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Volcanic Winter

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Posts posted by Volcanic Winter

  1. 4 hours ago, LibertyBell said:

    No one has been able to answer this for me.... why did they create an entirely new scale? Why not just plug in the EF values into the old F scale, I actually like that scale much better.

     

    As best I understand it was due to engineering reasons, they determined the old F rating wind speeds were exaggerated for the damage they indicated (IE lesser winds produced equivalent damage). Hence they changed to the Enhanced Fujita. 
     

    However I heard somewhere after the April 2011 super outbreak they began changing the criteria / damage thresholds that would allow a tornado to be classified as an EF5, and I heard essentially that the requirements are so strict as to be nearly impossible. It had lots of engineering arguments that are above me, but I thought it was interesting. They were suggesting we wouldn’t be seeing many EF5’s in the future with this new method solely for giving out an EF5 rating. Again, don’t know how ultimately valid this is but it was compellingly presented. I’ll look for the page I saw this on and link it if I can come across it. Has a lot of analysis of the mid to late 2010’s EF4’s that maybe could’ve been EF5 strength. 

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  2. Was just thinking about when we’d see the next EF5. I had heard / read some criticisms that the NWS essentially redefined the damage necessary to classify a tornado as an EF5 as to be almost impossible. Basically it was stated that many historic EF and F5’s would be an EF4 with the new survey methods employed. 

    Don’t know how valid that is, but the arguments I saw made sense in context and with examples. 

    A few of the EF4’s since Moore would probably have been an EF5 with the less strict survey methods. 

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  3. The larger eruption I'm hearing was 0.94 cubic kilometers, combining with the earlier 0.40 cubic kilometers of the eruption on the 17th, this event is a clear VEI 5 overall and actually larger than St Helens in 1980, though that erupted 1.2 cubic kilometers in one sustained eruption.

    Still, this is a very, very significant event. Usually one eruption per decade will reach VEI 5 levels.

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  4. And just to give a sense of how insane the VEI scale and explosive volcanism in general gets, assuming Ruang hits a minimal VEI 5 of 1 cubic kilometer (St Helens was 1.2 cubic kilometer, much of that erupted laterally), it would have to further erupt 10x more volume to reach a minimal VEI 6 (around what Hunga Tonga did, and a little less than Pinatubo).

    From current levels (again assuming 1 cubic kilometer - a minimal VEI 5), it would have to erupt 100x more material to reach a VEI 7, 150x in the case of Tambora. 

    To reach a ‘supereruption’ at VEI 8, it would need 1000x its current erupted volume. 

    The Toba supereruption 75kya was 3500-5000x this hypothetical VEI 5 Ruang eruption. 

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  5. 1 hour ago, donsutherland1 said:

    It will depend how much was injected into the stratosphere. The earlier eruption produced about 0.5 terragrams of sulfur dioxide. About 5 terragrams reaching the stratosphere is required to have a significant short-term climate impact.

    https://earthobservatory.nasa.gov/images/152716/a-blanket-of-ash-from-ruang

    image.png.71631565b42b7d5db066d9f303dd591c.png

    I haven't seen any data on the most recent eruption, yet, but it should be posted here in coming days:

    https://so2.gsfc.nasa.gov/measures.html

    Note: The chart in the above link shows total sulfur dioxide emissions, not solely those that reached the stratosphere.

    Absolutely Don. 
     

    I see they revised the first blast up to half a Tg up from 0.3 from the initial estimate. I can’t overstate how impressive this entire sequence has been. The first blast was the destruction of the existing lava dome (think a plug of viscous magma that hardens into a dome shape blocking the conduit and helping to increase pressure in the system). It was notably intense transpiring only over a couple hours and outputting mid VEI 4 volume; that’s extremely impressive. 

    Most volcanoes would then go quiet and enter a prolonged period of repose after such a blast. Instead, Ruang extruded another, even larger lava dome which hardened into another plug. The injection of fresh magma into the chambers below apparently never stopped, and Ruang built back up like a pressure cooker. This second blast was utterly spectacular, the amount of power behind blasts of that nature is bewildering. 

    Like Grimsvotn in 2011, most VEI 4-5 plinian eruptions are only moderately intense and transpire over 12 or more hours. You have a generally sustained eruption column that may occasionally collapse into pyroclastic flows down the flanks of the system. 

    Ruang just did everything all at once, twice!

    • Like 6
  6. @snowman19
     

    This eruption is even larger than the first, this is incredible. The first was a solid VEI 4 by itself with about .40 cubic kilometers of erupted material. Given this blast now is even larger, there really is a chance for a collective VEI 5 event here. 

    These are incredible sequences of lava dome creation and destruction, like Shiveluch last year but even larger and more powerful.

    image.thumb.jpeg.038ce35d1077a28f8c39f9edc1faa8c5.jpeg

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  7. 59 minutes ago, TJW014 said:

    Started off at 27. Radiational cooling doing its thing in the Pine Barrens. Probably get to around 60 before the inevitable sea breeze pushes in. Good to see the sun out again

    Yup, we both have that chilly Pine Barrens night time microclimate. I’ve been amazed just how consistently chilly it gets down here on clear nights. Pretty sure we were right around 0-2 during one of those stronger Arctic pushes in the mid 2010’s, but it was before I had a reliable weather station on my property. 

    I’m backed up to woods off 37 near the western border with Manchester / Lakehurst. Can be a pretty chilly little pocket, and slightly more elevated than the downtown area. I’m at about 60-70ft. 

  8. https://www.volcanodiscovery.com/ruang/news/239570/Ruang-volcano-Sulawesi-Sangihe-Islands-Indonesia-eruption-plume-drifts-over-1000-km-currently-over-b.html

    "GEMS measurements of sulfur dioxide (SO₂) from the eruption on April 18th show notable data gaps in areas with high SO₂ column amounts, likely due to clouds or ash. A very preliminary estimate suggests a total sulfur dioxide mass of approximately 0.3 teragrams (Tg)."

    A preliminary estimate of the sulfur release suggests about 0.3 Tg's, which is about spot on for a VEI 4. Shouldn't be a major climate player unless these figures are way off. El Chichon did ~7 Tg's as lower end VEI 5, Pinatubo was more than double that. We know HTHH was huge but atypical with most of the sulfur ending up in the ocean, initial estimates put it about 0.4 Tg but I've seen it revised as high as 1-2 Tg's.

    What makes this Ruang eruption interesting is actually in how fast/intense the main blast was, which was only over a period of a couple hours. The other precursor eruptions were much smaller so the main volume of the event was in the big boom.

    Just my thoughts / speculation at this point.

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  9. 6 hours ago, snowman19 said:

    @Volcanic Winter @bluewave Just to add, there is some speculation that this eruption may reach a VEI 6. Wouldn’t that be unprecedented to have 2 VEI 6 eruptions this close together? I know Hunga Tonga was a 6….

    IMHO that kind of speculation is very premature. As mentioned it can be deceiving in both directions. 

    Smart people were calling HTHH a 3-4 a day after it happened thinking the entire column was steam (it wasn’t, 1.9 cubic kilometers of ash in it which is already well into VEI 5 territory). And hidden underwater was another 6-8 cubic kilometers of ignimbrite (massive pyroclastic flows from caldera collapse). 

    Just IMO and I’m not caught up on this one yet. 

    To answer your question it would be rare but not even historically without precedent. Six years before Tambora’s VEI 7 in 1815, there was a mystery eruption from a not fully identified volcano that was at least a VEI 6 in 1809. A six and a seven that close together is pretty mind boggling. And remember a 6 could be 10 cubic kilometers like Pinatubo or 99 cubic kilometers, basically a near 7. At VEI 6 level is when the scale sort of breaks in terms of perception. Things just start getting really ridiculous massive. 

  10. 6 hours ago, snowman19 said:

    This *could* potentially have big stratospheric implications….major tropical volcanic eruption ongoing. If this thing pumps enough sulfate aerosols into the stratosphere, it could conceivably have effects on next winter’s SPV and NAM (AO) state. This needs to be followed closely @Volcanic Winter
     

    Thank you Snowman, I’m just getting caught up on this. One of the few days I’m not being a compulsive volcano obsessive something significant happens. Hoping for the safety of everyone impacted by this, I believe there’s a few hundred living on that island?

    I’ll post when I’m caught up with accurate info, I tend to avoid speculation. I also don’t like trying to analyze the size of an event while it’s occurring and before all the data is reviewed, it can be deceiving in both directions. 

    I’m trying to verify column height, something to the level of a VEI 5 typically has no problem clearing 20km for a sustained period of time and I’m seeing this latest blast was about 17km based on sources I’m looking at now. Also unclear of the duration of that blast, which matters in terms of volume which is ultimately what determines VEI at this level.  The satellite imagery is impressive though, trying to verify. 

    In terms of SO2 loading in the stratosphere, we want to see something similar to El Chichon’s ~7 Tg’s for detectable surface impacts. Probably at least 4-5+. 

  11. On 4/8/2024 at 7:59 PM, Nibor said:

    The path of totality goes across Hornstrandir one of Iceland's most remote national parks. You can only get to it by boat. In the early stages of planning a trip there in 2026 with some backpacking friends. 

    Wow, enjoy!!! Hornstrandir is unbelievably gorgeous and looks like you’re in Middle Earth. We go in winter pretty exclusively so Hornstrandir hasn’t been an option for us, but it’s a very committed trip to be sure. Be safe and have the very best time, I’m jealous!

    • Like 1
  12. IMG_4951.thumb.jpeg.4d3476a01b78dc32aae518a1fafe8552.jpeg

    Partial shot, I actually like how the clouds enhance visibility in my iPhone lens. Wasn’t really able to be captured otherwise at 88-90%, whatever exactly the north half of Jersey was. Still very cool!

    • Like 3
  13. @LibertyBell


    Did you know the Palisades are a local outcrop of one of the largest flood basalt eruptions in the past billion years? CAMP - Central Atlantic Magmatic Province, an enormous series of lava flow eruptions along the seams of Pangea when it first began to break apart. We actually have some interesting geology in the region apart from the boring sedimentary coastal plain. At one point the Appalachians were earth’s Himalayas of the distant past, now long eroded to a mere shadow of their former enormity. 

    We know flood basalts are most common under large stretches of continental crust (especially when the continents are in a supercontinent configuration), often coinciding with the rifting episodes that ultimately split them apart. It’s why a hypothesized location for earth’s next flood basalt is the East African Rift, where Somalia is slowly being separated from continental Africa and most of Africa’s extant volcanism is currently located. The Virunga plateau is a large magma bulge, and there could be something of a proto-plume down there which would one day yield a major flood basalt episode. This is like hundreds of thousands to millions of years in the future though. 

    There hasn’t been a flood basalt episode on earth since the Columbia River Basalts of the PNW ~16mya, which is the hypothesized birth of the Yellowstone plume which traces to the Yellowstone supervolcano today. 
     

    There’s also a supposed growing magma body under parts of New England, and the Adirondacks are some odd magmatic uplift feature and could also be a small plume in its early stages. Who knows what the distant future could hold there, could be some major volcanic episodes if the inflation that made the mountains continues. 

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  14. I was not aware the Ramapo fault could harbor a mag 6+ risk:

    https://www.earth.columbia.edu/articles/view/2235

    That would have to be a ‘full margin rupture,’ or the majority of the length of the fault slipping at once. These ancient ‘inactive’ faults from past geological eras are tricky because they can be dormant for a very long time and suddenly awaken. Think the New Madrid quakes which were catastrophic, though we wouldn’t see anything reaching that level here. A 6-7 though would obviously be very damaging in this region. It’s interesting because we’re so far away from a plate boundary (hence the Ramapo is an ancient fault from the time of Pangea), it’s believed stress is slowly loaded on the fault by the mid Atlantic ridge under Iceland, all that distance from here. It makes total sense, it’s just not very obvious.  

    My personal opinion is that we have no idea of the recurrence time, it could be thousands of years between those kind of full margin quakes at a slow fault like this, so it’s most likely not something we’d have to worry about in our lifetimes. 

    Still, interesting.

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  15. 9 minutes ago, LibertyBell said:

    Can we find a connection between these and heavy rainfalls that happened just prior?  August 2011 was a very rainy month.  We've been in a very rainy pattern now too.

    I remember reading scientific papers linking heavy rainfalls and earthquakes-- is it a possibility?

    I’m not super well versed in all that, the majority of what I study about earthquakes are in relation to volcanoes. 

    I do think that sounds plausible, an over abundance of ground water saturating those deep inactive faults and possibly lubricating or shifting the mass balance enough to slip a bit? Sure, sounds plausible but I can’t really comment further. 

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