What to do with an erupting volcano?

[GPSGuided]

Just came across this video of a small eruption of Mt Ontake in Japan. According to news reports, at least 4 missing and 150 stranded. Terrible scene!

What should/can one do in such a scenario?

https://www.youtube.com/watch?v=pHvnG-w ... e=youtu.be

[Gadgetgeek]

hope the pyroclastic flow gets you before anything else. its not going to be a fun time regardless. I'd be trying to get away as fast as possible, but that is probably the thing that would get you killed just as easily.

[wayno]

cover your mouth with material you can breathe through to keep the ash out of your lungs, a scarf, cloth or buff.
pray theres not too much poisonous gases..
look up for flying boulders and try and seek shelter from them.
otherwise runlike hell, and stay out of potential lahar paths that you should have identified beforehand.
where theres a laked in the crater you have massive problems with lahars rapidly descending down the mountain. in the aftermath of the te maari crater eruptions on tongariro, a natural dam created a fresh lake that threatened the crossing track... the track had to be closed, the lake eventually gave way and obliterated the track, flooding it as covering it with boulders.
stay out of craters that are actively gassing off,, toxc gases accumulate in the craters. i know someone rendered unconscious from goning into a crater that was gassing.
the lahar from the ruapehu eruptions went through where this photo was taken,, every time , the lahar is high enough to completey cover the bridge. if you look at the far end of the bridge and above to the right you will see a person and a white sign behind them, that is how far up the lahar can rise to... and its not a gradual rise in water level... its very rapid.

[wayno]

update on the japan eruption
http://www.stuff.co.nz/world/asia/61543 ... lcano.html

[GPSGuided]

Specific in this case, I note that there's a shelter of sort in the video. Given a small scale eruption, would it have been better to go for the shelter instead of running off the mountain? The logic here is, for any significantly sized eruption, one won't be able to run fast enough and more than likely to be fatal. For a smaller one, hiding in a shelter may better protect oneself from the fumes and ashes which one can't out run. Does this line of thinking make sense?

The news reports are still conflicting. Hope all can make it out alive.

[icefest]

Update from the age:

http://www.theage.com.au/world/hikers-i ... 0n350.html

[wayno]

more info

http://space.io9.com/violent-eruption-t ... 1639813357

[wayno]

Specific in this case, I note that there's a shelter of sort in the video. Given a small scale eruption, would it have been better to go for the shelter instead of running off the mountain? The logic here is, for any significantly sized eruption, one won't be able to run fast enough and more than likely to be fatal. For a smaller one, hiding in a shelter may better protect oneself from the fumes and ashes which one can't out run. Does this line of thinking make sense?

The news reports are still conflicting. Hope all can make it out alive.

this mountain is known to lob lava bombs far and wide.... as has been noted dozens have been injured.. shelter is a definite option...
pays to understand the main threat from particular volcanoes, some are more known for poisonous gas releases, you'd want to get out of the crater if the threat of that is high, theres no reports of anyone getting overwhelmed by gases
also knowing how big the eruptions normally are on a particular volcanoe is a factor... if it normally has minor eruptions, staying in a shelter is still a good option when its known theres a threat of numerous flying rocks.
also realise very dense ash can be hot and burn, suffocate,, smother and kill people... this doesnt look like a particularly big eruption, there is a far bit of ash coating the surrounding area, but compared to how big eruptions can get the ash doesnt appear to have been at the large end of the scale.
how strong are the shelters? are they just for weather protection or are they really built like bunkers to withstand some amount of eruption debris... if boulders are being shot out of the volcanoe and the shelter isnt built to withstand them, then theres no point being in teh shelters, debris is shot up at steep angles and falls from hundreds of metres or more, you'd be better off standing in the lee of a bluff or just moving as fast as you can looking out for projectiles than staying in a weather proof only shelter. there are no shelters on nz volcanoes made to withstand rocks shot out of volcanoes...
valcanoes can vary masively in their behaviour. some may have regular small eruptions you have some chance of surviving, others may seldom erupt and if you are near it when it does your chances of doing anything to increase your chances of survival can be minimal.... in Nz people keep their eye on the central volcanic plateau, but Mt taranaki is far more dangerous, it erupts about every three hundred years in massive eruptions far bigger than those on ruapehu, if you were on it in a big eruption, you may as well just take in the spectacle as best you can because your chances of surviving it will be pretty small if you're in the wrong place... and Taupo has apocalyptic eruptions tens of thousands of years apart that have wiped out vegetation over most of the north island, smothering it with thick layers of ash and rock.

[GPSGuided]

Staying upwind and moving away from the direction of a blow may help? Thinking of Mt St Helens where one side of the mountain got blown out.

[wayno]

Staying upwind and moving away from the direction of a blow may help? Thinking of Mt St Helens where one side of the mountain got blown out.

in terms of ash cloud and gas it will. in terms of projectile rocks, no
i believe mt st helens blew out in a particular direction that wasnt necessarily to do with the wind. it has a massive crater, and blew out on one side of the mountain

http://geohazards.community.uaf.edu/201 ... st-helens/

http://petapixel.com/2013/02/26/photogr ... iles-away/

[GPSGuided]

Yes, I was referring to those two parameters separately. It blew in the direction it blew because of geological reasons.

[wayno]

roughly this time last year i was on a neighbouring mountain to the one thats just erupted... depends on the time of year but they could have had thousands on the mountain on some days in the summer holiday season. at this time of year walkers are making the best of the last of the snow free weeks before autumn snowfalls start in the coming months.

[GPSGuided]

Is Mt Ontake the one in the background with a bare top? Not very volcano like by appearance. Visited "Small Mt Fuji" Mt Azuma-kofuji some years back and that was quite a thrill to see what looked like a real volcano.

[wayno]

yes, some volvanoes have had the tops blown off them in the past or are a series of craters like the ones in tongariro park

[walkerchris77]

Set off plb, drop pack and run. Maybe take some loo paper.

[izogi]

there are no shelters on nz volcanoes made to withstand rocks shot out of volcanoes...

Case in point, anyone sheltering in Ketetahi Hut when Te Maari Crater had a small fit in 2012 would have been taking their life in their hands, possibly moreso than running, but it's hard to be sure.





Pictures courtesy of DOC's photo album and Turangi LandSAR.

There was another case in 2007, where a guy staying in Dome Shelter (near to the crater lake) lost a leg when Ruapehu decided to briefly burp and a rock crashed through the roof. His mate sprinted down the side and got help, but not a full-scale eruption. If it'd been larger they'd probably have been much less fortunate.


If there's a risk of anything like a pyroclastic flow, which is super-hot heavier-than-air so more than just gas that you could filter out, then getting to higher ground than surrounds (like a ridge or rib) before it arrives, in the hope that it'll channel below and that you're far enough away to avoid everything else that might also be lethal, is possibly the most realistic chance. (I hope I'm not spreading bad rumours as I'm not an expert here.) Staying in any shelter in its path would probably be suicide.

None of this is a situation I'd want to have to contemplate being in. The latest I've read from Japan sounds like the worst for about 30 people, although officials apparently have done everthing but confirm it. I hope I'm wrong.

[wayno]

my understanding is the poisonous gases from volcanoes are generally heavier than air, hence they can be a problem in craters,
i remember a volcanoe in africa. a massive cloud of poisonous gas erupted out of its crater and desended down the mountain and killed an entire village,,,thats an extreme example though

[wayno]

update
http://www.abc.net.au/news/2014-09-28/m ... no/5774752

[GPSGuided]

That's very sad to hear. Per photo, looked like the area had a serious dump of ash and probably gas.

[Gadgetgeek]

If its hydrogen sulfide that is coming out of the volcano, then yep, its heavier than normal air, and one whiff will put you down. Its not so much heavier than air that it couldn't get blown around on a breeze, but thats the danger. You smell the rotten eggs, then as you step into shelter, into a higher concentration, you stop smelling it. Then once its over the threshold (I think you stop smelling it at 3ppm, and 30ppm it knocks you down) lights out. But my last H2S course was a few years ago, and I'd like to leave that behind me. Not fun stuff. Uphill and upwind is your only chance against that, and against the pyroclastic flow, but that said, either way would be quick, so at least there is that. Ash cloud and sulfuric acid rain wouldn't be.

[GPSGuided]

Will the "acid rain" be seriously acidic to make contact a true hazard? Or just mild-moderately acidic, not for prolonged exposure?

Earlier Chris mentioned deployment of PLB. I'd suspect the thick plume and electrostatic conditions associated with an eruption would render a PLB next to useless, in the sense that signals won't get up.

[David M]

Apart from being stuck in pyroclastic flow or being hit by debris for which you cannot protect yourself unless you get to a shelter, I wonder if a protective safety measure would be to carry an oxygen cylinder of the type used on Everest to protect against toxic gases?

[wayno]

i dont think the acid rain is a great immediate threat. friend lives near tongariro... not sure how much it was that or the ash that fell that ruined the paint on their roof. not to mention what it will do to your car.... if it gets on your clothes and you dont clean them properly you could find your clothing falls apart.

[Gadgetgeek]

If its venting sulfur dioxide (I think thats the other nasty) then it converts to sulfuric acid on contact with water so if there is rain coming down due to the ash cloud, or say, the water in your lungs and eyes.... not fun, I'll take the H2S in that case and not feel it. There are filter cartridges designed to react it out of the air, so that would be an option as well.
As for the PLB, I think that due to the nature of the signal, they would probably be able to locate it, since even if there is some interference, its a fairly continual signal, so some will get through all the time. However, I wouldn't think anyone will be coming to get you, since it would be very dangerous to fly into that zone. A ground team may come to get you if they could, in which case, if there was a group, I would for sure be using the plb, since thats a better chance for everyone, but for just myself, thats putting a lot of people at additional risk. tough call

[izogi]

Apart from being stuck in pyroclastic flow or being hit by debris for which you cannot protect yourself unless you get to a shelter, I wonder if a protective safety measure would be to carry an oxygen cylinder of the type used on Everest to protect against toxic gases?

Maybe there could be some sense in storing that kind of stuff in shelters, where they exist. It might be presumptious to assume it would have made a difference, at least without further info. I guess it's a case of weighing risk.

Around NZ volcanoes, at least, I personally think there's still a more significant issue to worry about with large groups of densely-packed people in certain regions getting trapped unprepared for dangerous weather (notably up Taranaki and also across Tongariro), and that resources are better spent on reducing the chances of that happening. I guess the risk of an eruption's still always there and something similar could happen as what's happened in Japan.

[wayno]

more info on the type of eruptions that occur on this mountain

http://www.maniacworld.com/erupting-volcano.htm

[GPSGuided]

I wonder if the Japanese geological departments have had any indications of this eruption? I understand that they have invested heavily on research and infrastructure for early warning.

[wayno]

I wonder if the Japanese geological departments have had any indications of this eruption? I understand that they have invested heavily on research and infrastructure for early warning.

I'd doubt it, knowing Japanese health and safety they'd have shut down access to the mountain if they suspected anything... they have a system for the trains that pick up advance "p waves" that happen before earthquakes and it automatically brings the trains to a halt before the main shock hits. nothing moves again till the tracks have been checked... with the volume of high speed trains they have in operation it says something for the system that there were no rail accidents when the sendai earthquake hit. i was on a train when an earthquake happened, small one, it didnt stop but it slowed right down for a while. the only rail fatality in japan was a passenger trapped in closing doors. for a country with such an extensive rail network it tells you something about their attention to health and safety... if anyone tells you that japanese train system is well run and runs on time, they arent joking... japan never ceases to amaze me with how efficient they can be,,, I lost my train pass on a train that i got off in Kyoto. and i had to get it back from tokyo central train station, lost and found at tokyo knew exactly where it was and sent us to the platform office that had it.
no way in hell that would ever happen with the NZ rail system...

[GPSGuided]

...no way in hell that would ever happen with the NZ rail system...

Wayno, stop embarrassing the Australian rail system! Yes, some Asian countries are just obsessive with their trains. It's needed or such high population society would not function.

[icefest]

...no way in hell that would ever happen with the NZ rail system...

Wayno, stop embarrassing the Australian rail system! Yes, some Asian countries are just obsessive their their trains. It's needed or such high population society would not function.

The australian rail system might as well be non-existent.