-angeles-fires-m... Edit: Changing a word, "gutted" -> "cut"

For reference the LAPD budget is $175 million per month.

The fire budget was cut by $17.6 million for the year, the 23M cut was proposed. The police budget was increased by $126M for the year.

For context, the LAFD annual budget is $820M and the LAPD annual budget is $2140M.

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#68

Post by earnestinger »

bragr wrote: post #39
sapphicsnail wrote: post #16

I was in Pacific Palisades when the fire started yesterday. I've never seen one spread so fast. It went from there being smoke way in the distance and people going about their lives normally, then 90 minutes later the fire was everywhere and people were panicking and evacuating en masse.

I have a good view of the smoke column from Brentwood. I've also never seen a fire spread that fast. Same thing, in about an hour it went from a small fire to the smoke blocking out the sun. As a testament to the speed of the winds, I've never seen a smoke column visually move so quickly. Usually at that size and distance, they feel more like static objects. Edit: I'm preparing to evacuate tonight in case the order c…

What is burning? Mostly bushes or mostly homes?

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#69

Post by JumpCrisscross »

wk_end wrote: post #60
JumpCrisscross wrote: post #14

With much of California, Texas and Florida property damage is concentrated where folks built where they shouldn’t have [1]. (At times nudged on by subsidised insurance [2].) Is that true in this case, too? (Being so close to LA, it doesn’t strike me that it could be.) If not, is my general thesis off? [1] https://www.npr.org/2023/11/06/1204923950/arizona-california... [2] https://www.sciencedirect.com/science/article…

Unfortunately there's increasingly few places where natural disasters, of one sort or another, aren't inevitable. The PNW also burns regularly now, never mind the enormous earthquake looming under us that we're terribly unprepared for. Even the northeast is starting to get buried in smoke in the summer and hit by storms like Hurricane Sandy. Tornado Alley knocks out much of the midwest. What's left of the US? Desert…

> there's increasingly few places where natural disasters, of one sort or another, aren't inevitable

Sure. That doesn’t mean you can’t mitigate damage.

Not e.g. building on the Houston flood plain is one such example [1].

[1] https://www.houstonchronicle.com/news/houston-texas/houston/...

Re: LA wildfires force thousands to evacuate, NASA JPL closed

#70

Post by maxerickson »

0xffff2 wrote: post #44
crazygringo wrote: post #36

Earlier quoted context omitted.

You're currently being downvoted, but I'm genuinely curious -- is continuous IR monitoring from the sky an effective way to detect wildfires earlier? Or are small fires indistinguishable from a million other hot objects, until the point where they get large enough to detect reliably, it's already obvious to everyone on the ground from the smoke?

Yes, it is effective. We have several NASA/NOAA satellites with IR instruments on them that are used for fire detection. These are obviously much more useful for detecting fires that start in very rural areas under moderate conditions. The current crop of fires in LA are all very close to populated areas and spread fast , so satellite mapping wasn't of any use for detection. Also, California in particular has a reall…

Seems like it would be logistically difficult to be able to drop a significant amount of water anywhere in, say, 15 minutes.

With dry conditions and high winds, that is an extremely slow response to an uncontrolled fire...

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