Volcano thread

[bjdeming]

What is the location and the "big picture" (larger image showing weather patterns, etc.)?

 

[Atlantic]

What is the location and the "big picture" (larger image showing weather patterns, etc.)?

Here is the larger scale picture:

Western Australia just near Port Hedland is the near the place of the images I sent yesterday. It looks like a thunderstorm did the weird ripple, but if you look at other T-storms in the area; you don't really see the same effect. That is why I was wondering if it was volcano-caused.


It appears a monsoonal surge is going on actively, which is leading to low pressure development like 99S there in the image from yesterday.

 

[bjdeming]

Thanks! I see it now. My image interpretation skills are minimal -- mainly I look for ash (gray), unusual convection on radar, heat sources if the satellite view allows it, and explosion effects like gravity waves.

MArapi (southwest Sumatra) has been having occasional big blasts, but there likely would be more symmetry if a gravity wave was causing the ripple, though you never know at times when the atmosphere is active, as is clearly the case here

On looking up the local situation, it turns out that there are oodles of volcanoes here, including a recently discovered biggie, but they are all seamounts and AFAIK not erupting. Any eruptions there would be unlikely to affect the troposphere, though it would discolor water, launch pumice rafts, etc.

Sorry I can't be of more help.

 

[bjdeming]

Kilauea has been off and on; Mount Adams in Washington State has dozed off again, at least for now; but it looks like another US volcano might be getting ready to pop.

ALASKA VOLCANO OBSERVATORY INFORMATION STATEMENT
U.S. Geological Survey
Thursday, February 6, 2025, 4:55 PM AKST (Friday, February 7, 2025, 01:55 UTC)


SPURR (VNUM #313040)
61°17'56" N 152°15'14" W, Summit Elevation 11070 ft (3374 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW


Summary

• Volcanic unrest continues at Mount Spurr, an ice- and snow-covered volcano located on the west side of Cook Inlet approximately 75 miles (120 km) west of Anchorage. The most likely cause is new magma beneath the volcano.
• The duration (10 months) and nature of the unrest suggest that an eruption is possible. The most likely site of an eruption is the Crater Peak vent, which erupted in 1992 and 1953. It is less likely that an eruption would occur from Spurr summit, which last erupted several thousand years ago. Past Crater Peak eruptions were often explosive, and far-traveled ash clouds and ashfall can be expected if an eruption occurs.
• We expect to see additional seismic activity, gas emissions, and surface heating, as well as changes to surface deformation prior to an eruption, if one were to occur. Such stronger unrest may provide days to a few weeks of additional warning, but that is not certain.
• AVO is undertaking repairs to the monitoring network this week to improve data return. The current data flow allows us to track activity and detect changes that would precede an eruption. An observation and gas measurement flight is scheduled for February 7.

-- Full information statement

That 1992 eruption was a VEI 4, per the Global Volcanism Program page.

Anchorage Daily News is on it, and here is AVO's Spurr page with links to webcams, webicorders, etc. Note: In winter, Alaskan volcano cams sometimes go down but this one is up and faithfully showing -- darkness. Maybe the weather will allow some good daytime views.

 

[bjdeming]

There aren't any AVO videos on YouTube from their recent overflights, including one reportedly today, but here is their view of that 1992 eruption:



PS: In his book "Eruptions That Shook the World," Clive Oppenheimer succinctly describes how the atmosphere and plume are interacting in a plinian column like that:

What erupts at the vent is essentially a rock foam whose density is about ten times greater than that of air. However, the nascent plume, travelling at speeds in excess of 350 kilometres per hour, very rapidly ingests the surrounding air and heats it up The reduced density of hot air compensates for the dense ash particles and pumice suspended in the plume. Once sufficient air is sucked in and heated up, the plume becomes less dense than the ambient air and convects upwards. Its buoyancy will loft it to the height where it has the same density as the surrounding air. It may even overshoot this point thanks to its momentum but it will then sink back under gravity to its ‘ neutral density level’, flowing downwards and outwards to form a mushroom or umbrella-like cloud (Figure 2.3), before being dispersed by the wind...

 

[bjdeming]

Fire and ice -- Sicily's Etna is showing off again:



There are lots of live Etna cams online and now might be a good time to check them, especially at night, local time, because lava flows like this new one often develop into spectacular fountaining at the summit that (I hate to say it) puts even Kilauea to shame.

 

[bjdeming]

Lewotobi update: They moved the Aviation Code down to Orange on the 14th, although the volcano alert stays at the highest level, and news stories have shifted over to the refugee crisis. Darwin VAAC continues to report ongoing emissions.

This is closer to the level of activity Lewotobi had before November 3. However, Indonesia reportedly is planning to permanently resettle thousands of people.

I don't know what has gone on over the interval other than some fairly strong eruptions at active Lewotobi in recent weeks. However, reportedly Indonesia is calling for evacuations again. There is a major uptick in volcanic quakes.

Another paroxysm might be on the way.

Volcano Discovery has cams and other data here. In the most recent views, there is fire at the summit (not unusual) and a cloudy sky.

 

[bjdeming]

Reportedly, ever-active Fuego's activity near Guatemala City has picked up temporarily, though not, thankfully, to as extreme a degree as when it sent pyroclastic flows into several populated areas a few years ago.

As of about twenty minutes ago, Washington VAAC reported ash still present, but activity is decreasing.

Clouds conceal the volcano on webcam view now. Here's that cam's 2x save of some of the action:



Here's the Global Volcanism Program page and the local agency's page (Spanish).

 

[bjdeming]

Lewotobi finally went off -- as was the case last time, the first blast was powerful and then it settled down (but is still going strong, from all reports).

This time, no casualties reported thus far.

 

[bjdeming]

With some 27 million people around, someone will climb Popocatepetl no matter what the risk (it's active, at Yellow alert, explosive, and has a 12-km exclusion zone).

Some of them die or are horribly maimed, forcing others to come in and risk their lives saving the casualties and bringing out the bodies.

This was incredibly stupid but the video is very impressive and probably scientifically useful:



For reference, that elliptical crater measures 0.5 x 0.4 miles, and at the time of this 1992 ascent video (Spanish), was almost a thousand feet deep with remnants of a lava dome crater/crater lake at the bottom:

The 1994 eruption came through that old dome crater and so did the many domes and other activity that has occurred ever since.

<Layperson speculation>That tweet shows that this process has filled almost the whole crater and the eruptive vent has widened.

Thus far, though, Popo continues with its pulsing effusive/explosive activity separated by quiescent periods, unpredictably long or short, like the one that allowed that crazy person to climb up and get that video.

This could change without warning, since Popo is an open-conduit volcano and the precursors of an eruption are subtle as well as obscured by ongoing low-level activity.

This is worrying because no one can be sure if the volcano will give enough warning time before a possible shift into plinian mode (which it has done at least 4x since the last ice age ended) to put emergency evacuations into effect (experts suggest everything within about eight miles of the crater would be obliterated, and that does include thousands of people).

The almost full status now means the crater is unlikely to contain larger blasts and pyroclastic flows. Sigh. </layperson speculation>

 

[bjdeming]

Ulawun, in Papua New Guinea, had an impressive ash emission, just one, shown in this article. Rabaul Observatory discounts the possibility of further emission, but Ulawun is dangerous. Its stability is always a ?, too, given the flank fractures and low-level, almost continuous activity since its last rampage, in 2023, that probably has caused even more rock alteration and other changes.

Recent strong teleseismicity from Tonga and Myanmar might have "burped" it, so to speak, but even if that's the case, it deserves close watching now for a while, on the off chance that it does escalate or otherwise cause a problem.

Edit: Just came across this view of the blast --

 

[bjdeming]

Here's the volcano's GVP page (it's currently fairly quiet).

 

[bjdeming]

From the blog:

April 10, 2025, 5:45 p.m., Pacific: This Kamchatkan Mount St. Helens-style explosive volcano packs a punch (scroll down for a look at its 1956 plume), and a powerful eruption might be coming.

There are some towns nearby but at a distance. The main hazard would be to air traffic and any tourists that might be in the area.

Per the Global Volcanism Program page:

Most Recent Weekly Report: 2 April-8 April 2025
The Kamchatkan Volcanic Eruption Response Team (KVERT) reported that a thermal anomaly over Bezymianny was identified in satellite images during 30-31 March and 1-3 April. The volcano was obscured by weather clouds on the other days of the week. According to the Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), occasional ash plumes rose as high as 1.2 km above the summit and drifted NE and E. On most days, incandescent debris avalanches descended the SE flank and summit incandescence was visible during dark hours. Weather conditions occasionally obscured webcam and satellite views. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are reported in UTC; specific events are in local time where noted.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Institute of Volcanology and Seismology (IVS) of the Far Eastern Branch of the Russian Academy of Sciences (FEB RAS)

Per KVERT on April 9th:

An effusive eruption of the volcano continues, this is accompanied by gas-steam emissions. But the number of hot avalanches is gradually increasing. Satellite data by KVERT show a bright thermal anomaly over the volcano. Probably the volcano prepare for a strong explosive eruption. KVERT continues to monitor the Bezymianny volcano.
An effusive activity of the Bezymianny volcano is gradually increasing, probably the volcano is preparing for a strong explosive eruption. Ash explosions up to 10-15 km (32,800-49,200 ft) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.

KVERT is not given to overstatement.

Here's that 1956 plume image:

Tehnically, since this remote and (then) little-known Russian volcano did the whole sector collapse/landslide/lateral blast thing first, Mount St. Helens actually had a "Bezymianny-style" eruption, but that 1980 eruption is much more famous.

 

[Tennie]

From the blog:



KVERT is not given to overstatement.

Here's that 1956 plume image:

Tehnically, since this remote and (then) little-known Russian volcano did the whole sector collapse/landslide/lateral blast thing first, Mount St. Helens actually had a "Bezymianny-style" eruption, but that 1980 eruption is much more famous.

It helped that Mount St. Helens was in a fairly easily accessible area in a country where the sharing of information was/is more or less unrestricted, while practically the opposite was the case for Bezymianny...

 

[bjdeming]

The Cold War made a big difference, too. That "iron curtain" wasn't physically real, but it existed in everyone's mind. There was little to no communication of the sort we see today even in post-Ukraine invasion times (because of the transnational nature of volcanic hazard).

On the 11th, this year, Bezymianny had some pyroclastic flows:



KVERT's latest VONA, April 11th:

An extrusive-effusive eruption of the volcano increased significantly on 11 April: hot avalanches collapsed on the eastern slopes of the lava dome, and the ash from which rose up to 3-4 km a.s.l. Satellite data by KVERT showed an ash plume extending about 90 km to the north-east of the volcano.

An effusive activity of the Bezymianny volcano is gradually increasing, probably the volcano is preparing for a strong explosive eruption. Ash explosions up to 10-15 km (32,800-49,200 ft) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.

 

[bjdeming]

Here's today's daily update:

BEZYMIANNY VOLCANO (CAVW #300250)
55.97 N, 160.6 E; Elevation 2882 m (9453 ft)
Aviation Colour Code is ORANGE

An effusive eruption of the volcano is actively continuing: almost continuously hot avalanches collapse on the dome slopes. Satellite data by KVERT showed an ash plume extended for about 40-50 km to the southeast of the volcano; anLd a thermal anomaly over the volcano.

 

[bjdeming]

The Martinique Observatory reports (French) that today's 4-pointer there was tectonic. Mount Pelee has been at Yellow alert for a while but nothing significant seems to be stirring at the moment AFAIK.

In 1902, however, things were awful:

• Wikipedia
• Doyle Guides (I've read The Last Days of St. Pierre -- it's harrowing but good)
• German volcanologist Val Troll's special last year on the 1902 catastrophe:

 

[bjdeming]

That's recent, but thus far KVERT hasn't issued a VONA on the website. Their update for the 19th was the same as in previous days -- lava effusion (the blocky kind, BTW, not runny red Hawaiian-style lava) and pyroclastic flows, with Bezymianny still at Orange aviation code.

 

[bjdeming]

Two VONAs on the KVERT site at present, issued about six hours apart. However, they were not the possible "big one" -- Bezymianny is still at Orange code.

 

[bjdeming]

Still in Kamchatka: Of note, nearby Klyuchevskoy, a frequent erupter, just woke up again. It's having Strombolian explosions, KVERT notes, presumably a lot like these in an 11-year-old video:



That's a real interesting area. Bezymianny is part of the Klyuchevskoy group, with extinct Kamen in between.

You can see them lined up, though a ridge hides all but tiny parts of the pyramidal summits of Kamen and Klyuchevskoy shown here to the left of the Big B, which is having a moderately big one in 2022:



Sheveluch, to the north, makes international headlines intermittently, but it might not be part of the Klyuchevskoy group (have to check my notes). To the south, Plosky Tolbachik is in the group, I think, even though it's a different kind of volcano, more of a Hawaii-in-Siberia thing as this 2012 pano shows:



What's really interesting, speaking of Hawaii, is that this group of volcanoes has formed above the part of the subducting Pacific tectonic plate that's carrying down the last northerly remnants of the Hawaiian Islands/Emperor Seamounts chain PLUS it is near the junction with the Aleutian Islands where the Pacific plate angles into subduction from a slightly different direction -- some researchers suggest that this has torn the plate and hotter mantle material is welling up, giving us the Klyuchevskoy group and Sheveluch.

(Other volcanoes in Kamchatka have their own stories.)