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How big was the Tonga eruption?

graphics.reuters.com

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Re: How big was the Tonga eruption?

#211

Post by Nekhrimah »

LeoPanthera wrote: post #111
RowanH wrote: post #79

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...

My back yard weather station picked up the shockwave here in the bay area: https://twitter.com/DavidCWG/status/1482451910154014720 I had no idea that was even possible. Crazy stuff.

> the bay area

It's always interesting that anyone who lives in a "Bay", refers to their local as THE Bay. For this phenomenon, which is documented as circling the globe, who knows where this could be!

Re: How big was the Tonga eruption?

#212

Post by jcun4128 »

LeoPanthera wrote: post #189
lnwlebjel wrote: post #178

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…

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.

Is interesting Gif size. With ShareX I get massive Gifs, but Kap on Mac I can get much smaller files (this is 14fps). Same for screentogif massive files... not sure what makes them so big.

Re: How big was the Tonga eruption?

#213

Post by fghorow »

lnwlebjel wrote: post #178

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…

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!

Re: How big was the Tonga eruption?

#214

Post by nomel »

lnwlebjel wrote: post #178

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…

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

Re: How big was the Tonga eruption?

#215

Post by jcims »

Railsify wrote: post #146
mkl wrote: post #127

Earlier quoted context omitted.

Even exactly on the other side of the world, the sound will reach you at different times from different directions due to different pressures, temperatures, mountains, etc. on the way.

But there would be a spot where the pressure waves would cross?

There's an animation of the antipode from this eruption arriving in northern Africa and it's interesting how distorted the incoming wavefront is.

https://twitter.com/weather_models/status/148300643675002880...

Re: How big was the Tonga eruption?

#216

Post by jcims »

phreeza wrote: post #32
Zash wrote: post #25

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.

My understanding is it's smaller even than Pinatubo, which happened in living memory, and significantly smaller than Krakatoa.

Peak power is roughly equivalent to that of Pinatubo apparently. The main difference is the duration, which was much longer for Pinatubo.

Re: How big was the Tonga eruption?

#217

Post by hffftz »

_qua wrote: post #183
lnwlebjel wrote: post #178

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…

This is a 140 MB gif ◑﹏◐ I hope you don't mind, I reuploaded as an MP4: https://imgur.com/BbaLE5U

No post body was provided.

Re: How big was the Tonga eruption?

#218

Post by mlindner »

LeoPanthera wrote: post #189
lnwlebjel wrote: post #178

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…

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.

Your video doesn't work either but the GIF worked fine. I get MIME type not found for yours.

Also the video is full of very fine scale noise. Something that won't compress by HEVC very well at all. You want a lossless compression method (or a very high perceptive index on HEVC).

Re: How big was the Tonga eruption?

#219

Post by [deleted] »

throwawayboise wrote: post #168
cwkoss wrote: post #157

Earlier quoted context omitted.

Is this a net 'good thing' for global human life because it will counterbalance anthropogenic climate change? (Probably still a significant net harm to Tongans I'd imagine :-( ) To what extent are the particles kicked up into the atmosphere a problem for life? Are they carcinogenic or respiratory risks?

I doubt it; it's a short-lived effect and probably doesn't really fall outside the normal range of year-to-year temperature variances.

[deleted]

Re: How big was the Tonga eruption?

#220

Post by mlindner »

ChrisClark wrote: post #156
vanattab wrote: post #118

Earlier quoted context omitted.

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.

After 1 hour actually, not 24 hours. But it is really mostly a huge ash cloud, not the explosion itself.

650 km in 1 hour (in diameter), aka 325 km/hr, aka about 1/4 the speed of sound. So yes that's basically the explosion.
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