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Two days in an underwater cave running out of oxygen

bbc.com

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Re: Two days in an underwater cave running out of oxygen

#31

Post by titanomachy »

biggc wrote: post #19

> He realised the water at the surface of the lake was drinkable Can someone explain this phenomena? How can the water in a sea-cave become potable?

I'm not familiar with Mallorca's hydrogeology, but I've done some cenote (cavern) diving in Mexico's Yucatan peninsula. The caves are inland, but sea water infiltrates through the porous and channel-filled rock. The water nearer the surface is rainwater.

The narrow region where freshwater and seawater intermingle is called the halocline, it creates a cool optical distortion which reminds me of the "oil paint" filter in photoshop.

Re: Two days in an underwater cave running out of oxygen

#32

Post by logfromblammo »

biggc wrote: post #19

> He realised the water at the surface of the lake was drinkable Can someone explain this phenomena? How can the water in a sea-cave become potable?

Water can stratify if the layers have different temperature, salinity, or change in density from other causes.

https://en.wikipedia.org/wiki/Halocline

If there is no convection or wave-action to mix the saltwater with the fresh, they can coexist in the same vessel, with very slow diffusion of salt into the fresh layer. If the fresh layer is refreshed by rainfall or fresh outflows of groundwater, the top may always be drinkable, even as the bottom is not.

Re: Two days in an underwater cave running out of oxygen

#33

Post by j9461701 »

I might be speaking out of line, but taking on these kinds of risks with young children at home seems kind of selfish. The fact that he went back into the same cave that nearly killed him only a month later...almost as if to say:

"I would rather my kids grow up without a Dad than live without my adrenaline fix"

I am neither a father or a cave diver though, so I might be missing a piece of the puzzle. Would either groups of people care to comment?

Re: Two days in an underwater cave running out of oxygen

#34

Post by awalton »

omnimus wrote: post #28
narrator wrote: post #17

Earlier quoted context omitted.

Or you can watch Youtube vids like this : https://www.youtube.com/watch?v=WtlwoX1YEmg This has got to be the scariest video on Youtube in which no harm comes to anyone.

Why would anyone do that?!

Adrenaline is a powerful endogenous drug...

Re: Two days in an underwater cave running out of oxygen

#35

Post by seanc »

j9461701 wrote: post #33

I might be speaking out of line, but taking on these kinds of risks with young children at home seems kind of selfish. The fact that he went back into the same cave that nearly killed him only a month later...almost as if to say: "I would rather my kids grow up without a Dad than live without my adrenaline fix" I am neither a father or a cave diver though, so I might be missing a piece of the puzzle. Would either gro…

I am a father and I agree 100%

IMO maaaaybe you could be married with no kids and do this ethically. But with kids? You're rolling the dice on a very important promise.

I do struggle with what that line of thinking means for soldiers though.

Re: Two days in an underwater cave running out of oxygen

#36

Post by sametmax »

j9461701 wrote: post #33

I might be speaking out of line, but taking on these kinds of risks with young children at home seems kind of selfish. The fact that he went back into the same cave that nearly killed him only a month later...almost as if to say: "I would rather my kids grow up without a Dad than live without my adrenaline fix" I am neither a father or a cave diver though, so I might be missing a piece of the puzzle. Would either gro…

You can decide that having children doesn't mean you have to sacrifice everything for them.

If you greatest joy in life is this, you may choose to take the risk. Children are not an all or nothing proposal.

Re: Two days in an underwater cave running out of oxygen

#37

Post by mfoy_ »

dotancohen wrote: post #30
narrator wrote: post #17

Earlier quoted context omitted.

Or you can watch Youtube vids like this : https://www.youtube.com/watch?v=WtlwoX1YEmg This has got to be the scariest video on Youtube in which no harm comes to anyone.

> This has got to be the scariest video on Youtube in which no harm comes to anyone. Off topic, but here is a viable contender: https://www.youtube.com/watch?v=hFMHjDqHL_Y There are videos of higher towers, but I believe that this video is the most thoroughly annotated one.

Wow... they must really have to time these service trips with the weather... You'd be so exposed...

Also surprising is the apparent lack of safety... the carabiners / clips just loosely hang around the occasional rung and are often completely unattached... I wouldn't trust that if he fell the clip would hold him.

Re: Two days in an underwater cave running out of oxygen

#39

Post by agumonkey »

j9461701 wrote: post #33

I might be speaking out of line, but taking on these kinds of risks with young children at home seems kind of selfish. The fact that he went back into the same cave that nearly killed him only a month later...almost as if to say: "I would rather my kids grow up without a Dad than live without my adrenaline fix" I am neither a father or a cave diver though, so I might be missing a piece of the puzzle. Would either gro…

Some people just do what they need to, I'm saying this from Jeb Corlis, famous wingsuit diver, who said he just cannot avoid jumping even though it's more than risky, deadly AND that he crashed once (one of the luckiest comeback I ever got to see). His family isn't happy, but he cannot live otherwise so it's either depression or adrenaline.

Re: Two days in an underwater cave running out of oxygen

#40

Post by coleifer »

j9461701 wrote: post #33

I might be speaking out of line, but taking on these kinds of risks with young children at home seems kind of selfish. The fact that he went back into the same cave that nearly killed him only a month later...almost as if to say: "I would rather my kids grow up without a Dad than live without my adrenaline fix" I am neither a father or a cave diver though, so I might be missing a piece of the puzzle. Would either gro…

I race motorcycles and also ride on the street most days, so this is a familiar topic of discussion with my wife, especially considering that we have a two-year-old son. What I can say on the subject is that there's a big difference between taking every precaution to minimize risk and being careless or reckless. What stood out to me when reading this article was "why the fuck would you use a guideline that could break so easily?" and also "why wouldn't you give yourself more margin with regards to your air supply?" That's just stupid, in my opinion.
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