Galileo 1998 image of Io. This one shows two active plumes. Pillan Patera plume is at the upper limb of the moon. It is 140 km tall. Second active plume is Prometheus Patera center bottom near the terminator between dark and light
By the end of Galileo, over 160 active hot spots were identified. Eruptions were classified into lava flows, lava lakes, lava fountains, sheet flows, and activity within paterae, which could have been lava lakes, ponded lava flows or active lava flows. There is no distribution of volcanic activity that appears to be driven by global tectonics, leading to the conclusion that the crust is for the most part immobile. Paterae nearer the poles are fewer in number and larger in size than those at lower latitudes. This may mean the style of volcanism varies on a global scale.
Active volcanism from mid-sized hot spots deposit an estimate 43 km3/year on the surface. Most of the resurfacing comes via plume deposits.
Side view of Pele Patera and active plume. Image courtesy NASA JPL via Solarviews.com
Pele Patera
Pele is one of the most distinctive of Io’s volcanoes. It has both a massive lava lake and a persistent plume over 300 – 400 km high. The reddish deposits are 1,200 km across and were laid down by the plume. They are rich in sulfur and SO2. Dark pyroclastic material is closer to the vent. The shape of the plume has changed over time. It was not seen by Voyager 2 and may have shifted into a more gas-rich stealth plume. No other giant plume is as persistent as the one from Pele.
Highest resolution image of Pele Patera from Voyager in 1979. Patera and lava lake are to the north (top of picture) of the mountains (Danube Planum). Image shows dark lava flows and light pyroclastic materials. Screen capture from Radebaugh et al 2003
Thermal imagery of Pele shows it to be relatively hotter and long-lived hot spot on a decades long scale. Closer observations by Galileo led to the conclusion that Pele has a vigorous eruption under way. There are no lava flows emplaced, meaning that Pele has an active lava lake with at least part of its surface being regularly overturned. IR emissions are measured from 17 km2, equivalent to a lava lake 4.5 km in diameter, though the actual lake is likely larger. There are no extensive, cooling lava flows at Pele observed by IR.
Nighttime Galileo thermal image of Pele Patera. Top image is original. Digital noise in the top photo is caused by the high radiation environment. This noise is digitally removed by combining multiple images. Lava lake is to the right. Hotspot chain center and left. It may include plume locations at the bleeding hotspots. Suspect most of the hotspot chain is lava flows. Screen capture from Radebaugh et al 2003
A lava lake like this is thought to be the top of an active magma column. There is one other spot on Io that looks like Pele in IR observations, Janus Patera. It does not have a plume. The presence of volatiles in the plume make Pele unique on Io. These are thought to be added to the magma on the way to the surface, perhaps encountering a liquid SO2 “aquifer” a short distance below the surface.
While active lava lakes are present on earth at Erta Ale and Erebus, the best analog for Pele is Kilauea.
Map of Pillan Patera and surrounding region. Visible is the major plume deposit from Pele and mountains to the north of Pillan. Image courtesy NASA JPL via Gish Bar Times
Pillan Paterae
Eruptions at the next two locations are much different from Pele. Pillan began explosively and transitioned to an effusive eruption. Pillan erupted ultramafic magmas, high in magnesium. These dominated eruptions on earth billions of years ago, giving volcanologists perhaps another analog to study.
While there is an atmosphere on Io, it is very thin, so expansion of volatiles into the vacuum drives explosive activity. Expansion of a small amount of gas in a magma column can create exit velocities over 1 km/sec with plume tops 350 km high. On the moon, explosive eruptions were driven by CO2, on the earth, water and CO2, while on Io, the volatile is SO2. This all means that a huge volume of lava can be erupted from a fissure in a short time, perhaps 1 km3 in a couple hours.
Galileo image of Pele – Pillan region. Locations of recent eruptions annotated. NASA JPL mosaic from combined Galileo – Voyager database. Williams et al, 2011
The 1997 Pillan eruption started explosively and was so vigorous that it saturated the Galileo IR sensor. It put a dusty plume to at least 140 km. The combination of dusty plume and IR led to the conclusion that the source was a massive lava fountain outbreak. The plume deposited material 200 km from the vent. Lava flows broke out from heavily fractured mountains, entered the Patera eventually covering 5,600 km2 with an estimated 56 km3 volume. Pyroclastics covered 125,000 km2. All of this was done in an eruption lasting 99 – 167 days.
Tvashtar Paterae and surrounding region. Image courtesy NASA JPL via Gish Bar Times
Tvashtar Paterae
Also began with a spectacular lava-fountain episode in 1999. This one was also sufficiently vigorous to overload the IR sensor and cause image saturation. Tvastar is a chain of nested calderas. The eruption deposited red material over 900 km in diameter. The plume was over 400 km high. The eruption took two years to complete. Flow rate estimates from the 25 km long fissure are very close to the maximum rate that can ever be erupted from magma in any fissure eruption on Io or earth.
Earth analogs to these two eruptions would be Loki Skaftar Fires in 1783 – 1784 and The Columbia River Flood Basalts, with the Columbia River basalts being closest in total volume erupted from these two systems. Io has lava flow fields considerably larger than Pillan or Tvashtar, one of which is still warm. These may be the Ionian equivalent of terrestrial flood basalts.
Prometheus Patera. Lava lake is upper right. Fissure to the south of caldera extends 90 km to the west. Bright patches are likely SO2. Two of these patches near the top left edge of the lava have dark blue haze and active plumes. Newly erupted lava is interacting with SO2 snow. Image courtesy NASA JPL via Giovanni Leone, 2007
Prometheus Patera
Prometheus is one of the most persistent active volcanoes with an active plume observed as long as we have looked at it. The plume is thought to be caused by boiling off SO2 deposits by advancing lava flow fronts. Lava flows appear to be laminar, thin, and mobile, covering previous flows. New flows covered 60 km2 in 4 months during 2000. Individual flows are thought to be in the vicinity of 1 m thick. New flows are almost entirely limited to the existing flow field. This activity is most similar to Kilauea.
There are two plumes at Prometheus. One is a small sulfur-rich plume from the magma source, the other SO2-rich plume centered on the westernmost flows. Flows from here covered over 6,700 km2 from 1983 – 2004.
Amirani Patera. Patera is in the center. Flow field extends north and south. NASA JPL image courtesy Gish Bar Times
Amirani Patera
Amirani is another persistent hot spot with a flow field. It is the largest active flow field in the solar system, over 300 km long. 620 km2 of new lava was emplaced in 134 days in 2000. This system had intermittent Prometheus-style plume activity centered on the flow front. It is difficult to determine how many individual active centers feed this system.
Loki Patera and lava sea. Black portion to the right of the image is the active magma sea. Plume is to the north of the magma sea. Deposits surround the complex. Lava flows are visible to the west (center of the image). NASA JPL image courtesy New Scientist
Loki Patera
Loki is one of the most powerful IR emitters on the entire moon, totaling 10 – 25% of all thermal emissions from Io. Yet this emission comes from less than 0.1% of the total surface area. This means that it must be a very active region. This high output also makes it easy to observe from earth.
Unlike almost all other large volcanic sites, this activity has not changed Loki’s appearance over the years, which is yet another paradox. The Loki Patera is around 200 km in diameter. There is a feature that looks like a raft covering perhaps 25% of the area of the patera. The island may be a foundered mountain range or a resurgent dome. If it is the latter, it will be the only dome discovered on Io. While there was some visible difference in the patera in the months between Voyager 1 and 2, its appearance returned to that of Voyager 1 during Galileo’s stay in the system.
Heat map of Loki Patera lava lake. Surface is hotter to the SE where surface overturn began and hotter magma was more recently exposed. Entire lake surface overturns in about 3 months. Katherine de Kleer graphic via Berkeley News
Two plumes were observed around 200 km north of Loki by the Voyagers. They were not observed by Galileo.
Changes in the floor of the patera itself have been observed mainly by movement of IR peaks. These are interpreted as either resurfacing the floor with new lavas or overturning of the crust on a massive lava lake. The Davies book leans toward the lava lake explanation, which would make it the largest active lava lake in the solar system. Close IR sensor passes with Galileo gathered data that could only be explained by the foundering lava lake crust model. Foundering takes place in roughly a 540-day long cycle. Given its size, Loki has been described as a magma sea rather than a lava lake. There is no evidence of convection on the lake. The crust passively sinks without lateral movement.
Culann Patera. Unknown whether the green is a coating of sulfur or silicic materials. Image courtesy NASA JPL 1999
Other Volcanoes
The previously described volcanic centers are primarily silicic eruptions, though sulfur and SO2 are most certainly involved. There are numerous other sites with varying levels of sulfur or SO2 eruptions. If we use SO2 as a water analog on Io, perhaps the primary sulfur eruption sites are more properly compared to hydrothermal systems at and near earth volcanic centers.
Tupan Patera is one of the most colorful volcanic centers. It is 75 x 50 km. It looks like it has an active lava lake that overturns quietly like Loki.
Culann Patera has both silicate and sulfur volcanism. It is also highly colored and appears to have lava tubes. It is a persistent thermal source that may indicate yet another lava lake that quietly overturns.
Emakong Patera and dark channel flow to the east. Patera is off the mosaic to the west (left). Dark channel is a crusted over braided channel that may convert to a lava tube as it travels east. NASA JPL mosaic courtesy Gish Bar Times
Zamama was one of the first hot spots detected by Galileo. It has low shield volcanoes and primary lava flow field over 140 km long. Newer flows appear to be emplaced on top of the existing flow field.
Emakong Patera is 75 – 65 km and appears to be the location of extensive sulfur volcanism. It also has a lava lake with a ring around it, much like benches on earthbound lava lakes.
Balder and Ababinili Paterae have very bright floors, with an abundance of SO2 coverage. This is thought to be due to SO2 eruptions.
Keck telescope thermal image of Surt eruption in 2001. Most thermally powerful eruption detected so far on Io. Image courtesy NASA JPL via Ashley Davies
Final interesting feature are the plumes at Surt and Thor. The 2002 eruption at Surt was the largest thermal emission detected on Io. It was first discovered by the Keck telescope and almost doubled Io’s thermal emission for a while, classifying it as an outburst eruption. Thor erupted the tallest plume observed on Io at over 500 km in 2001. It erupted lava flows and laid down a white SO2 ring around the patera.
Annotated image of Io showing major eruptive centers. NASA JPL image via the Planetary Society
Eruptions and Plumes
Eruption style in patera are either lava lakes of flows across the surface. These eruptions can be as large as lava eruptions spreading across the plains. Lava lakes appear to be directly connected to a magma source below and are typically covered with a thin crust. These crusts overturn from time to time, with the colder, heavier crust foundering and sinking. This typically increases infrared (IR) signature of the lake until a new crust forms.
Flow dominated eruptions are called Promethian volcanism. These are extensive and are a major terrain type on Io. Magma is erupted from either floors or edges of patera or from surface fissures. The flows are similar to what we see in Hawaiian volcanism, with flow rates holding relatively steady for an extended period of time (years to decades). Individual flow thicknesses are thought to be around a meter, though layering of multiple flows has built substantial structures whose total thickness are unknown. Active flow fields more than 300 km long have been observed. IR signature of these flow fields indicates that there are active lava tubes from the source vent to the breakout of new magma at the edge of a field. There is a known inactive field measuring over 125,000 km2.
Tvashtar Patera in eruption. Galileo images taken 1999 and 2000. Shows mostly effusive eruption with some plume deposits. Image courtesy NASA JPL via Anne’s Astronomy
The final type of eruptions on Io are explosive or Pillanian volcanism. There are two types of these. The first is due to interaction of hot magma with SO2 snow / ices on the surface. The second is an old fashioned Plinian / super-Plinian plume complete with pyroclastic flows. These are also called outburst eruptions, are typically short duration (weeks to months), have large volume ejection rates, and are visible from earth due to significant infrared (IR) emissions. A typical eruption starts with a fissure and extensive lava fountains. Outburst fountains at Tvashtar in 1999 and 2007 produced a 25 km long, 1 km tall curtain above the surface.
Explosion-dominated eruptions can also produce large volumes of lavas. They generally last longer than the lava fountains, at weeks to months as compared with the fountains at a few days to a week. A 1997 eruption at Pillan Patera produced over 31 km3 over a few months. Its lava flows were ten times the thickness of the typical Io flow at an estimated 10 m thick. Flow rates are similar to those at Iceland’s Loki in 1783.
Voyager 1979 image of Io showing active vent a Loki and massive plume out of Pele. Image courtesy NASA JPL via Volcano Secrets blog
Explosive eruptions will also produce large pyroclastic and plume deposits. The 1997 Pillan eruption covered 400 km2 of dark silicate materials and bright sulphur dioxide snow. Two eruptions from Tvastar in 2000 and 2007 generated 330 km tall plumes.
Volcanic plumes are relatively uncommon, though appear to be the major player in resurfacing Io and erasing its cratering record. At least 20 active plumes were observed by Voyager and Galileo.
The most common of these are Prometheus-type dust plumes that are created when lava flows vaporize underlying SO2 frost and snow. These are typically less than 100 km high with eruption velocities less than 0.5 km/sec. Dust plumes like this generally have an umbrella-like appearance. These are frequently seen at flow-dominated eruptions. Many of these have an outer halo of gas rich material reaching heights of the larger plumes.
Overhead image of Prometheus showing prominent 2004 plume. Image courtesy NASA JPL via thunderbolts.info blog
The most vigorous plumes are Pele-type eruptions, with significant sulfur and SO2 involvement from the vent itself. They carry silicate pyroclastic material with them and are usually associated with explosion dominated eruptions. The exception to this is Pele, which the plume sources from a long-lived lava lake eruption. They have higher vent temperatures and pressures, generate plume velocities up to 1 km/sec, and reach altitudes of 300 – 500 km above the surface. There is little dust at altitude, making them somewhat difficult to observe.
Just to make sure things are interesting, some plumes do not fit neatly into the Prometheus or Pele types. One example would be a pair of Loki plumes observed by the Voyagers, classified as a hybrid of the two types.
Schematic of possible internal structure of Io. Image courtesy OSU Volcano World
Tectonics
The tidal interaction of the four moons with each other and Jupiter is sufficient to maintain liquid oceans. However, the tidal forces drop with distance from Jupiter, so none of the other moons have active volcanoes. The next moon out, Europa has a kilometers thick ice cover on an ocean that may be 100 km deep. The third and largest moon, Ganymede is thought to have several oceans interlayered with ice and rock. Calisto, the fourth Galilean moon may not have any oceans at all. As it is not in a strong resonance with the other moons, it is the least dense of the four moons. It is made up of a mix of rock and ice that have not differentiated much during its lifetime.
There is no consensus on the thickness of Io’s crust, though at least 30 km is needed to support 18 km tall mountains. Io’s magma is even more difficult to figure out. If the current level of activity has been constant through the lifetime of the solar system, the entire silicate crust would have undergone hundreds of episodes of partial melting. This would eventually yield high silica content, viscous magmas, of relatively low melting point and density.
Another possible view of Io internal structure. This one depicts a magma sea underlying the crust offset due to tidal locking with Jupiter. There are similar theories about the earth’s moon (minus the magma sea). Image courtesy Battaglia et al
Yet we see low viscosity magmas on a global scale. This may mean a highly efficient recycling process or delamination of buried lithosphere by a vigorous mantle convection. Another possibility is that Io’s tidal heating is cyclic, and it goes through extended periods of quiet followed by a period of intense heat buildup, formation of a global magma ocean, and widespread intense volcanic activity until the heat is dissipated.
Galileo merged color mosaic of the entire moon. Image courtesy USGS
Conclusions
Like most bodies in the solar system, the more we look at Io, the more we figure out that we don’t know. For instance, the actual location of volcanoes does not agree with predictions where they should be. We don’t have a good idea yet where all the magma comes from. Subsurface magma ocean? Crystal mush in the asthenosphere? Why does SO2 behave much like water does on earth with snow and what appears to be an aquifer layer just under the surface? Although there are a few shields and cones visible, most activity is related to patera. What causes the patera? Better yet, what locates them? Happily, we have figured out how to observe Io from afar and can at least see large outbursts. The Davies book has two pages of great questions pp 292 – 293.
There is an Io orbiter in the planning stages for a return to the Jovian system. When and if it flies is anyone’s guess. I find it fascinating that silicic volcanism halfway across the solar system can be used to model what goes on here on earth.
Galileo image of Io. Pele is in the lower left of the image. No active plumes visible on the limbs. Pele plume deposits clearly visible as is activity a Pillan. Image courtesy NASA JPL via Space News
Additional Information
https://physicstoday.scitation.org/doi/full/10.1063/1.3027996
http://www.planetary.org/blogs/guest-blogs/2014/0812-three-major-volcanic-eruptions-on-io.html
https://physicstoday.scitation.org/doi/full/10.1063/1.3027996
http://www.planetary.org/blogs/guest-blogs/2014/0812-three-major-volcanic-eruptions-on-io.html
https://www.wired.com/2014/03/eruptions-captured-on-io-and-venus/
http://spaceref.com/jupiter/sodium-not-heat-reveals-volcanic-activity-on-jupiters-moon-io.html
https://www.solarsystemquick.com/io.htm
https://authors.library.caltech.edu/86237/
https://www.researchgate.net/publication/249558345_Volcanic_activity_on_Io_during_the_Galileo_era
https://geology.com/articles/active-volcanoes-solar-system.shtml
https://www.space.com/16419-io-facts-about-jupiters-volcanic-moon.html
https://www.space.com/30530-jupiter-moon-io-magma-volcano-mystery.html
https://www.space.com/36452-auroras-from-io-reveal-mysterious-interior.html
https://en.wikipedia.org/wiki/Volcanology_of_Io
https://arxiv.org/ftp/arxiv/papers/1211/1211.2554.pdf
http://lasp.colorado.edu/home/mop/files/2015/08/jupiter_ch23-1.pdf
https://pirlwww.lpl.arizona.edu/~jani/radebaugh-peleio-icarus04.pdf
agimarc
Spica
Granyia
volcanohotspot.wordpress.com 
Wow, A. amazingly researched article. Breathtaking. Well done.
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guess I should have logged in before posting that.
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Looks like a smallish eruption at Semisopochnoi last night. Measured tremor. It is currently dark with a cloud deck at 10,000′ so no visual yet. Alert level raised to Orange. Cheers –
https://www.avo.alaska.edu/activity/report_getter.php?need=current&id=378481&type=3
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Avachinsky is waking up – !
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Here are the webcams on FEB RAS, it’s cloudy now, though, and daylight.
http://geoportal.kscnet.ru/volcanoes/volc.php?ln=vid&name=Avachinsky
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White Island – NZ – Eruption!
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Alert Level 4. Moderate eruption, yes, but it has killed two of the webcams. 😦
https://www.geonet.org.nz/volcano/whiteisland
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And there were 19 people on it… seems it doesn’t look good. 😦
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At least 5 dead. 23 brought off the island. There was a group walking across the crater shortly before it went off. Initial report was 100 on the island when it went. That estimate is down to around 50, half of whom are off the island. Very, very sad. Regards –
https://www.thesun.co.uk/news/10511437/new-zealand-eruption-five-dead-two-brits-white-island/
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Got a rebuke from GVP for tweeting the eruption seismogram and saying that the tour operators, even though they are not experts, still could have seen the sharp changes in restlessness of the volcano and decide for themselves not to ship people over.
Was told, I am cherry-picking on one set of data and, as a non-expert, I should leave the analysis to experts.
Have I done an analysis? I have been seeing these seismograms almost daily for the last ten years, and so probably have the tour operators. That’s what I think, and probably not just me.
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I would think the experts in the field are in much the same position as Boeing engineers are with the 737 Max, having to address what they have done (or didn’t do) in the aftermath of a tragedy that at some level involved their expertise.
Very easy to tell people to butt out of the discussion. Not nearly as easy to do a data dump and let others make up their own minds. When you tell your fans and supporters to sit down and shut up, it is difficult for them to help you get a good picture of what actually took place out there in public. Remember that you and I both caught the satellite vent that shortly preceded the Krakatau flank collapse.
Even harder when lawyers and lawsuits are going to be involved. As there are multiple dead people and a few dozen more with terrible burns and medical care necessary to treat them for a years to come, there are going to be a LOT of lawyers shortly involved. And the bureaucratic response to that is generally to hunker down in the bunker and hope to weather the impending storm.
There was at least one news report yesterday that described the volcano as too dangerous for volcanologists to visit. I have not verified that either way, and ascribe it as a wild haired claim that is not uncommon in the Fog of War following a tragedy when the wildest rumors are flying early and often.
We are fans and amateurs, trying to learn this subject to the best of our ability. We generally stay in our selected lane. We address our deficiencies early, often, and most importantly publicly, posting corrections and explanations when necessary, bringing our readership thru our learning journey with us. We are trying to get better at what we do without being inflammatory. In short, we are trying to help. Cheers –
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Hi guys, am in NZ at the moment and visited White Island about ten years ago. First thing to remember is that everyone who goes on a tour there is informed of the risk that an eruption could happen at any time. You also have to sign a paper saying you are willing to take the risk. Secondly, we all know that in the majority of cases of heightened activity nothing happens and the volcano goes back to sleep. IMO geonet did well to raise the alert level to 2 several weeks beforehand. Tour operators have still been taking trips there at Level 2 for years. They also know that volcanos are by nature fickle and that something could happen at any time with little or no warning.
It’s a difficult thing to weigh up. I feel very sorry for those that lost their life.. and even more sorry for those now critically burnt and recovering.
When it comes down to it, something like this was very likely to happen sooner or later. But does that justify making the volcano off limits? It’s a hard call. People will always take risks. Main thing is keeping them informed and let them decide for themselves.
In my view there are good arguments for banning children from the trips and perhaps limiting the number of people on the volcano at any one time to 20 or so. But I wouldn’t ban it completely unless unrest was very significant.
At the time of writing, it looks like the phreatomagmatic burp that turned out so tragic might just be the first stage of a larger eruptive phase as tremor is now as high as it has been since 2016, so talks of future tours may anyway be redundant. And yes, the volcano is off limits to anyone at the moment, including volcanologists. They have enough remote sensors that are still working.
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https://www.geonet.org.nz/volcano/monitoring/whiteisland
RSAM and SSAM both sharply elevated today after a short hiatus after the eruption. Looks like something bigger is coming to me.
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>Main thing is keeping them informed and let them decide for themselves.<
That's what I was aiming at, in regard of the tour operators. They have all information they need. They can decide ad hoc to suspend tours if the situation has changed (and it HAD changed, already on Saturday).
Of course visitors can take it or leave it, but they know still less about the risk than the company. And what about the tour guides? I believe they can not just refuse to go.
Wish you a great time there anyway!
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I was thinking about a post on White Island until I ran across the following at WUWT this morning. Pretty comprehensive. Might do one anyway. We’ll see. Cheers –
https://wattsupwiththat.com/2019/12/11/when-volcanoes-attack-white-island/
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good article and interesting commentary. The only problem I have is that there are potentially far far worse volcano-related dangers out there. Taal, Campi Flegrii, etc. where it is also only a matter of time before a major event happens. Where do you draw the line for an “acceptable” level of risk? I am currently in Auckland. Out the window I have a direct line of sight to Rangitoto, 4 km away to the crater. A maar crater is just up the road. Sooner or later there will be another event in Auckland and by the latest accounts, the city might only get 5 days warning or even less before an eruption. But even that risk pales compared to a major earthquake, which gives you no warning at all.
Like White Island, Ruapehu is also known for its phreatic explosions. I doubt many people are in favor of making the mountain out of bounds, though, like White Island, a case could be made for a permanent exclusion zone in direct proximity of the crater.
In retrospect, and something I also wondered at the time when I visited White Island, was if it would not be wiser to view the crater from its western wall. The problem with that option is that the wall is also instable, hard to access and offers no sheltered bay for disembarking. It would however, protect most tourists from a sudden phreatic blast, which all get directed eastwards due to the topography.
Again, this disaster was just waiting to happen to somebody, sooner or later.. But, from an individual’s perspective it is still a case of massive bad luck. In the vast majority of visits you would come away unscathed. Sorry if that sounds callous. But I don’t buy the argument that the tourists were not suitably informed. The very attraction of the place is that it is the jaws of hell and such things can happen at no warning.
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Thanks Bruce. Great perspective. I can’t recall of a maar formation near anything inhabited in recent memory. Auckland might just (sadly) demonstrate that happening.
We are a year out from our M7.1. I understand the lack of earthquake warning completely.
Like you, I appreciate risk taking. If we can’t have choices, even to do dangerous stuff that we know is dangerous, what good are we? Adopt your previous suggestions for no kids and to limit the overall number of island visitors so as not to overwhelm the rescue people for a nice opening bid.
Would be interested in your suggested approach to the crater from the western slope. Given the unexpected eruption, that solution might be more desirable in the not so distant future.
Your comments aren’t callous at all. Rather, they are guts ball, suggested best ways to address a dangerous system by people ready, willing and able to enter a physically dangerous locale. Cheers –
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Starting from the left edge again.
The thing that bothers me about W.I. is NOT that it is open to the public. It is that people are taken there by a booked trip.
Everyone who books a trip, a cruise, a flight etc. trusts the company that it takes care of the safety of their passengers. They trust the company to cancel the journey/flight if something is amiss. They will still trust when they have had to sign a waiver. As the company is sending their own guides with them, what could go wrong?
If visitors were to organise their own boat ride, offered perhaps by local boat owners, the majority would think twice or three times before they go. They would have to take responsibility for themselves, their family. Not trust a company that things will be fine as long as the scheduled boats are going out.
I mean, all dangerous volcanoes in the world are open for everybody to go whenever they feel adventurous. It’s a great difference though if a company says, everything is great, we are going as planned.
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Hi Granyia,
I understand what you mean and there is an uncomfortable marriage here of people running a business and putting their customers at risk in doing so. A conflict of interest appears hard to avoid. That said, like in any business, the operators don’t actually want anything to go wrong to anyone. The feeling I had when I visited it was that the guides were very familiar with the place and also aware of the risks. They of all people have the highest exposure as they are frequently at the crater, yet all of them were passionate about their job. The tourists are there for a maximum of about an hour, if I recall correctly. If a tourist operation were to go for a zero risk approach, you would have to limit it to helicopter flights (also not without a certain risk). The fact of the matter is that there is always some kind of risk involved, even when you get in a taxi or on a cruise ship. It might be negligible in the grand scheme of things, but there is no such thing as a risk-free tour.
The other issue is, given the rise to Alert level 2 and the signals documented by Geonet, shouldn’t some kind of threshold have been passed? Well, sure, somewhere there has to be a threshold. But a phreatic eruption of this nature can also occur without any warning even at level 1 – witness the Te Mari eruption at Tongariro a couple of years ago. Geonet also states this explicitly on its website. And White Island has frequently been at level 2 and simmered down again. I don’t think the question here is one of principle, but one of degree. Given that you can’t rule out the risk and informed tourists are willing to take the risk, when do you say, sorry, the risk level is too high? I imagine this would be when the guides themselves don’t have a good feeling. Unfortunately, this stage hadn’t been reached before it erupted. The scale could also have been quite different. A small steam explosion in the crater might have occurred without injuring anyone.
Finally, the response by the operators including helicopter operators who were off duty and had no tourists on the island was nothing short of heroic, flying out immediately after the eruption and rescuing all they could. A cynic might say that is the least they could do, after earning their living from the place. I don’t think that is warranted. Of the operators I met, all were genuine people, aware of the risks, but still willing to take it for an experience of a lifetime. And that is also how they approached their clients.
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Think of it in terms of booked fishing trips. The good news is that there are LOT of guides and boats that have been doing this for a long time, carrying everyone from infants to 90-year olds all with varying levels of experience. The bad news is that the water is for the most part, very cold, with times of useful consciousness measured in minutes (around 0+30 at 4 C), as a result we lose people every summer, particularly those not wearing life jackets. Boats burn. Some sink. Sometimes people go for swims in the Big Water of the North Pacific and have to wait a while. Not intended to be a life threatening activity. Unfortunately sometimes it is. It is all about acceptable risk.
Another story: When I was in the flying business, we buried someone I knew and went out drinking with at least once a year. Did that all 13 years I flew. Came to hate funerals. Tried to do it to myself 3 times I knew of, mostly due to inattention. God had other plans for me. I knew and accepted the risk. My folks, not so much, and didn’t like me in that business at all.
We take risk. Some more than others. Sometimes we get unlucky. The trick is never to get yourself in the position of needing good luck to come back from your outing. Still very, very sad. Cheers –
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I’m a bit worried about the police now talking of doing a quick mission to collect the bodies. The problem is primarily the dithering. The helicopter pilots from the tour operators who flew out on instinct after the first blast probably had the best chance to do it, acting on the premise, that the system had blown and would need a little while to recharge. Unfortunately, they were prohibited from finishing the job in this little window of opportunity. Now, after all the dithering and red tape, the system is getting increasingly fragile, particularly if you see the RSAM chart. My feeling is that the police have missed their slot. Going now could lead to another tragedy.
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Just to add to the fun, Shishaldin blew this morning putting a plume 8-9 km around 0710 L. The plume is drifting W – NW at 45 kts. Both it and Semisopchonoi are both listed as Color Code Orange and Alert Level Watch. Cheers –
https://www.avo.alaska.edu/activity/report_getter.php?need=current&id=379941&type=3
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Thank you both for your insights, I keep thinking about the problem too.
But for now, we have a new post! 🙂
https://volcanohotspot.wordpress.com/2019/12/12/sent-ash-around-the-world-volcan-ceboruco-mexico/
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@ Granyia… another point to consider is NZ’s somewhat unique policy on operator liability:
https://www.theguardian.com/world/2019/dec/12/white-island-volcano-victims-cannot-bring-civil-lawsuits-for-negligence
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Aww, this explains a lot, and actually is a terribly dangerous thing. So, any tour operators, or any company at all, can give a darn f$§k for safety measures and get officially away with it, covered by the state? Who would agree to a law like that? I mean, it costs the state… perhaps millions in treatment costs, and supports unsafe work environments, apart from tourists.
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Well, on the one hand sure. But that was not the intention behind ACC when it was first drafted into law. The main intention was to sideline the legal industry and avoid the inflated liability settlements common in the United States. At this it is effective.
Yet operators do have to meet safety standards or they will lose their license. They can also be found criminally liable and end up in jail. Also it’s not too good for business when you kill off your customers, so they have a vested interest in keeping things operating at a high safety level.
There will no doubt be a reassessment of White Island. Possibly even the ACC will tell the government the cost of this rescue mission and hospital treatment was so astronomically high, the island will have to be ruled out of bounds.
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