General Volcanic Activity Thread!

[Climate Man]

3 minutes ago, The PIT said:

I wonder why different speeds? I would thought the shock wave would have had the same speed.

Different distance depending on which way around?

[matty40s]

1 minute ago, Climate Man said:

Different distance depending on which way around?

Shortest distance was 16k miles, the long way round was 24k miles.

[BornFromTheVoid]

 

[The PIT]

From the twitter feed explaining this .

"The first travelling ~16000km, the second going the long way around and travelling ~24000km!

 

[swfc]

Amazing that this event has received so little coverage. That said the covid "party" ie government more important

[The PIT]

Okay I guess the speed difference is due the distance travelled and the wave slowing down as it travels.

The news coverage has been quite widespread however since there's little or no communication there hasn't been any real new news to add so they haven't got much to update.

The red cross seem to think the damage isn't as severe as expected which is good news if accurate I'll guess it will be days before the amount of damage is truly realised.

 

[weatherobsuk]

Tonga eruption: Before and after images show extent of destruction | Daily Mail Online

WWW.DAILYMAIL.CO.UK

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The Pacific island nation of Tonga was devastated by a huge eruption of the underwater Hunga-Tonga volcano late Saturday, which sent a huge plume of ash into the atmosphere and triggered a...

 

[Guest]

5 minutes ago, The PIT said:

Okay I guess the speed difference is due the distance travelled and the wave slowing down as it travels.

The news coverage has been quite widespread however since there's little or no communication there hasn't been any real new news to add so they haven't got much to update.

The red cross seem to think the damage isn't as severe as expected which is good news if accurate I'll guess it will be days before the amount of damage is truly realised.

 

Could also be the blast was focused at an angle? 

[SnowBear]

44 minutes ago, The PIT said:

I wonder why different speeds? I would thought the shock wave would have had the same speed.

The first register on the graphs will be a direct shock wave travelling the shortest route from the volcano, the second will have interference from the meeting of the wave from all directions in Algiers. So the second long route blip registered in graphs will have passed antipode which means some of that energy will have been cancelled as it meets the energy of the first blip registered, this will also slow it down. 

44 minutes ago, The PIT said:

Double quote box error

 

Edited January 17, 2022 by SnowBear
Double post, tidied up as best I can

[matty40s]

13 minutes ago, swfc said:

Amazing that this event has received so little coverage. That said the covid "party" ie government more important

Plenty of coverage on here!!

Tonga has to wait 2 weeks for the nearest internet cable laying ship to arrive before it can fully rejoin the WWW so news locally is limited to a few expensive satellite internet connections and a much damaged telephone system.

 

[Summerstorm]

5 hours ago, swebby said:

In regards to risk and putting aside VEI7+ eruptions that are incredibly unlikely to occur anywhere on the globe in our lifetimes.

A standard moderate sized eruption of either Campi Flegrei or Mount Vesuvius would be catastrophic at a local level.  The expansion of Naples and the surrounding area now stands at over 3 million people! With development ongoing high on the flanks of Vesuvius, if there is insufficient notice (weeks) of an eruption, the consequences are hard to imagine.

That's what my thoughts were that Vesuvius hasn't erupted for 78 years the duration between eruptions are between 70-140 years so theoretically It could explode any day although I'd imagine it might be a few decades before that happens. VEI 7 eruptions are rare and occur once a millennia on average even VEI 6 eruptions only occur two or three times a century at most. 

[SnowBear]

I think these two graphics from The Converstation article I posted yesterday show just how big the caldera is under the sea, and how much of the northern rim has now gone. 

Going by the second graphic my guess would be a landslide at that northern end northwards. We saw a sat image from a day or so before the big explosion, where most of the centre between the east and the west long term islands had slipped or sunk during the first smaller explosive eruption. If this allowed sea water to enter the magma chamber of the main caldera in the centre, the result was the larger explosion we saw later. 

Edited January 17, 2022 by SnowBear

[crimsone]

For those of you using google chrome (or another browser that'll translate), this article was very recently posted by Dr Janine Krippner - 

La grande eruzione del vulcano Hunga Tonga – Hunga Ha’apai - INGVvulcani

INGVVULCANI.COM

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Una nube simile a un fungo atomico, detonazioni fino a migliaia di chilometri, tsunami. E' l' eruzione del vulcano Hunga Tonga-Hunga Ha’apai

 

[Guest]

Noise on Twitter suggesting some of tsunami buoys are returning odd data suggesting something else may of happened. 
 

 

[crimsone]

19 minutes ago, Alderc said:

Noise on Twitter suggesting some of tsunami buoys are returning odd data suggesting something else may of happened. 

I watched the video with skepticism until at 1:42 he said that it's hard to find satellite confirmation because it's quite dark.

Yeh, nah.

I'll wait for a trusted source to say something. If something is out there NZ or Fiji will pick it up in short order (NZ monitors islands out towards that direction), and it's well into the morning here (Tonga is on the same time zone) .

[Ross90]

Godzilla has awoken...  you wouldn't be surprised if the conspiracy theorists jumped on that one, i'm surprised nobody has suggested nuclear testing yet. 

[booferking]

23 minutes ago, Ross90 said:

Godzilla has awoken...  you wouldn't be surprised if the conspiracy theorists jumped on that one, i'm surprised nobody has suggested nuclear testing yet. 

Don't worry my lunatic of a friend already on the rocket conspiracy sent me a video earlier today yep he believes on a flat earth also along with many other things.

[Evening thunder]

More pressure wobbles today, I wonder if it could be pressure waves/ripples coming around a second time or just caused by something else?

Edit: I believe it is.. two smaller blips towards the end of my graph are a similar distance apart from the first two blips near the start of the graph

About 36 hours to travel all the way around the globe since the first passage.. Seems about right if the first wave took 14.5 hours to travel about 16,500km, a bit less than half way around.

Using rough figures

16,500km/14.5 hours = 1,137 km/h
40,075km/36 hours = 1,113 km/h

gives pretty much the same speed for the pressure wave so it's consistent with the theory.

Edited January 17, 2022 by Evening thunder

[crimsone]

Tonga tsunami: Two deaths confirmed, MFAT says | Stuff.co.nz

WWW.STUFF.CO.NZ

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NZ Government has confirmed two people have died following an eruption and tsunami that devastated the island nation.

There is, of course, lso the matter of that distress signal, and then the fact that the comms cable is still out.

Read a report earlier that 200 people were brushing ash from the runway at Nuku'alofa to allow an Aussie aid aircraft to land

[crimsone]

Not sure if this (or my previous link) is geoblocked? If memory serves, at least one of them is?
 

 

[Guest]

9 hours ago, Alderc said:

Noise on Twitter suggesting some of tsunami buoys are returning odd data suggesting something else may of happened. 
 

 

This was a load of nonsense. Seems like people post this for likes…..there were lots of posts like this last night. Sad really.

[SnowBear]

3 hours ago, crimsone said:

Not sure if this (or my previous link) is geoblocked? If memory serves, at least one of them is?
 

 

First is OK in the UK, second is indeed geoblocked.

[crimsone]

Tonga eruption: Satellite images show island covered in ash from Hunga-Tonga-Hunga-Ha'apai volcano

NEWS.SKY.COM

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A plume of ash can be seen rising from Hunga-Tonga-Hunga-Ha'apai volcano in images taken before the eruption, with the volcanic island appearing to have all but disappeared afterwards.

 

[SnowBear]

11 hours ago, crimsone said:

For those of you using google chrome (or another browser that'll translate), this article was very recently posted by Dr Janine Krippner - 

La grande eruzione del vulcano Hunga Tonga – Hunga Ha’apai - INGVvulcani

INGVVULCANI.COM

---

Una nube simile a un fungo atomico, detonazioni fino a migliaia di chilometri, tsunami. E' l' eruzione del vulcano Hunga Tonga-Hunga Ha’apai

 

An interesting paragraph here.. 

The sound of the explosions is not only perceived in the nearest islands, but also clearly in New Zealand, at distances between 1600 and 2000 km, and several hours later even in Alaska , more than 9300 km away! This far exceeds the distance at which the famous Krakatau detonations were heard in 1883 (approximately 4000 km), hitherto considered the "loudest sound ever heard".

It will be interesting to see where they eventually rank this eruption in terms of dB noise level compared to Krakatoa. (310 dB) 

Distance travelled may not be a very good indicator due to more people possibly living in Alaska now so perhaps more widely noticed, also atmospherics across the Pacific aiding pressure wave propagation. Its still an amazing distance though. 

[crimsone]