"People who think a nuclear device is comparable to the energy released by a volcano just haven't seen a restless volcano up close. They are a whole lot bigger than they seem to be in the films. Mount St Helens is a relatively small volcano, yet it still took me nearly 6 hours to walk out of the center crater."
I can well attest to that. A year or so after the major eruption of Mount St. Helens on May 18, 1980, I had business in both Portland and Seattle and on that occasion I drove from Portland to Seattle rather than fly, as I'd normally do. (I'd been to Tektronix to whinge about ongoing problems we'd been having with a PAL 625 TV sync pulse generator—an interesting story in itself but I'll leave that for another time).
I live an ocean away—thousands of miles from Portland but I had an ulterior motive for renting a vehicle in Portland and driving to Seattle, as this time I wanted to visit and drive over the 'renewed' Tacoma Narrows bridge which replaced the infamous Galloping Gertie that failed in 1940—of which I'd learned so much about years earlier in structures and physics. Having a vehicle made that possible. Visiting Mt St Helens wasn't on my agenda—and I'd already seen it post the 1980 eruption from a commercial SFO/SEA flight although I did expect to see it in the distance to the east from the I5.
It was somewhat latish afternoon, 3:30–4:00 pm, when I arrived at my nearest point on the I5 to Mt St Helens and unexpectedly nearby there was a small airfield. Signs on the highway indicated that a company was offering joy flights to Mt St Helens, so on-the-spur-of-the-moment I decided to take the flight. Unfortunately, I was the only one wanting a flight at that time and the pilot told me that it was uneconomic to take only one person (two being the minimum) so I'd have to wait until additional sightseers turned up—and if that didn't happen soon (within 15 or so minutes) then it'd be too late in the day to fly! Anyway, I struck a deal at somewhat less than the amount for two people and we were on our way.
I don't need to describe this remarkable scene except to say it was spectacular—much more so than the somewhat limited view from the commercial jet; and anyone who's interested will already be familiar with the wonderful photos in National Geographic and elsewhere. However, one point I must comment on is that for mile after mile in this desolate lunar-mud-like landscape the remaining trunks of the flattened pine trees were all facing radially away from the exit point of the explosion like the spokes of a bicycle wheel, it was one of the strangest sights I've ever seen. There was no doubt that this was an extremely huge explosion.
After doing the standard joy flight, the pilot suggested that seeing I'd paid much more than the normal fare would I like him to take me closer to the crater. Gleefully, I agreed and we not only got closer to the crater but we actually flew around inside it — right, the crater is truly huge when one's actually inside it! When the author says it took him nearly 'six hours to walk out of the center of the crater' he not exaggerating one iota.
'Tis a damn shame photos aren't allowed on HN, otherwise I'd post some of my old slides taken from inside the crater (they're truly spectacular).
> "People who think a nuclear device is comparable to the energy released by a volcano just haven't seen a restless volcano up close. They are a whole lot bigger than they seem to be in the films. Mount St Helens is a relatively small volcano, yet it still took me nearly 6 hours to walk out of the center crater."
Maybe volcanologists who don't think a nuclear device is comparable to the energy released by a volcano just haven't seen a peeved hydrogen bomb up close.
USGS estimated the blast from Mt. St. Helens was 7 megatons and 17 megatons of other thermal energy released (I guess most of that is magma flowing out).
The early large fusion bombs are comparable to that, actually bigger. The largest one ever tested was 50 megatons and had a design capable of 100 megatons https://www.youtube.com/watch?v=YtCTzbh4mNQ.
"Mt. St. Helens was 7 megatons and 17 megatons of other thermal energy released..."
Well, at minimum, that's still between 400 and 700 times the energy released during the Hiroshima explosion. That's over two magnitudes more energy and I'm glad I wasn't anywhere near it at the time. ;-)
The Tsar Bomba (which I remember as a kid) had to be made to prove a point but as Kurchatov, Sakharov etc. seemed to realize at the time, making the 100 megaton bomb wouldn't add much to the argument (presumably other than additional cost). There was no point making a bigger bomb as the additional energy essentially would have been blown out into space thus not substantially increasing the blast area.
Anyway, that's not the point which is that even on piddling little earth nature has ways of producing huge amounts of destructive energy. As for supernovas, etc. except by way of mathematical calculations, I don't think the average human can actually contemplate or imagine energy on such a scale.
It was the point of the sentence I was responding to, which claimed that nuclear bombs were not comparable to volcanoes in terms of energy released. They are, at least volcanoes like Mt. St. Helens.
The Americans made bombs larger than St. Helens too.
I hiked up to the rim of MSH a couple decades ago, but didn't go down into it. I can attest that it's pretty big in there. And the sight of the giant blown-down trees for miles around is incredible.
I'm a long-time hiker too, and that Mt St Helens hike I'd have loved to have done.
(When a kid, my parents' home was within five minutes walking distance of a national park: https://www.nationalparks.nsw.gov.au/visit-a-park/parks/blue.... In effect, it was our backyard and in those days we could get into all sorts of trouble without helicopter parents bothering us or cramping our style, (back then it was common for us kids at the age of 10 or 11 to go roaming in those valleys without supervision). However, there were no active volcanoes, the nearest to my home being about 20 miles away and it has been dormant for millions of years:
https://www.nationalparks.nsw.gov.au/visit-a-park/parks/moun....)
When you mentioned that you were hiking at MSH several decades ago, it suddenly dawned on me that that flight of mine was 40 years ago (hell those years seem to have disappeared quickly). As I said, what I saw was nothing but destruction and desolation, but presumably by the time of your visit some 20 years later you would have seen new growth starting to take hold everywhere. Even so, from some pictures I've just seen on the web, 40 years still isn't long enough for nature to hide the event.
Yeah you're right. But I think I spoke too soon. I've been looking and I've still not found them yet (but I know that I still have them). I have over 30,000 slides in those little yellow Kodak boxes and a similar number of color and B&W negatives and to date I've only managed to scan about 1% — 2% of them!
I shouldn't be allowed to sort and cull my own photos as I'm too possessive of them and I don't trust other members of my family or friends who are in the photos to do so either (as they've been known to spirit away technically excellent photographs of themselves that don't show them in a flattering light).
Then there's the entropy problem: in say a bracket of photos the ones with the best focus, composure etc. don't necessarily have the best exposure, color balance etc. so I can't decide what to discard and so keep putting off the hard cull (at least 3/4 of them need to go).
However, in the interim, I found this site (and I'm sure there are many more with a bit of looking): https://rarehistoricalphotos.com/eruption-mount-st-helens-19.... This site has some excellent photos and many of the aerial shots are very similar to mine. (If anyone else has found similar sites then post links here.)
I draw your attention to the photos with descriptions that begin the following commentary:
• 'Aerial view of timber blowdown, destroyed by the May 18 eruption...' and the two images (one removed) underneath it.
• 'Mount St. Helens, shortly after the eruption of May 18, 1980.' — compare this with the first two images of the volcano before it exploded and you'll get some idea of how much of the side of the volcano blew out during the eruption.
• 'The slopes of Smith Creek valley, east of Mount St. Helens, show trees blown down by the May 18, 1980 lateral blast.'
• 'Denuded trees lay like matchsticks in the changed landscape around Mount St. Helens, shown two days after the eruption, on May 20, 1980.'
• The last image 'Satellites in orbit and scientists on the ground still monitor the mountain and track the recovery of Mt. St. Helens.' puts it all into perspective. Imagine me in the plane flying out of the crater (through airspace that had been previously solid rock) and been confronted with the 'matchstick' alignment of tree trunks radiating out from the new 'mouth' of the crater. The 'spokes of the wheel' alignment I mentioned was very obvious at this point.
Unfortunately, the panorama I saw from the plane's window was not be easily captured at the time by me or others as most of us didn't own cameras that could take panoramic images. The 4:3 aspect ratio of old camera images somewhat detracted from this amazing spectacle.
I can well attest to that. A year or so after the major eruption of Mount St. Helens on May 18, 1980, I had business in both Portland and Seattle and on that occasion I drove from Portland to Seattle rather than fly, as I'd normally do. (I'd been to Tektronix to whinge about ongoing problems we'd been having with a PAL 625 TV sync pulse generator—an interesting story in itself but I'll leave that for another time).
I live an ocean away—thousands of miles from Portland but I had an ulterior motive for renting a vehicle in Portland and driving to Seattle, as this time I wanted to visit and drive over the 'renewed' Tacoma Narrows bridge which replaced the infamous Galloping Gertie that failed in 1940—of which I'd learned so much about years earlier in structures and physics. Having a vehicle made that possible. Visiting Mt St Helens wasn't on my agenda—and I'd already seen it post the 1980 eruption from a commercial SFO/SEA flight although I did expect to see it in the distance to the east from the I5.
It was somewhat latish afternoon, 3:30–4:00 pm, when I arrived at my nearest point on the I5 to Mt St Helens and unexpectedly nearby there was a small airfield. Signs on the highway indicated that a company was offering joy flights to Mt St Helens, so on-the-spur-of-the-moment I decided to take the flight. Unfortunately, I was the only one wanting a flight at that time and the pilot told me that it was uneconomic to take only one person (two being the minimum) so I'd have to wait until additional sightseers turned up—and if that didn't happen soon (within 15 or so minutes) then it'd be too late in the day to fly! Anyway, I struck a deal at somewhat less than the amount for two people and we were on our way.
I don't need to describe this remarkable scene except to say it was spectacular—much more so than the somewhat limited view from the commercial jet; and anyone who's interested will already be familiar with the wonderful photos in National Geographic and elsewhere. However, one point I must comment on is that for mile after mile in this desolate lunar-mud-like landscape the remaining trunks of the flattened pine trees were all facing radially away from the exit point of the explosion like the spokes of a bicycle wheel, it was one of the strangest sights I've ever seen. There was no doubt that this was an extremely huge explosion.
After doing the standard joy flight, the pilot suggested that seeing I'd paid much more than the normal fare would I like him to take me closer to the crater. Gleefully, I agreed and we not only got closer to the crater but we actually flew around inside it — right, the crater is truly huge when one's actually inside it! When the author says it took him nearly 'six hours to walk out of the center of the crater' he not exaggerating one iota.
'Tis a damn shame photos aren't allowed on HN, otherwise I'd post some of my old slides taken from inside the crater (they're truly spectacular).