What Happened In Yosemite?

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skyking

Lifer
Nov 21, 2001
20,184
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CO is lighter than air and CO2 heavier. You would have to be in an inclosed space to be be CO poisoned or inclosed or at the bottom of a depression to be poisoned byCO2 seems to me. Don’t know where the bodies were found but if out in the open either gas doesn’t make sense to me. What in Yosemite would be a killing source of either that could get you while hiking.
the difference in molecular weight of CO to air is minimal and it readily mixes with air and does not disperse upward. I deal with this in my line of work. My experience with automobile fumes laden with CO is that they do tend to settle. I work in confined spaces from time to time, and I have been chased up out of a structure in the ground that has filled up with CO and set off my alarm.
it is more readily detected in autopsies, however. That is what is puzzling about this case. If they died of CO poisoning it would be found in the blood and tissues. Simple hypoxia is not easy to detect.
 
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MtnMan

Diamond Member
Jul 27, 2004
7,277
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Could it be methane gas?
Methane and CO are lighter than air, thus would disparate upward.
CO2 is heaver than air in will collect near the ground.
With the ambient heat at Yosemite, I tend to think methane would just autoignite.
Uh NO!
Spontaneous ignition temperatures for stoichiometric methane-air mixtures are around 870 K (600°C/1112°F) at atmospheric pressure and decrease to 660 K (390°C) at 1100 bar ignition pressure.

But yes, the expert weighs in with "I tend to think". Do they not teach some fucking basic science in school anymore?
 

skyking

Lifer
Nov 21, 2001
20,184
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CO does not separate out and rise though. It just mixes in and hangs around. Still, any autopsy would find evidence of CO, so I am skeptical of that.
 
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Lost_in_the_HTTP

Diamond Member
Nov 17, 2019
6,196
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^^ When I installed a standby generator, I read op on CO a bit as far as distance to vents. The gist of it was that CO is relatively the same weight as ambient air and drifts easily at any level.

But it has to be concentrated to have any effect and I can't see that in an open air setting like a hiking trail. Same with CO2.

If this was a gas, it would have to have been a concentrated cloud. I haven't seen enough to know if they were in a hollow or valley of some sort.

And there would be other animal casualties.

I'm not sure if they've tested for poisons that might have been deliberately administered.
 
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Leeea

Golden Member
Apr 3, 2020
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I have spent a small amount of time in the Yosemite.

This sort of thing seems so remote out there. More then a bit disturbing.
 

Amol S.

Golden Member
Mar 14, 2015
1,751
405
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Methane and CO are lighter than air, thus would disparate upward.
CO2 is heaver than air in will collect near the ground.

Uh NO!
Spontaneous ignition temperatures for stoichiometric methane-air mixtures are around 870 K (600°C/1112°F) at atmospheric pressure and decrease to 660 K (390°C) at 1100 bar ignition pressure.

But yes, the expert weighs in with "I tend to think". Do they not teach some fucking basic science in school anymore?
Methane comes from the ground or may also contact lava. This could raise the temprature of the methane to surface ignition point. When reaching the surface, it could ignite. Another possibility is, one of the hikers may have lit a lighter for a cig.
 
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skyking

Lifer
Nov 21, 2001
20,184
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^^ When I installed a standby generator, I read op on CO a bit as far as distance to vents. The gist of it was that CO is relatively the same weight as ambient air and drifts easily at any level.

But it has to be concentrated to have any effect and I can't see that in an open air setting like a hiking trail. Same with CO2.

If this was a gas, it would have to have been a concentrated cloud. I haven't seen enough to know if they were in a hollow or valley of some sort.

And there would be other animal casualties.

I'm not sure if they've tested for poisons that might have been deliberately administered.
150~200 PPM will kill you. That is not what I would characterize as concentrated.
https://www.cpsc.gov/Safety-Education/Safety-Education-Centers/Carbon-Monoxide-Information-Center/Carbon-Monoxide-Questions-and-Answers
 
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MtnMan

Diamond Member
Jul 27, 2004
7,277
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Methane comes from the ground or may also contact lava. This could raise the temprature of the methane to surface ignition point. When reaching the surface, it could ignite. Another possibility is, one of the hikers may have lit a lighter for a cig.
I don't recall any mention of they were "burned/charred". Got a link that says they suffered burns, or even resulting wildfires given how extremely dry it is out there?

Super heated methane when exposed to oxygen would be like a giant blowtorch coming from a vent.
 
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skyking

Lifer
Nov 21, 2001
20,184
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It is a mystery for sure. CO leaves a trace in the body, so does h2s, and methane. They will all be found.
The few gasses that don't leave an autopsy trace are CO2 and nitrogen. That is why the go bag for death with dignity is a source of nitrogen and a bag. A couple of breaths of nitrogen only and you pass out and die, and since it is 70% + of the atmosphere there is no lingering trace of it.
I daydreamed up a go bag deployment that involved a helium balloon and a nitrogen cartridge and bag.
Kick back on the lounge chair, off yourself with the nitrogen, and then a timer releases the bag from around your neck and the helium balloon carries all the evidence away.
"Hmm, he died in his sleep in his lounge chair, that lucky bastard!"
Sounds bad? Try on dementia or cancer or any other lingering death. Yeah no thanks.
 

MtnMan

Diamond Member
Jul 27, 2004
7,277
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The toxicity of CO is that it is absorbed through the lungs into red blood cells. That red blood cell is no longer capable of delivering oxygen to organs in the body. If a person takes a single deep breath of only CO, they are dead, unless their blood is replaced immediately.

With CO2, helium, argon, etc., a deep breath of that gas, may make some light-headed, dizzy, or even pass out, but the next breath containing oxygen will continue to supply O2 to the organs, and brain. Example: ever inhale a helium balloon to alter your voice, and get a bit light-headed?
 

MtnMan

Diamond Member
Jul 27, 2004
7,277
5,502
136
But it has to be concentrated to have any effect and I can't see that in an open air setting like a hiking trail. Same with CO2.
The problem with CO is that is bonds with red blood cells, virtually taking them out of the function of delivering oxygen to your cells. Low concentration will fucking kill you, because each breath takes more and more red blood cells out of the game.
And there would be other animal casualties.
Do we know they are not animal casualties, snakes, rodents, even insects, etc. in their burrows or dens?
 

balloonshark

Diamond Member
Jun 5, 2008
5,505
1,717
136
I'm going to guess they happened upon two talking bears and one of those bears stole their pic-a-nic basket. Without food and water the family ended up getting dehydrated and dying.
 

Indus

Diamond Member
May 11, 2002
7,009
2,535
136
Could also be cyanide but what in Yosemite would produce it?

I've seen people overcome by cyanide in sewers by the smell of feces and die but out in the open is really perplexing.
 

Moonbeam

Elite Member
Nov 24, 1999
68,630
4,592
126
the difference in molecular weight of CO to air is minimal and it readily mixes with air and does not disperse upward. I deal with this in my line of work. My experience with automobile fumes laden with CO is that they do tend to settle. I work in confined spaces from time to time, and I have been chased up out of a structure in the ground that has filled up with CO and set off my alarm.
it is more readily detected in autopsies, however. That is what is puzzling about this case. If they died of CO poisoning it would be found in the blood and tissues. Simple hypoxia is not easy to detect.
the difference in molecular weight of CO to air is minimal and it readily mixes with air and does not disperse upward. I deal with this in my line of work. My experience with automobile fumes laden with CO is that they do tend to settle. I work in confined spaces from time to time, and I have been chased up out of a structure in the ground that has filled up with CO and set off my alarm.
it is more readily detected in autopsies, however. That is what is puzzling about this case. If they died of CO poisoning it would be found in the blood and tissues. Simple hypoxia is not easy to detect.
The point I was wondering about is that I can think of no way that poisoning by either gas could reach toxic levels while hiking in Yosemite park. CO can kill you in a tent, however, more so at altitude.@
 

[DHT]Osiris

Lifer
Dec 15, 2015
10,272
6,888
146
The point I was wondering about is that I can think of no way that poisoning by either gas could reach toxic levels while hiking in Yosemite park. CO can kill you in a tent, however, more so at altitude.@
Presuming the dog was hanging out with them in the tent.

My bet's on a new strain of brain-eating amoeba. Gaia fighting back.
 

Torn Mind

Diamond Member
Nov 25, 2012
8,445
1,533
126
Much gnashing of teeth has now occurred amongst bureaucrats as the federal government loses tourist money due to bad press.
 

Uhtrinity

Platinum Member
Dec 21, 2003
2,223
137
106
I love it when people say CO2 is non harmful. Yea, try breathing pure Argon. It's noble, doesn't react to hardly anything, it's not toxic. If you crowd out oxygen, it just doesn't matter. My years in the shipyard, probably in my 39 years, there were several suffocation deaths due to argon in tanks.
Back in the late 90's I used to play paintball. One time I left a C02 tank in my truck not thinking much of it. On a hot summer day I got in the cab and closed the door. Before I could start the truck I realized I couldn't breath, quickly opened the door and got out. The burst disk in the tank had burst releasing the CO2 into the cab. Luckily I got out before passing out.
 

Zorba

Lifer
Oct 22, 1999
11,613
6,060
136
There's the algae thing, but wouldn't that mean they all had to consume water from the same source at more or less the same time? Or can algae put out a gas?
I know blue green algae can put off s toxic gas, but I've just heard of it making you sick.
 

Zorba

Lifer
Oct 22, 1999
11,613
6,060
136
I love it when people say CO2 is non harmful. Yea, try breathing pure Argon. It's noble, doesn't react to hardly anything, it's not toxic. If you crowd out oxygen, it just doesn't matter. My years in the shipyard, probably in my 39 years, there were several suffocation deaths due to argon in tanks.
Even liquid nitrogen can be very dangerous, because if you have a large leak it can displace the oxygen in the room. Doesn't make that 79% of every breath is already Nitrogen, without the O2 you die quickly.
 

Zorba

Lifer
Oct 22, 1999
11,613
6,060
136
Much gnashing of teeth has now occurred amongst bureaucrats as the federal government loses tourist money due to bad press.
This is ridiculous numerous people die every year in Yosemite. The week before I climbed Half Dome 5 people died on the trail, and the trail was still packed when I did it.

People have gotten sick (and I think died) from rat shit in the tent cabins, good luck reserving one less than a year out, though.
 

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