5 ms·

Did the the ocean influence the ease of expansion of the explosion? Or hinder it? We are comparing an underwater explosion to one on land, and I'm wondering if

Did the the ocean influence the ease of expansion of the explosion? Or hinder it? We are comparing an underwater explosion to one on land, and I'm wondering if it's directly comparable.

mytailorisrich 5y ago
From what I've read it seems that the ocean exacerbated the explosion: the hot magma caused water to vaporize and created a steam explosion. I've read about a 70x volume expansion and that the top altitude of the plume was steam. On the other hand, the ocean might have captured some of the ash (?)
- Retric 5y ago
  It should have also significantly reduced the temperature of the resulting ash cloud which reduced the quantity of particulate matter in the upper atmosphere. Which presumably reduces how much short term global cooling you get from the eruption.
- CoastalCoder 5y ago
  I'm curious if this would cause a noticeable change in the pH of those waters, and if that could be a good basis for estimating how much ash was captured.
  - zo1 5y ago
    I wonder how many tonnes of fish got destroyed, cooked, or otherwise thrown many kilometers into the air.
    - datavirtue 5y ago
      That sounds delicious
    - OneLeggedCat 5y ago
      I was thinking that too about whales and birds. Some species are found only on/around an island or two, like many of the Galapagos species.
      - GekkePrutser 5y ago
        At least for once humans were not to blame :)
- neom 5y ago
  I wonder if all that steam condensing would also help contain the ash. If it was that much steam I guess as it cooled it "rained"?
- wrycoder 5y ago
  This reminds me of Jules Verne’s Mysterious Island, which was the first adult book I ever read. It featured a catastrophic underwater volcanic explosion. Great book, it’s a Robinson Crusoe-style sequel to Twenty Thousand Leagues Under the Sea. Interestingly, Verne wrote the book nine years before the Krakatoa explosion. He must have been thinking of Tambora, though I’m not sure that eruption was well recognized at the time.
- dredmorbius 5y ago
  I ran a quick bit of napkin maths a few days back here on HN. Based on 6 MT energy release, a maximum of 11 million tonnes (or 11 million m^3) of water could have been vapourised. Liquid-to-gas expansion is on the order of 1,000 times, not 70x. This would be 11 km^3 of expansion. If the erruption yield was higher, and I've seen values of up to 50 MT suggested, the amounts would be roughly 9x greater: 100 million tonnes and 100 km^3 of steam. All of this is very rough and is strictly based on the quantity of energy and the heat of vapourisation of water. Actual quantity of water/steam is likely lower. There's no geology involved in the estimate, just physics. See: https://news.ycombinator.com/item?id=30019044 https://news.ycombinator.com/item?id=30019044

Did the the ocean influence the ease of expansion of the explosion? Or hinder it? We are comparing an underwater explosion to one on land, and I'm wondering if it's directly comparable.

mytailorisrich 5y ago

From what I've read it seems that the ocean exacerbated the explosion: the hot magma caused water to vaporize and created a steam explosion. I've read about a 70x volume expansion and that the top altitude of the plume was steam. On the other hand, the ocean might have captured some of the ash (?)

Retric 5y ago
It should have also significantly reduced the temperature of the resulting ash cloud which reduced the quantity of particulate matter in the upper atmosphere. Which presumably reduces how much short term global cooling you get from the eruption.
CoastalCoder 5y ago
I'm curious if this would cause a noticeable change in the pH of those waters, and if that could be a good basis for estimating how much ash was captured.
- zo1 5y ago
  I wonder how many tonnes of fish got destroyed, cooked, or otherwise thrown many kilometers into the air.
  - datavirtue 5y ago
    That sounds delicious
  - OneLeggedCat 5y ago
    I was thinking that too about whales and birds. Some species are found only on/around an island or two, like many of the Galapagos species.
    - GekkePrutser 5y ago
      At least for once humans were not to blame :)
neom 5y ago
I wonder if all that steam condensing would also help contain the ash. If it was that much steam I guess as it cooled it "rained"?
wrycoder 5y ago
This reminds me of Jules Verne’s Mysterious Island, which was the first adult book I ever read. It featured a catastrophic underwater volcanic explosion. Great book, it’s a Robinson Crusoe-style sequel to Twenty Thousand Leagues Under the Sea. Interestingly, Verne wrote the book nine years before the Krakatoa explosion. He must have been thinking of Tambora, though I’m not sure that eruption was well recognized at the time.
dredmorbius 5y ago
I ran a quick bit of napkin maths a few days back here on HN. Based on 6 MT energy release, a maximum of 11 million tonnes (or 11 million m^3) of water could have been vapourised. Liquid-to-gas expansion is on the order of 1,000 times, not 70x. This would be 11 km^3 of expansion. If the erruption yield was higher, and I've seen values of up to 50 MT suggested, the amounts would be roughly 9x greater: 100 million tonnes and 100 km^3 of steam. All of this is very rough and is strictly based on the quantity of energy and the heat of vapourisation of water. Actual quantity of water/steam is likely lower. There's no geology involved in the estimate, just physics. See: https://news.ycombinator.com/item?id=30019044 https://news.ycombinator.com/item?id=30019044