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How big was the Tonga eruption?

671 points| giuliomagnifico | 4 years ago |graphics.reuters.com | reply

259 comments

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[+] lnwlebjel|4 years ago|reply
I posted a visualization of the shock wave as a submission, but I"ll repost it here. This is a satellite measurement of integrated atmospheric water vapor (IIUC), so changes in the density of air change the integrated measurement, such that you can see the shock wave travel around half the globe.

https://cimss.ssec.wisc.edu/satellite-blog/images/2022/01/22...

(it take a few seconds to load, but I believe this is one of the most incredible things I've ever seen).

[+] LeoPanthera|4 years ago|reply
139MB is utter insanity for an animated GIF.

Crushing it with gifsicle can get it down to 125MB but clearly GIF is the wrong choice of format here.

Here's a HEVC compressed video version which is only 25M and suffers only extremely mild softness: http://david.gloveraoki.net/f/32M.mp4

It would probably be even better if I could work with the source video and not the gif version.

[+] nomel|4 years ago|reply
I wonder if the eruption could be heard on the exact opposite side of the globe, where the waves converged?

This would have been somewhere around 20.570000, 4.620000, in Guezzam, Algeria, according to: https://www.antipodesmap.com

[+] austincheney|4 years ago|reply
What’s happening immediately east of the eruption? There is a point water vapor variability in the center of the shock wave start and another single point of water vapor variability of equal size without a shockwave.
[+] fghorow|4 years ago|reply
Very cool!

Gives great intuition for geometric spreading on the surface of a sphere!

Modulo phase velocity and attenuation, it makes clear that the amplitude/energy density could actually increase past the great circle!

[+] dmissp|4 years ago|reply
Honest question - is this animation in real time, or sped up?
[+] RowanH|4 years ago|reply
Heard it go bang, 2600km away, echoing through the hills around our place at the top of the South Island of New Zealand. That's pretty staggering to think about it. Then to see other peoples Home Assistants around the world pick up the change in pressure on opposite sides of the planet. Mental, just mental...
[+] spartanatreyu|4 years ago|reply
I live on the beach on the East coast of Australia. We had a marine tsunami warning. We were a few floors up so I wasn't really worried about myself.

About 12ish hours after the initial eruption I thought that anything that was going to happened had all passed by hours ago and I was talking with friends online.

Randomly I started hearing this white noise kind of sound (it sounded like the bubbling water of a kettle without any whistling). I took my headphones off and opened my door trying to find the source of the noise, thinking that the kettle had turned on.

I looked outside and what was small surf conditions only 3 minutes before was extremely turbulent with white frothy waves moving in every direction. It looked like it was reacting to an earthquake but there was no movement in the ground. (I've felt an earthquake there before which is rare here but since our foundations are in the sands I've had the experience and could tell there was no earthquake in the ground on the morning after the eruption)

Since the waves were moving in every direction, some of them were colliding head on. When this happened and the peaks and troughs were interacting in the right way they were shooting out jets of water spray at my eye level about 15m above sea level (I could tell since they were intersecting the horizon from my perspective).

It continued for about a 30 seconds, calming down over another 30 seconds. After the surf had lowered itself to its previous levels, the whole top of the water going back about 50ish meters was covered in thick brown foam. All of the turbulent waves had dredged up the sand beneath it.

The foam slowly disappeared over about an hour with the last bits being the foam that ended up getting washed ashore and out of the water's reach.

[+] throwaway894345|4 years ago|reply
I've heard that the Krakatoa eruption was so loud that the sound wave reverberated around the globe several times. I assume that means if you're on exactly the other end of the world, the sound is coming at you from every direction? Similarly, no matter where you are on earth, the sound is coming at you from different directions at different times? Of course, I'm assuming that the sound wave was in audible frequencies which may or may not be the case...
[+] divbzero|4 years ago|reply
What did the “bang” sound like? Was it the sharp crack of thunder close by, the slower rumbling of distant thunder, the sound of fireworks exploding, or would some other description fit better?
[+] depereo|4 years ago|reply
My colleague's backyard weather station picked up the pressure wave in Christchurch several times as it repeatedly circled the globe.

Sea levels in the upper south were a little 'odd', trending higher and more variably than usual, even if not by that much, for a week.

[+] muti|4 years ago|reply
We also heard it while tramping on the thousand acre plateau just north of Murchison. It was very quiet, so we were lucky to be where we were with no noise pollution to drown it out.

Though at the time we had no clue what it was, we joked about being in the Tomorrow series timeline.

[+] dylanz|4 years ago|reply
Takaka or Motueka? I used to live in that area. Golden Bay has a pretty unique geographical layout!
[+] busyant|4 years ago|reply
This is an excellent lesson in how shitty my sense of geographic scale is.

I would have guessed that the size of the eruption was on par with the size of a small city.

[+] divbzero|4 years ago|reply
The Pacific Ocean is ginormous (I think that’s the technical term?) I often find myself surprised when I spin a globe (physical or virtual) and compare the expanse of the ocean to my neighborhood of the planet. The scale also makes the history of Polynesian seafaring all that more incredible.
[+] vanattab|4 years ago|reply
I mean your not wrong, the article is illustrating the mushroom cloud and ash cloud after 24 hours. So the explosive eruption its self is much smaller.
[+] michilehr|4 years ago|reply
My cheap weather station has recorded the blast wave three times.

https://michilehr.de/the-eruption-of-hunga-tonga-volcano-and...

[+] phist_mcgee|4 years ago|reply
I find the mix of your commas and periods in numbers a little confusing.

>305,8 m/s but also 8.7m and ~1.4 hPa.

I know that Europeans have a different notation to Americans, but is there a rule here I am missing?

[+] herpderperator|4 years ago|reply
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|4 years ago|reply
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 (?)

[+] fghorow|4 years ago|reply
For western US trained geoscientists, the Bishop Tuff [1] (from the ~750,000 years ago eruption of the Long Valley Caldera, near Mammoth Mtn. in California) is a "modern" comparable ashfall deposit.

This was quite a bit larger (edited to add: I meant in areal extent, not necc. volume erupted).

[1] https://en.wikipedia.org/wiki/Bishop_Tuff

[+] glup|4 years ago|reply
I was vacationing in Mammoth one time and started reading about the geology... quite a shock to find that basically everything to the east is a giant caldera [1]. Also 760,000 years ago is really quite recent on geologic time scales.

[1] https://en.wikipedia.org/wiki/Long_Valley_Caldera

[+] dheera|4 years ago|reply

[deleted]

[+] lambda_dn|4 years ago|reply
Wondering if any ships were destroyed by the eruption the scale makes me think there had to be?

Could Volcano eruptions be Earth's way of stabilizing climate change? i.e. sea water gets warmer and is no longer keeping the eruptions from occurring. Then the eruptions causes a drop in temperature due to the ash in the atmosphere?

[+] epolanski|4 years ago|reply
I'm no expert but I can't think of many reasons for a boat to be there.

I remember reading about that Malaysian flight that got lost few years ago in the indian ocean and apparently this area is so uncommon that the closest ships are often more than 1 thousand kilometers away.

The only ships that could be there would be local, but there was an eruption and tsunami alert issued the day before, so I guess that would only leave ships doing work related to the volcano itself.

[+] crakenzak|4 years ago|reply
> Then the eruptions causes a drop in temperature due to the ash in the atmosphere?

Interesting, this prompted me to read[1] into how it works and made me interested in why we don't pump sulfur dioxide into the atmosphere to help cool down the planet and buy us more time to transition off of CO2/CH4 emitting processes? Is it cost prohibitive? We already cloud seed pretty often so there's infrastructure in place for a large scale operation?

[1] https://scied.ucar.edu/learning-zone/how-climate-works/how-v...

[+] dylan604|4 years ago|reply
This looks like a tedious process that I would have totally done on my own had I thought of it. By that I mean the painstaking process of matting out each frame, then randomly placing it on places of the map, just because I could, just for the lulz. I'm not discounting it as "i could have thought of that", but appreciation for how useful it actually is.

Some people cannot grasp certain things without visuals, and this visual is one of those that definintely makes things clearer.

[+] Zash|4 years ago|reply
What I'm curious about is whether this was equivalent to, or larger than https://en.wikipedia.org/wiki/1883_eruption_of_Krakatoa

Also whether it will turn the sky red for months.

[+] phreeza|4 years ago|reply
My understanding is it's smaller even than Pinatubo, which happened in living memory, and significantly smaller than Krakatoa.
[+] notjustanymike|4 years ago|reply
The animation with it placed over Florida helped me understand, but also gave me a really good idea...
[+] baron816|4 years ago|reply
Is this expected to have a global climate impact?
[+] nabla9|4 years ago|reply
Globally event appears unlikely to have a significant cooling effect on temperatures globally, h

>"However, to date, it injected 'only' 0.4 Tg (400,000 tonnes) of sulphur dioxide into the atmosphere, which is not enough to result in significant surface cooling for this individual eruption. "Unless further eruptive activity occurs, we should not detect significant surface cooling. At present, hazards related to ash fallout are really the number one concern."

https://news.abs-cbn.com/spotlight/01/19/22/explainer-tonga-...

Local environmental harm: https://www.reuters.com/business/environment/tongas-volcanic...

[+] silisili|4 years ago|reply
Will this have a cooling effect on the Earth this year? I seem to remember global temperatures fell after the big one in the Philippines.
[+] twiddling|4 years ago|reply
The amount of sulfur injected into the atmosphere was quite small compared to the explosion of Pinatubo
[+] lr|4 years ago|reply
This is amazing, and superimposing it over other land masses really helps to illustrate the point. I think it would be incredibly helpful to compare it to interstellar events from comets, especially to the (supposed) impact of the comet from Don't Look Up...
[+] subsubzero|4 years ago|reply
Curious if this will cause a slight cooling of the earth's air temperature due to increased volcanic particles in the air. I had no idea of the size of this eruption and it looks absolutely enormous based on this article. It didn't mention how many metric tons were ejected into the atmosphere

Here is an article saying that after a eruption the air temperature rapidly cools for a while. Lets hope this doesn't wreck crop production.

https://www.scientificamerican.com/article/volcanoes-cooled-...

[+] burkaman|4 years ago|reply
Not this time apparently.

> Pinatubo erupted for several days, sending about 20 million tons of sulfur dioxide gas into the stratosphere, or upper atmosphere. There, the gas combined with water to create aerosol particles that reflected and scattered some of the sun’s rays, keeping them from hitting the surface. That had the effect of cooling the atmosphere by about 1 degree Fahrenheit (about half a degree Celsius) for several years. (It is also the mechanism of a controversial form of geoengineering: using planes or other means to continuously inject sulfur dioxide into the stratosphere to intentionally cool the planet.)

> But the Hunga eruption lasted only about 10 minutes, and satellite sensors in the days that followed measured about 400,000 tons of sulfur dioxide reaching the stratosphere. “The amount of SO2 released is much, much smaller than, say, Mount Pinatubo,” said Michael Manga, an earth sciences professor at the University of California, Berkeley. So unless the Hunga eruption resumes and continues at a similarly strong level, which is considered unlikely, it won’t have a global cooling effect.

- https://www.nytimes.com/2022/01/19/climate/scientists-tonga-...

[+] unethical_ban|4 years ago|reply
The gif time-lapse gives me some anxiety - it reminds me of the Sega game Space Harrier where the enemies come at you quickly, within a few frames.
[+] dr_dshiv|4 years ago|reply
And it still wasn't big enough to put sufficient sulfur dioxide in the atmosphere to have a noticeable cooling effect. Too bad :(

https://www.bbc.com/news/science-environment-60088413

[+] llampx|4 years ago|reply
Too bad? It would be extremely cool for one summer, ruining crops and causing famines and then back to hotter summers from next year onwards. How does that help anyone?
[+] DonHopkins|4 years ago|reply
Where are you when we need you, Rodney Dangerfield?

https://tmi.papost.org/the-pepsi-syndrome-saturday-night-liv...

Dr. Edna Casey: It means, Mrs. Carter, your husband, President Carter, has become [ camera zooms in on Dr. Edna Casey ] The amazing colossal president.

Rosalynn Carter: Well how big is he?

Dr. Edna Casey: Well Mrs. Carter, it’s difficult to comprehend just how big he is but to give you some idea, we’ve asked comedian Rodney Dangerfield to come along today to help explain it to you. Rodney?

[ Rodney Dangerfield enters ] Rodney Dangerfield: How do you do, how are you?

Ross Denton: Rodney, can you please tell us, how big is the president?

Rodney Dangerfield: Oh, he’s a big guy, I’ll tell you that, he’s a big guy. I tell you he’s so big, I saw him sitting in the George Washington bridge dangling his feet in the water! He’s a big guy!

Rosalynn Carter: Oh my God! Jimmy! Oh God!

Rodney Dangerfield: Oh, he’s big, I’ll tell you that, boy. He’s so big that when two girls make love to him at the same time, they never meet each other! He’s a big guy, I’ll tell you!

Rosalynn Carter: Oh no! Oh Jimmy! My Jimmy!

Rodney Dangerfield: I don’t want to upset you lady, he’s big, you know what I mean? Why he could have an affair with the Lincoln Tunnel! I mean, he’s really high! He’s big, I’ll tell you! He’s a big guy!

Rosalynn Carter: No! No! No!

Ross Denton: Rodney, thank you very much. You can go.

Rodney Dangerfield: It’s my pleasure. He’s way up there, lady! you know what I mean? [ goes off, leaving Rosalynn Carter very upset ]

[+] 2sk21|4 years ago|reply
I have been reading Termination shock by Neal Stephenson and this eruption reminded me of the main plot in tat book - injecting sulphur dioxide into the upper atmosphere to reduce heating. It will be interesting to track the effect of this eruption downwind.