Volcano thread

[bjdeming]

Dr. Hayakawa is a renowned volcanologist, retired now, I believe; Dr. Imura we have met. Both are knowledgeable but unofficial.

Hayakawa shows his interpretation of the fissure line, as of about half an hour ago.

Imura says, per X translation: "I wonder if it really spread toward the southwest (toward the center)? The northeastern crater rim feels like it has a small cone formed right at the edge, rather than the eruption fissure extending beyond the crater rim. I want to properly observe it from above."



Will see what JMA says today; it probably doesn't need a thread unless they go to 4, which requires evacuation of vulnerable people. The highest level, 5, calls for everybody in an affected area to evacuate.

 

[bjdeming]

JMA is keeping the alert at Level 3.

In this tweet, Dr. Imura confirms that a crater has opened outside the summit crater rim. The drone image in the retweeted post was taken shortly after the ash emission intensified yesterday. Dr. Hayakawa thought it was AI at first!



Per the GVP, population around this volcanic complex is:

Within 5 km Within 10 km Within 30 km Within 100 km

647 8,415 407,050 3,972,044

 

[bjdeming]

This paper gives us an idea of the sorts of things that officials and scientists are probably taking into account.

It focuses on Sakurajima and a hypothetical repeat of the 1914 VEI 4 Taisho eruption, but the Kirishimayama complex is close to the north shore of the bay that Sakurajima sits in, and this layperson can't see that it would make much difference if the location of the plinian-style eruption was there instead of at old "Cherry Blossom Island."

That is, apart from most of the ash falling on land, whereas Kagoshima Bay would take in much of Sakurajima's ashfall next to the volcano. On land, more ash would lead to more lahars and other short- and long-term problems.

No one can know yet if this Shinmoedake eruption will escalate to plinian levels, but just in case, it's an interesting paper.

Of note, in discussing their model the researchers note:

...It remains necessary to evacuate all vulnerable communities ... before of a large-scale explosive eruption, using the most reliable prediction results. However, the varying degree of uncertainties existed due to the time of the prediction and the quality of the wind forecast data influence the decision-making time frames. Following the current policy, forcing early evacuation orders (24 hr before an eruption) in most cases will result in a considerable number of unaccounted casualties and forced evacuees. Meanwhile, a delayed decision can also lead to fatal consequences due to late immobilization of residents. Uncertainties reside in each prediction state should be taken as a crucial input to select the most appropriate time for issuing a city-wide evacuation. The correct decision timing can ease the response planning, including the provision of additional shelters, the preparation of a greater quantity of relief goods, and the management of increased traffic flows, all of which can accrue substantial monetary costs...

 

[thundersnow]

Kobayashi

Maru.

“I don’t believe in a no-win scenario.”

(IYKYK, Trekkies )

 

[bjdeming]

Thank you, James T.

Also, Weather News reports (Japanese) that the uptick in activity that began late this afternoon (local time) continues.

It's raining, too, but there isn't yet enough ashfall AFAIK to soak it up into roof-breaking weight levels. Dr. Imura notes that the ash is washing into rice paddies.

As lagniappe, JMA has raised Aso's level to 2. Aso -- Nakadake Crater, actually -- is tens of miles north of Kirishimayama and in a different tectonic feature, not the Kagoshima Graben.

The eruption shown in the first post of this thread is from Nakadake.

 

[bjdeming]

Somehow stumbled through the language barrier to a list of live cams (Japanese) hosted by Kirishima City. Can't see much right now because of weather and night, but hopefully there will be some decent views tomorrow.