The New Decade Volcano Program No. 1 – Ioto, Japan

As we raise the flag for Ioto, formerly known as Iwo Jima, we cannot fail to mention “Raising the Flag on Iwo Jima”, the historic photograph taken on February 23, 1945, by Joe Rosenthal. It was a re-enactment, it does not represent the actual moment the island was captured earlier the same day and wasn’t even the first “Star Spangled Banner” to be flown at the mountain summit.

As we raise the flag for Ioto, formerly known as Iwo Jima, we cannot fail to mention “Raising the Flag on Iwo Jima”, the historic photograph taken on February 23, 1945, by Joe Rosenthal. It was a re-enactment, it does not represent the actual moment the island was captured earlier the same day and wasn’t even the first “Star Spangled Banner” to be flown at the mountain summit.

A recurrent theme throughout this series has been the unknown and understudied which with our current understanding of geology and volcanology could pose a danger to millions of people. From the water-enriched and thus highly explosive magmas of Kelut to Aso, the problems of a giant edifice such as Mayon, the understudied Taal and Bali volcanoes, the inexplicable volcanism of the Cameroon Volcanic Belt (Mt Fako/Mt Cameroon), the unusual geological setting and complexity of the Trans-Mexico Volcanic Belt and the threat posed by even moderately large eruptions such as at Campi Flegrei and Apoyeque, there is one major threat that we have not yet looked into: the one posed by a submarine “supervolcano”.

Some of the most destructive and disruptive eruptions in human history have been from volcanic islands where the collapse of the edifice has allowed water to come into contact with the upper magma chamber, something that has compounded the magnitude of the eruptions manifold. The 1883 eruption of Krakatoa is something of a household name even amongst people not interested in volcanology, films have been made about it. The ~1650 BCE eruption of Thera is an even better example. Not only did it all but wipe out the Minoan civilization and not only has it been linked to Biblical events in Exodus. It has left indelible imprints in almost all of our European languages such as the adjectives “terrible” and “terrific”, not to mention the prefix “tera” as in terawatts, teraton etc. Yet neither Thera nor Krakatoa are representatives of the very worst possible scenario, one where barely subaerial or wholly submarine volcanic eruptions are concerned. There actually are very large submarine volcanoes in many places around the world, submarine volcanoes capable of a VEI 7 “supereruption” and our choice for #1 in this series is such a volcano. This volcano has shown an enormous amount of inflation over the past 1,000 years and is the strongest candidate that we are aware of for a future VEI 7 eruption. It threatens several of the most densely populated as well as some of the most developed areas of the World. Its name is Ioto, Sulphur Island, formerly known as Iwo-Jima.

Aerial view of Mount Ioto from the SW with the 167 metres high Suribachiyama, the island’s highest peak. (WikiMedia Commons)

Aerial view of Mount Ioto from the SW with the 167 metres high Suribachiyama, the island’s highest peak. (WikiMedia Commons)

The main problem of submarine volcanoes are that they for obvious reasons are neither well-studied nor easily monitored. Thus our knowledge of them as compared with volcanoes such as Etna, Vesuvius or Mt Fuji is rudimentary. Hence, there is little or no information available. Consequently, any article on such a volcano will have to be highly conjectural. This is one of the reasons why we have chosen to present this article in the form of a work of fiction. The other is that if our conjectures should be correct, or even in the adjacent ballpark, the potential death count is staggering and the consequences for civilization as we know it dire. The threat from Ioto however is real and this story is based on published literature.

Just a few facts before we go into the story. Uplift at Ioto is the greatest known as far as we are aware of with an annual average uplift quoted as 0.25 m per year over the past 500 years. The beach where the surveyors of Captain James Cook landed in 1776 now lies more than 40 metres above sea level. The WW II landing beaches are 17 m above present sea level. As with all volcanic uplift, the actual volume intruded is twice the surface expression which gives minimum figures of 250 m over the past 500 years, >80 m over the last 239 years and 40 m in the past 71 years alone. The actual size of the magmatic intrusion depends on the horizontal extent of the body into which it intrudes. Even if we accept not two but just the one of the proposed sill structures with a side (=diameter?) of 5 km directly below Ioto, we arrive at a figure of at least 5 km3 over the last 500 years and no less than 0.7 km3 since 1944 alone – and these are very much minimum figures. With such a copious inflow of fresh magma, the question is not if Ioto will have a major eruption but when.

As you read, please remember that this is a work of fiction and that many of the interpretations of the scientific data presented are dramatised for effect and not necessarily accurate.


The knocking on the door would not go away. In his dream, Chris Schofield had just taken his seat on the KLM/Air France flight from Fukuoka to Amsterdam he was scheduled to board tomorrow morning at 11:05, Japan time. The flight would take just over twelve hours and after touching down at 15:25 CET, he had to take a connecting flight on to Manchester. All in all, it would take him more than eighteen hours and by the time he got home, he would be jet-lagged dog tired. He managed to open his eyes to cast a glance at the red LED display. 03:41 A.M. “Ohhgod, nooo! Go away!” He really did need his sleep this morning.

“Dr Schofield? Chris! Please wake up! It’s me, Toru. Toru Hiryoki.” The insistent knocking would not stop.

Dr Torunasuke Hiryoki was his JMA host, Japan Meteorological Agency, the authority responsible for amongst other things volcanic monitoring and hazard mitigation. At one point, there had been concern that Aso was about to have a major eruption and Chris had been detached from his post at Manchester University in order to follow events on location. In the end, Aso hadn’t done anything too spectacular, unless one counts a seven-weeks long outburst of mainly Strombolian to Vulcanian explosions, totalling not much more than a VEI 2, as such. It was just another deep intrusion of fresh magma, substantially larger than preceding ones, true, but nowhere near large enough to cause a major eruption.

Soon after his arrival in Japan a couple of months ago, before the eruptions had begun, Chris had proposed a model based on then current data that in the end had turned out to be pretty close to what had actually transpired. The models used by his JMA hosts had predicted a much larger event, possibly even including the collapse of the central portion of the caldera.

As a scientist, Chris was somewhat controversial because where others interpreted available data very much within the generally accepted model or models, he was not afraid to go out on a limb. Where others saw business as usual, he was inclined to point out and emphasise the danger signs. Where others were alarmed at the potential for disaster, he would calmly point out the reasons why disaster was unlikely. When the crisis at Aso was in its early stages, he had told Toru Hiryoki that long-term, he was more concerned by Aira Caldera because uplift continued in spite of the safety valve that Sakurajima volcano constituted being fully open since the early 1950s.

He swung his legs over the edge of the bed and stumbled over to the door. As he opened it, he was greeted by the smell of coffee that reminded him of the link between intelligence and early morning activities.

“Come in Toru, excuse me for a moment.” He motioned his friend inside and made a grab for the proffered cup before disappearing into the bathroom.

When he returned, cup gratefully held in hand and by now half-empty, Dr Hiryoki had seated himself and taken out a small stack of papers from a portfolio.

“Chris, I doubt you will have seen these before but will you please read them and give me your impressions? They are somewhat on a need-to-know basis and it has been decided that you have that need.” As he handed the papers over, Chris saw that they were scientific papers on Ioto, Sulphur Island, better known as Iwo Jima. He took a quick look at Hiryoki whose face held that inscrutable look cultivated by the Japanese not to give away any information at all. If he had still been in the least groggy from being woken in the middle of the night, not even the strongest Kopi Luwak could have been more effective. Adopting the same attitude, Chris was now fully awake. He grabbed the stack and began to read:

Fig. 1. (a) Map showing the location of Iwo-jima. (b) Bathymetric map of Iwo-jima area. The dotted circle indicates the caldera rim. The plate boundary map is inset, where EU, PA and PH indicate the Eurasian, the Pacific and the Philippine Sea plate, respectively. (Ukawa et. al. 2006)

Fig. 1. (a) Map showing the location of Iwo-jima. (b) Bathymetric map of Iwo-jima area. The dotted circle indicates the caldera rim. The plate boundary map is inset, where EU, PA and PH indicate the Eurasian, the Pacific and the Philippine Sea plate, respectively. (Ukawa et. al. 2006)

Iwo-jima is a small volcanic island belonging to the Izu–Ogasawara island arc located 1250 km south of Tokyo, related to the subduction of the Pacific plate underneath the Philippine Sea plate (Fig. 1). The bulk of the island is located within a mostly submarine caldera… …An extremely high uplift rate (averaging 0.25 m/a over several hundred years) characterizes the volcanic activity of Iwo-jima. This deformation is believed to be due to post caldera uplift… … leveling and trilateration surveys from 1976 to 1995, and GPS surveys from 1996 to 2002. These observations have detected two patterns of continuous crustal deformation: concentric subsidence around Motoyama at the center of the Iwo-jima caldera and uplift surrounding the subsiding area… …The best-fitting subsidence source geometries for 1998–2000 and 2000–2002 are horizontal, squared-shaped sills with side lengths of 4 and 5 km, respectively……the continuous subsidence and uplift may be explained by movement of volcanic fluids (probably geothermal) to balance the vertical load of the volcano, while the episodic uplift appears to be related to magmatic unrest.

At this point, there was the sound of several cars driving up outside the hotel, stopping to disgorge their occupants. There was what sounded like orders given and a stamp of feet. Chris looked up from his reading and raised an eyebrow inquiringly.

“The police. A helicopter has been dispatched to take us to Tokyo. Please Chris, there is not much time.” The implications hit Chris like sledgehammer blows. There was a volcanic crisis at Ioto. For some weird reason, his opinion was sought. For a brief moment, the child’s impatience to know struggled with the scientist within. Then he returned to his reading:

The Iwo-jima volcano is a large stratovolcano The bathymetric topography indicates that the volcanic edifice is 40 km in diameter at the sea bottom with a caldera rim of about 10 km at the top. Iwo-jima island is small, 8 km long and 4 km across, and the main part of the island is located within the submarine caldera. The island is divided into three topographical areas: Motoyama, Suribachiyama, and Chidorigahara. Motoyama is a post caldera, shield-shaped, central cone, with its highest terrace 100 to 120 m above sea level. Suribachiyama, the island’s highest peak (167 m), is a scoria cone with lava flows located on the caldera rim. (Kamaiwa is also close to or on the caldera rim.) Chidorigahara is a sandy isthmus located between Motoyama and Suribachiyama.

Fig. 2. Map showing the location of benchmarks and volcanic activity since 1889. The [phreatic] eruption sites since 1889 are indicated by star symbols. The interval of topographic contour lines is 50 m. (Ukawa et. al. 2006)

Fig. 2. Map showing the location of benchmarks and volcanic activity since 1889. The [phreatic] eruption sites since 1889 are indicated by star symbols. The interval of topographic contour lines is 50 m. (Ukawa et. al. 2006)

Following the first recorded activity in 1889, a total of 20 phreatic eruptions, mostly small steam explosions, have been reported… …Geothermal activity in Iwo-jima is very high and the rate of total heat discharge was estimated to be an order of 108 cal/s . On the island many active fumaroles occur, and the temperature of the fumarolic gas ranges from 100 to 128 C… …Volcanic rocks from Iwo-jima are trachyandesite with a SiO2 content of 54% to 58%. Although the topographical structure of Iwo-jima suggests a large caldera-forming eruption (similar to Crater Lake, in Oregon), no clear evidence of a large eruption has been found mainly because of the island’s remote location. Thick pumiceous tuffs overlying glassy lava cover the Motoyama area. 14C ages from charcoal associated with the tuffs give ages of 2700–2800 BP, suggesting that the caldera-forming eruption occurred no earlier than that time, and that the uplift represents post caldera deformation… … A comparison between survey measurements and aerial photographs taken in 1952 and 1968 demonstrates that the coastline on the north to northeast part of the island was uplifted about 9 m during this interval, an uplift rate of more than 0.5 m/a. Overall the uplift was highest along the coasts and lowest at the center of the island with maximum uplift (9 m) around the northern coast and minimum uplift (5 m) near Motoyama. During this same period, Suribachiyama was deforming at a slower rate (1 to 3 m of uplift).

“They construe an uplift of 1 – 3 metres as evidence of subsidence? Because it is less than the 9 metres observed elsewhere? But…?” He leafed through to the several pages of maps showing uplift and lateral movements. “This does not fit! With one or two exceptions these maps clearly show that the centre of uplift lies to the NW of Ioto. Look!” He pointed to the maps. “Uplift is almost always highest in the NW, substantially greater than in the SE. And this is accompanied by a lateral motion towards the SE!”

Hiryoki remained as inscrutable as ever and made no reply. As Chris bent back to his reading, he got up and walked to the door in response to footsteps heard approaching from the corridor. He opened it to let in the JDF MP detail. Out of respect for Chris, their conversation was in English.

“Sergeant, please see to it that Dr Schofield’s luggage is taken care of.” A short command in Japanese and the two MPs accompanying the sergeant immediately complied. Chris was mostly packed as was his habit to do the evening before travelling. After quickly adding the few items not packed, the detail went on its way, bearing Chris’ suitcases leaving his cabin luggage and jacket behind.

In the meantime, Chris had moved on to the second and third papers. They mainly repeated and bulked out the conclusions of the first; that the caldera was the result of ‘a large caldera-forming eruption similar to Crater Lake in Oregon’, but that ‘no clear evidence of a large eruption has been found mainly because of the island’s remote location.’ Chris snorted derisively. Had the Ioto caldera truly been the result of such an eruption the resulting caldera would have been far deeper and Ioto island would still most likely have been many hundreds of metres below the surface. Then a couple of microphotographs caught his attention:

Representative microphotographs showing sizes of ash particles from pyroclastic deposit. a: Motoyama pyroclastic deposit. b: Stratified tuffaceous deposit of Suribachiyama upper pyroclastic deposit. Samples were passed through a sieve with 125 um holes. (Nagai & Kobayashi, 2014)

Representative microphotographs showing sizes of ash particles from pyroclastic deposit. a: Motoyama pyroclastic deposit. b: Stratified tuffaceous deposit of Suribachiyama upper pyroclastic deposit. Samples were passed through a sieve with 125 um holes. (Nagai & Kobayashi, 2014)

“Proof! Look, Toru!” He pointed to the photographs. “If there really had been a caldera-forming eruption such as Crater Lake, there would not have remained a magma chamber capable of holding such large, well formed crystals that these are fragments of. Let alone erupting them so peacefully centuries later. It is still there, that eruption could still happen”. Chris was referring to the “similar to Crater Lake” eruption invoked by the first paper. In the background, they could hear a helicopter approaching, the sound growing to a thunder as the pilot skilfully set it down at the edge of the hotel parking lot. The MPs were back to escort them. Hiryoki took possession of the papers while Chris hastily grabbed his jacket and shoulder bag.

As they settled down in the rear compartment, an MP helped Chris and Hiryoki with their helmets. When the MP gave the thumbs-up and closed the door, the civilian who had waited for them spoke up over the intercom.

“Good morning Dr Schofield! My profound and sincere apologies for dragging you away like this but as you may have surmised there is a crisis that requires your particular skills.” He introduced himself as Hiroshoi Yamamoto, secretary to the Minister of Internal Affairs and Communications and yes, he had the honour of being a distant relative of the great Admiral.

“This is a secure line, Dr Schofield. I take it that you have read through the papers given to you by Dr Hiryoki. Please? What are your initial impressions?”

“I’ve only had a quick read-through of the relevant papers and my first impression is that the original researchers may have come to a possibly erroneous conclusion and that subsequent research has committed the error of trying to make the data fit a flawed model”.

“This is part of Japanese culture, I’m afraid. You do not tell a superior that he is wrong. That is for the superior to realise and amend.”

“Not so much a Japanese as a human failing, Mr Yamamoto! It’s ubiquitous. In science, we talk about paradigms and we tend to limit our quest to that for a truth comfortably within the established paradigm. Especially if we are junior researchers.”

“Well Dr Schofield, what then is your outside-paradigm evaluation please? And don’t worry about using technical language. I took a basic course in geology at university and the JMA has, as you may have surmised, kept me filled in with recent developments.”

“That their interpretation of the exceptionally high inflation of Ioto represents the post-caldera movements of a horst or a resurgent dome. Contrary to their interpretation, I find evidence that the main magma chamber of Ioto could not have been destroyed in the 2.7 kA event. At best, it was only partially damaged.”

“And how does that explain the findings of Dr Ume Kiwasawa and her co-workers?”

“They may be partially correct. Do you recall the 2010 eruption of that Icelandic volcano with the unpronounceable name? Well, it began with a flank eruption but then there was a larger quake and the channel was blocked. Two weeks after that the main crater erupted. I believe that something similar can be applied to Ioto.” He then related his interpretation of the GPS data and the proof provided by the microphotographs that the main magma chamber of Ioto was still there and how its presence could explain all the data. Secretary Yamamoto listened, then nodded to Dr Hiryoki who held up a couple of sheets.

“Dr Schofield, two days ago, a major earthquake swarm began below Iwo Jima. Since then the focus has migrated from 27 km depth to about 12 km as of about an hour ago. Gas emissions have increased sharply and there have been reports of minor phreatic explosions. Here is the data for this as well as a printout of the latest data for ground deformation. As you can see inflation over the past 18 hours is 1.3 metres at Kamaiwa in the northwest. And between 0.7 and 0.9 metres in the southern and eastern part of Ioto. But the lateral movement is far greater, slightly more than three metres towards the southeast. I think it’s safe to assume that the model you have just proposed is far more likely to be correct, Dr Schofield.”

Chris leaned forward to accept the print-outs. Then he studied them for a few seconds before he leant back, his eyes focussing on infinity. “Oh my God… It’s Kuwae all over.”

“Please explain Dr Schofield, what is Kuwae.” The voice of Secretary Yamamoto was absolutely calm over the headphones, as if merely shrugging off the minor inconvenience of a delayed dinner.

“Kuwae, Mr Secretary, is a submarine caldera in Vanuatu, about 3,000 km from New Zealand. It is thought to have had a VEI 7 eruption around 1452 CE that caused a tsunami powerful enough to leave palaeotsunami deposits as high as 42 metres in the far north of New Zealand. That’s basically the same as the maximum recorded height of the 2011 Tohoku disaster, at Miyako.”

“So if you are right, what do we do?”

Chris did some rapid calculations on the back of a piece of paper. “What do you do? The question is, what can you do! Look, there’s a great uncertainty with these things; whether or not they are powerful enough to cause mega-tsunamis, let alone ocean-wide ones. Kuwae says they do and if so – God help us all if I am not wrong – if so…” He swallowed hard. “Mr Secretary. Tokyo lies only some 1,250 km from Ioto. The absolute minimum height for such a wave as it reaches land is 25 metres, roughly three times that of the Tohoku tsunami and as that reached as high as 40 metres as it rolled inland…”

The location of Ioto (Iwo Jima) in relation to Tokyo, Shanghai and Luzon, Philippines as expressed in distance (km) and time at a tsunami propagation speed of 750 km per hour.

The location of Ioto (Iwo Jima) in relation to Tokyo, Shanghai and Luzon, Philippines as expressed in distance (km) and time at a tsunami propagation speed of 750 km per hour.

He put his hands to his face and tried to rub his temples, a futile gesture as the helmet covered them. Yamamoto and Hiryoki remained silent, each contemplating the implications of what Chris had just told them. Nothing more was said until they had landed on a government helipad on a Tokyo building a few minutes later.

They were immediately escorted into a small conference room and told to wait, but it was not long before a small group of men that included not only the Prime Minister of Japan but also some of the Top Brass entered. The PM had greeted them by saying that regrettably, they did not have time for proper introductions and would Dr Hiryoki please begin his presentation. Only 15 minutes later, Chris had repeated his findings to the PM who had listened attentively without interruption. When he had finished, the PM asked him how certain he was of his projection and what the implications were.

“Look, my off-the-cuff calculation gives a most-likely pre-landfall height of 40 metres, but let’s go with the minimum figure of 25 and pray that I am very, very wrong. At an open-water propagation speed of about 750 km per hour, this wave will strike Tokyo and the East coast of Japan in about an hour and forty minutes after the onset of the major eruption. By the time it hits China and the Philippines about an hour later, the wave will still be in excess of 20 metres. It will follow the Chinese coast and then simply roll up along the Huang-Ho and Yangtsee river valleys, destroying much of China’s agricultural land. Even across the Pacific, the USA and Central America can expect a tsunami wave possibly as high as four or five metres which will have severe consequences. Such a tsunami would kill not hundreds of thousands like the 2004 Indian Ocean one, but rather tens of millions.”

“But the real problem is the aftermath. Displaced survivors numbering in the hundreds of millions without food, potable water, shelter and medical aid. Infra-structure hopelessly blocked or completely destroyed. Even if help could be sent from the rest of the world, how could it get there with harbours and airports inaccessible and the routes leading from then mostly destroyed? Then all the dead bodies, animal as well as human, begin to decompose, poisoning water supplies. Without safe, potable water, how long before dysentery and other epidemics break out, killing the weakened survivors?”

The PM interrupted him by continuing. “And how to maintain law and order amidst such chaos? Will the very fabric of society survive such a disaster or will it unravel and disappear? Dr Hiryoki! As from now the senior representative of the JMA present, what is your recommendation?”

“Prime Minister, this is not a JMA matter as it is not a scientific decision. Do you or do you not inform the public? As a representative of the JMA, it is my duty to advise you of the likely or potential consequences if you do. If and when the public is informed, there will be chaos with everyone desperately trying to save themselves and their possessions. The very resources, human and materiel, needed to sustain and maintain civilised society after such a disaster are very likely to be caught up in this chaos and lost if you do so.”

As he let the implications of his words sink in, Dr Torunasuke Hiryoki glanced out of the windows where dawn had long since won its battle with night. His gaze passed over Tokyo Bay where all the vestiges of night had been banished by the rising sun, to finally rest on the horizon directly due south where they remained as he continued. “Our projections for a mega-disaster indicate that the initial death toll will be similar in both scenarios, but vastly greater afterwards if the public is informed. In the end, Prime Minister, this is a political decision.”


(Copyright rests with the author)

M. Ukawa, E. Fujita, H. Ueda, T. Kumagai, H. Nakajima, H. Morita, ”Long-term geodetic measurements of large scale deformation at Iwo-jima caldera, Japan”, Journal of Volcanology and Geothermal Research 150 (2006) 98– 118

Masashi NAGAI and Tetsuo KOBAYASHI: “Volcanic History of Ogasawara Ioto (Iwo-jima), Izu-Bonin Arc”, Japan, 2014

Taku Ozawa, Hideki Ueda, Motoo Ukawa , Shin-ichi Miyazaki, “Temporal change in crustal deformation related to volcanic activity of Iwo-jima observed by PALSAR/InSAR”, National Research Institute for Earth Science and Disaster Prevention

James Goff, Catherine Chague-Goff and Dale Dominey-Howes “Tracking the extent of the Kuwae tsunami”, Geophysical Research Abstracts Vol. 13, EGU2011-85, 2011

T. Ozawa & H. Ueda, “Research on Monitoring of Volcanic Deformation Using SAR Interferometry”, PI No 357.


217 thoughts on “The New Decade Volcano Program No. 1 – Ioto, Japan

    • And a highly prodigious magma generation system. This is the same subduction zone driving Nishinoshima.

      Much to be learned about Ito, too bad Nagoya University is expending resources feathering the cap of the government officials in El Hierro… But hey, you study what best suits your interests… and Ito going pop in a bad way would make the 2011 tsunami look like just another bad day at the track.

      Likelihood? Quite remote, but then, so are other things… 😀

      One of the needed items to form a “supervolcano” is a large supply of heat (magma) and the system under Ito seems to be doing that quite well, based on inflation…

  1. Pingback: Sulphur Island | Zoopraxiscope Too

  2. What a great way to learn, thanks Henrik. And to think they made a hit movie out of an Earthquake with implausible science. A thriller based on this information might be a good way to wake up the world to the need for real science. (and hopefully subsequent planning).

  3. Wow.. I had been wondering why there weren’t any supervolcanoes in the oceans, given the many throughs. Thanks for highlighting two of them!

    A tsunami that takes out the high-tech areas in Japan, China and California in one go will quite likely end civilisation as we know it. For one, no more new iPhones! Would it also damage the ocean cables between the Philippines and the US that connect Asia and Australia to the internet?

    • I’d guess the ocean cables would most likely suffer damage at the points where they came ashore, not on the ocean floor which will be less affected by tsunami.

  4. Chilling!!! Albert you have outdone even yourself with this article. Could the delay in presenting this somehow be tied to someone wants to make a movie based on this theme? I don’t expect and answer. 🙂

  5. Interesting article – Can’t really argue much here. Realistically, any large-scale oceanic flank collapse near a populated area would be a BIG problem, but Ioto fits the bill as a very likely candidate for a future large event.

    The Mt. Etna flank collapse event must have similary been an incredibly spectacular even in the mediterranean.

    • The Nile Delta would have had a rough day… as would the coastal Levant.

    • this is an interesting quote “University of Manchester has come up with a list of the top ten most dangerous volcanoes in the world which are in danger of erupting.”

        • Well, Albert (as quoted in the article) is based at Manchester Uni, the NDVP is VC’s take on the ten most dangerous (actually the most dangerous INSUFFICIENTLY STUDIED, but we’ll let that pass) and they are indeed ‘in danger of erupting’ at some point in the future -or they wouldn’t be on the list. Classic tabloid – individual statements are correct, but put together are misleading.

  6. Stunning article! Very well written too! Congratulations on the completion of this list. Hopefully the Mirror is the first one in a long list of many media who will propagate the awareness. Bravo and thank you!

  7. Congratulations, Henrik and Carl, on finishing this ambitious project! And it is a fitting conclusion to the series. One thing that has come out is how diverse the dangers from volcanoes are. We have seen everything here apart from volcanic gases. Tsunami risks are clearly under appreciated, including both lake tsunamis and ones in open sea.

    Since 1600, some 300,000 fatalities have been recorded directly caused by volcanoes (this list will of course not be complete, especially further into the past). Of these, probably 60-70,000 were due to tsunamis. Danger assessments tend to look only at local tsunamis and not at long-range tsunamis such as Kuwae (only recently well studied, I think) and Thera, which are far less understood. Tsunamis are assumed to be caused by pyroclastic flows hitting the water, rather than under-water explosive action. This is one are which will need much more study.

  8. Henrik, you’ve excelled yourself. Ever thought of writing fiction professionally? That was better written than some published novels I’ve seen! Better than ‘Japan Sinks’ (although perhaps that was mangled in translation). As you said, if Iwo Jima is a resurgent centre, no problem. If it isn’t, very BIG problem indeed. Makes one wonder just how many totally submarine caldera-capable volcanic systems -ie without a visible island at the surface like Ioto- there are in the western Pacific. Systems like Tavui, for example

  9. Really awesome series – I learned a lot and hardly could wait for the last few articles 😀

    A question: When compared to Uturuncu, where the magma influx is around 1 cubic meter per second – how much is it for Ioto with an uplift of 0,25 per year (0,5 in both directions)? Are the dimensions of the area of uplift known at all?

    • The area of the uplift is assumed to be the same as the size of the island. The area immediately around it is kept at 10 meter depth by wave erosion, so it it harder to know whether there is inflation there. The influx is at minimum 0.01 cubic kilometre per year, perhaps as high as 0.05 if the inflating area is twice as long. That puts the inflow as 0.3-1.5 cubic meter per second, and it has been at this rate for at least 500 years, and probably much longer. Uturuncu has a similar inflow but only for the last 20 years. Before 1992, the inflow was only 0.001 cubic kilometre per year. That seems typical: there are volcanoes which inflate faster but only for short periods. No other volcano has inflated at such a rate over such a long time. Ioto (Jima) is unique.

    • There are 31,536,000 seconds in a (calendar) year which translates to 0.0315 km^3 per year for Uturuncu. The problem with Ioto is that the lateral size/extent is unclear. The papers mention sills (plural) with sides(sic) of 5 and 4 km as a “best fit”-explanation. The estimate in the article is based on a single, circular sill with a diameter of 5 km which provides the absolute minimum sill surface area solution and for that, the annual influx comes out at 0.0098 km^3 and with the two sills of the papers just shy of 0.02 km^3 pro annum. This is clearly unreasonable.

      Why? Because with this going on for at least 2,700 years, the time given since the last (major) eruption, the sill(-s), assuming they started at zero volume, would have a height of ~1.35 km today and with dimensions of 5 x 5 x 1.35 and 4 x 4 x 1.35 km respectively not be sills but magma chambers proper. Even if magma influx did not begin until 500 years ago, another unreasonable assumption, the height – again assuming a zero-volume start – would be >250 m.

      If more reasonable assumptions are made; that the start was not made from zero volume, that the collapsed area of the invoked caldera corresponds to the size/extent of the pre-2.7 kA upper magma chamber, i.e. diameter 10 km, and that magma chamber was not destroyed, we arrive at a figure of 0.393 km^3 of magma per year for the influx.

      No matter which interpretation is correct – 0.02/a with the sills solution or 0.0393/a with a single chamber, over the past 500 years, the total influx is either 10 km^3 or 20 km^3. If that has gone on for 2,700 year since the last (major) eruption, it’s either 54 or 106 km^3 of eruptible magma. To that must be added whatever remains of the magma present 2.7 kA ago that did not erupt.

        • ok I don’t understand
          a height of ~1.35 km is clearly incorrect
          so what would be a reasonable height 100m ?

          if that’s ok then the area of the sills just goes out to
          r=5 gives 13.5 times the area

          so if r= 5 you get area = 78
          so if you want an area equalling 13.5 x 78 then divide by pi and root = radius of sills 18.37 km radius sills for the same influx

      • So, where does the science go next with this? Would Modern tomography give a better estimate of the size of the chamber(s)? More sensors? Are foreign scientists welcome in Iwo Jima? If this has a potential impact on the US, could/would research come from one of the West Coast Universities? UW, UCLA, CalTech, Stanford, all have $10’s of Billions of endowments. (with lots of Japanese and Chinese students) Hell, maybe even Disney would finance it.

        • Sounds like a job for Kiyoo Mogi!

          And yes, fine grained tomography would go a long way towards understanding this critter. I even think that inSar flights would help quite a bit in understanding the uplift. Ample aircraft are fitted with Sar and inSar in the various military and satellites.

  10. Well! That was quite a read! It is a work of fiction. However the facts and the methods of ascertaining the behaviours of volcanoes are very real. What are computer models? We use them all the time to assess possible scenarios . Models are only as good as the statistics that are fed into them.
    Knowing the backgrounds of all the people involved in this series the facts are well researched and, importantly, understood. These volcanic facts have highlighted the possible disasters that COULD happen.

    A natural disaster such as an eruption or tsunami is only a disaster because life, of any form, is annihilated to such an extent that it impacts and changes a society and natural habits beyond the norm. Natural habitats can recover in time .Unfortunately human societies are often so damaged that the resulting turmoils create yet more disasters of famines, wars and civil unrest when even more lives are put at risk.

    The most important theme running through this series is advanced warning and detailed planning of effective evacuation and other mitigating actions. Prime examples are the present day network of hurricane and tsunami warnings. These warnings have saved thousands of lives already but there are of course no accurate statistics to say just how many.

    Governments of course should not be ostriches. They should lead the way in making provision for the planned safety of the citizens under their care. However each individual can also do their bit no matter where in the world they live. Even if they have no volcanic activity in their locale. How?
    By educating themselves and especially their children. Teach them how to be a helpful , caring and thoughtful member of their society. teach them to understand the need for public safety instructions and to reliably follow them.
    OK ! if you feel like building a Tsunami proof bunker a couple of miles inland and stocking it with several hundred toilet rolls and three years worth of canned hot dogs that’s up to you. The true survivors are those who are thinking enough to pass on their skills and knowledge to others. Those who truly care for each other and next generation and the world we all all share.

    Such a thought provoking series. Many thanks to Henrick, Carl , Albert and Lurking. Hats off to you all.

  11. Hey everybody, we are all “researchers!”

    … where’s my per diem?

    • The reward of research is contributing to invaluable knowledge. As it is invaluable, monetary compensation would be inappropriate. Let’s not mention tenure.

      • I jest. Per diem paperwork is a pain, and there is no funding entity. The last time I was in a per diem situation, I spent most of the evening fighting the cockroaches for the TV remote.

  12. Wow.


    I read the inflation/uplift paragraph maybe twenty times before moving on because the numbers are so. . . incomprehensible? Insane? Beyond belief? If, say, Mt. Hood inflated 25cm in a year–and did it just once–the American media would lose its mind. Miyuki Kaku would die of exhaustion running from one interview to the next.

    Seventeen meters since WWII?

      • Been thinking all day about my uncle, who ran up those beaches and got shot three times between the boat and the trees. My cousins might not even exist if he’d had to run the extra height and distance.

  13. Thank you ALL for your kind comments! I am more than happy that you liked both the series and the final installment.

    As the main author, I suppose it is natural that I now receive most of the plaudits but please! There are a lot of other people who through their contributions have made this series possible and who also deserve our thanks, yours and mine.

    First, of course, comes Carl. Together, we came up with the idea for this series and Carl wrote one of the introductory posts as well as two posts in the main series before other events precluded his further participation.

    Albert’s importance to the series cannot be overstated as when the series faltered, he stepped in and gave me a lot of help and encouragement as well as did a lot of the background research for the latter installments. Not only that, it is almost entirely thanks to his initiative that the series has reached a wider audience. We must also thank Sam Wood, Press Officer University of Manchester, for his kind assistance.

    Then there’s Lughduniense and Hobbes who not only run the FB VC but also keeps this place running, oiling cyber-wheels and de-bugging where necessary, as well as Lurking and Diana who provide much of the social glue that makes this community stick together to thank, especially for their sterling work during the first part of the year. In addition; Sissel, ManoftheMoors and Tyler have lent us their assistance at various points when needed.

    Finally, THANK YOU, dear readers! Without your interest, enthusiasm and support, this series would never have been written, much less contemplated!

    Humbly Yours,


    • As an avid reader of this blog, following along since the first unrest at Bardabunga – witnessing Carl’s almost scary accurate predictions and later the mathematical model predicting the date the eruption would stop (can’t remember the author on that) I can’t help but feel a bit worried..

      Thank you to all involved in this series and keeping the cafe up and running.

      • “can’t remember the author ”

        I believe it was Albert’s regression analysis. He fitted it to a decay curve. I know that I was suitably impressed, and spent the day kicking myself in the arse for not even trying.

  14. Very interesting indeed. I took a boo at one of the cited papers (Nagai et al.) re: If the chamber was destroyed in the Motoyama event, why are all those euhedral phenocrysts in the Suribachi deposits ~1800 years later. The Appendix 1 photomicrographs may illustrate the point better than the figure used in the article. Also from the Motoyama sections it looked like there was a major influx of heat sometime just before the 2700bp event, lots of partially resorbed plagio etc.
    But yeah, that inflation rate is just insane, and the locations of the more recent phreatic events are just spooky.

  15. I wonder how the the countries of China, Japan and the Philippines are going to react when they see or hear about your outcome.Then again what can they do about it ?. Also I am sure we are going to see many webcam hosts promoting the next Krakatoa.
    Great Article, great reading material and from some great people who have devoted their time for others.

  16. Let me give a hearty thanks to Henrik and the crew. Excellent presentation.

    Really like the way that some facts are made more palatable when presented as “fiction”.

    I would also like to extend my thanks to Henrik for service to his country. Seems that fewer and fewer, in my country at least, appreciate those that do the things to keep civil society and freedom thriving.

  17. Hi everyone – sorry I’ve not been here for a while. I’m trying to move sell my house and move and other things got in the way of volcanoes. I’ve just caught up with the last few posts and the splendid story Henrik wrote – what a great way to learn! Thanks for the great series. I guess if Ioto did explode it would bring about a global blanket of dust like Tambora and bring about a few years of weather disruption? It’s nice to be back! 🙂

    • Dunno about “a few years”… The SO2 load will likely turn to sulphate and settle out after about 50 months.

      • Really depends on your perception of time…

        The 50 month figure is how long it take for all of the sulfate to effectively sediment out. At 10 to 15 months it’s down to about half of what the peak was.

        Derived from “Stratospheric Loading of Sulfur from Explosive Volcanic Eruptions” Bluth et al (1997). This plot shows the e-folding times for SO2 to sulfate conversation, and then for sulfate removal from the stratosphere.

        Note: This plot originally appears in my Ruminerian V on the purloined site. If desired, I can bring it over to this one and open it back up for discussion.

        The plot was generated for a one metric tonne SO2 injection so that it could be easily scaled to whatever size SO2 injection you wish to examine.

        • Thanks Lurking! I wasn’t sure how long the effect would last – hence the question mark at the end of my sentence. I’m sure there are computer models that could show how quickly the particles would spread and where – no doubt the northern hemisphere would be worst hit, but the time of year, wind direction etc. makes a difference.

          • In all liklihood, the sulphate screen will be in the Jung layer over the tropics.

            ” alt=”” />

          • At 25degree North, the dust and sulphate would mostly stay in the northern hemisphere. Depending on the size of any eruption, yes, there could be a notable effect on the temperatures lasting 1-2 years, mostly as a colder spring/summer. Not something to be ignored but the world could cope with that. The tsunami risk seems much more immediate and important.

    • Yeah, I’m watching France24 right now. For fear of offending off a lot of people, I’m not making a comment. Charles Martel would be quite appalled. He invented the solution, it’s just a matter of using it.

    • An appaling act, but its just best to just ignore it.

      The more you acknowlege them. The more you play in the hands of IS, but also in the hands of those that will undeniably abuse this attack as an excuse to restrict freedom and spread islamophobia.
      Which judging on the current climate in europe. Are a far bigger problem.

      We are not at war with Islam. But there are those on both sides that have too much to gain by claiming we are.

      • True, but when you are dealing with a simpleton whose mentality is no greater than that of a school-yard bully, they don’t really care if you are harboring hostility towards them or not. The only thing that sort of person understands is brute power.

        “Pax Romana” didn’t come about because they were nice and conciliatory.

        Now… if you want to look at it for what it is, the central plan is to cause internal strife among the population. In that regards, it seems to be working quite well. What should be looked at is any politician who attempts to facilitate this. Who exactly are they looking out for?

        • We are supposed to be an enlightened, scientifically-minded, evidence-based bunch here aren’t we?

          So why did someone post a link to a nasty bit of xenophobic fearmongering that confuses Muslims in general with the radical minority within the faith, one apparently published on a [redacted: name-calling] to judge by the big banner ad at the top promoting a [redacted: name-calling] book from some [redacted: name-calling]?

  18. Hello everyone. I haven’t commented lately but I read those posted by others nearly every day. Great series with a surprising, extremely interesting number one. Congratulations to all who contributed and worked so hard.

  19. Congratulations on finishing this great series. I myself recalled trying to guess the final volcano. Only to raise my hands in dispair complaining that it is probably some obscure volcano in the middle of the ocean everyone forgot about ready to unleash deathly waves. Oh the irony.

    But alas, even if i did post it. Close but no sigare.

  20. Thanks Henrik for a mind-boggling closure of this wonderful series of articles! Iwo Jima never even reached my perception levels until now. I’ll be glued to the seismic news on it, from now on. Thanks to all contributors for a fascinating series! Now that I (with the rest of you) have been promoted by the Mirror, I’ll just take my chair at Manchester University as a volcanic research scientist! (lol). It might pay better than being a librarian. Meanwhile, I await your first full disaster novel, Henrik!

  21. And after all that worrying about tsunamis, the rains from ex-hurricane Kate have just started here. Time to clear out the drains.

    • Beware the monkey grass. (a border foliage for sidewalks and driveways)

      Mine tends to make my driveway into a temporary pond. I’d stock catfish in it, but at 6″ it’s far too shallow and the water drains off in a few hours anyway…

  22. Thanks for a fantastic series of articles! This last piece has for sure been worth waiting for. Amazing work!

    Now for something else. I have a habit of checking the Icelandic earthquake maps a few times every day, but I just realized I almost missed something that might be interesting. A small quake right in the middle of the dead zone! It happened two days ago and only measured M0.5, but considering the location in the dead zone I feel it is still worth mentioning. The depth was 10.8km and it seems to be perfectly lined up with the Laki fissure row.

  23. OT

    Why Self-Driving Cars Must Be Programmed to Kill

    Self-driving cars are already cruising the streets. But before they can become widespread, carmakers must solve an impossible ethical dilemma of algorithmic morality.

    Note: Don’t be too alarmed at an autonomous entity being programed to kill. We have had that as part of out society for years. Anti-ship cruise missiles are exactly that. The more advanced ones simply fly to the target area and look for the best thing to blow up that fits the guidelines programed into it.

    Caveat: 20+ years studying missile systems and engagement scenarios. Not an expert, but I know quite a bit on the subject.

    The spooky part is that with an inbound missile, you know it is coming (if you are doing your job) and can work to keep it from getting you. With a lethal option in a self driving car, you may not get a warning at all. The decision to kill you may only take a couple of milliseconds and you won’t have the ability to fight back.

      • And you hit it square on the head. “HAL” (as presented) was given conflicting priorities. Secrecy and security of the mission was paramount and at the highest priority of his decision tree. Pesky humans just got into the way by potentially waking up from cryosleep and discovering the Monolith developments.

        Something else that Clarke got right – Geostationary satellites.

        “popularised by the science fiction author Arthur C. Clarke in a paper in Wireless World in 1945.”

        July 26, 1963 Syncom 2 was launched on a Delta rocket B booster. A few months later it was used for the world’s first satellite-relayed telephone call.

        BTW, got your Long Johns out?

        “A winter storm warning is in effect for the Olympics and North Cascades through Sunday morning,with 1-2 feet of snow possible by daybreak Sunday.”

        And for those who miss the relevancy of this to Volcanoes… this is in Mt Ranier / Mt Hood territory. With Ranier there is a very real Lahar threat whether there is an eruption or not. As for Mt Hood, it means that the park service is probably gonna have to go risk their lives for the inevitable missing hiker. There isn’t one right now, but it happens quite regularly.

  24. Just a short rumination.
    Now how will the VC Boffins top this series? I wonder? Super volcanoes? That sounds very logical.
    The world is in turmoil ( a little more than usual) this morning and aggression is making rumblings across the world. This is making me very sad and fearful.
    I am more worried about humanity causing “disasters” than Volcanoes.

    However it is a biological fact that when a the number of individuals in a species becomes too great for their habitat to support them, there is a population crash to bring numbers back to a balance. These crashes allow the species survival and the habitat can support the population in full breeding health.

    I would rather be naturally culled as part of a population crash I think I would rather like to spend my last days at least ruminating about the interesting events leading up to a super eruption.This, to me, would be preferable than inhumane attacks from competitive members of other groups of humans. At least following the lead up to a huge eruption would answer many of my questions and I would be prepared then, to meet my maker with a little more understanding of the part of the world’s mechanics that we as a species have not managed to mess up.

    This rumination has been triggered by this post by Wyatt Everhart on the VC Facebook page and I would be interested to watch VC members discuss these findings (even though I probably will not fully understand the physics used in the discussions)

    Off now for coffee #2

    (PS Lurking, I am sorry to raise the Subject of Yellowstone. I assure you my temporary absence from VC was not because I was rebuilding the Anderson Shelter in my back yard. My only prepping activity has been to store enoughbasic food for a fortnight of El Nino weather predicted for this winter by our Met office. This saves me having to hobble about dangerously on Icy footpaths or through deep snow )

    • I’m not sure we can aim to top it, at least not yet!

      I think a return to the smaller, less spectacular posts about specific volcanoes and their quirks… At Least in the short term!

      • Or how about continuing the idea of ‘the 10 most..’
        (‘The 10 least dangerous vulcanoes on earth’ wold definitely break new ground).

        Or we could try to make a sequel, the Vulcan War, with Henrik Skywalker and his father, Carl Vader, their robot Hobs2D2, and a host of supporting characters.

        • keeping on the space theme. maybe something about Planets and their “Volcanoes” ? If they have them If not why not?

          • Oh hell yes!

            The ice volcanoes of Io… the giant olympus mons… The activity still ongoing on Venus?

            What’s not to be

          • Albert I am interested! I need to know to keep up with my Grandson and Step-son’s knowledge!! Grandson is getting a super telescope for Christmas. (Shh! don’t tell him. Santa is using our house as a depositary . He is a little young for this but his Dad will have a wonderful time checking it out and setting it up too!) My step son is really well into Space.

        • Now that is an idea that appeals to me 1:

          “The 10 Least Known Volcanoes on Earth” – What a challenge such a series would pose! To accurately ascertain which ten are the least known and likely to remain so post-publication.

          Now that is an idea that appeals to me 2:

          Although I rather see myself as Imperial Stormtrooper #23 (you know, the one who comes off his bike), I’ll go along with that as long as we hopelessly mix things up by the introduction of characters such as the great wizard Gandalbert the Wise, Dalek Diana, Captain Nick “Bad Form” Wook, Whelpma and her Miracle Dog as well as Lurkian Gray of the League of Gentlemen.

          • I do like the idea with the 10 least known volcanoes on earth! I was totally stoked with the #1 as I never heard of Ioto before. Always happy to learn something new!

            Having said this, a suggestion to tighten the focus: “The 10 least known volcanoes on earth with the potential to go “big” within the next some 100 years” Pretty much the same criteria without the 1 million-death criteria.

            The lesser known Ioto would clearly be a candidate for this – and judging by the enthusiastic feedback after Ioto I’m pretty sure it would be an interesting challenge for both the authors and the reader. Promising candidates for such an series, taken out of the suggestions for #1: Long Valley, Tatun Group, Alban Hills, Atitlan, Amatitlan, Agua or Kuwae.

            Looking forward to all the articles to come! Thank you for the awesome readings so far!

          • I feel that the ‘ten least-known (dangerous) volcanoes on Earth’ might have to include some so little known that they are, in fact, completely UNknown. There are plenty of submarine calderas -and submarine stratocones which could some day ‘go caldera’- in arc regions like the Marianas, or in PNG or Vanautu. Some only recently discovered (Tavui), some perhaps still unsuspected.

            Perhaps St. Andrew Strait might be worth further examination sometime?

          • “Least-known / Dangerous?” I’m showing my USA-centricity, but Dotsero Colorado could massively screw up highway (I-70) and aviation (DEN) commerce.

        • This kinda depends on what counts as a volcano in this context.
          You can write articles about long death volcanos like Devils tower and Zuidwal.
          But also about volcanos which eruptions are so small they can be observed from up close. Resulting in somekind of the Volcanoholic traveling guide.
          You can even have a list of destructive volcanos that are perfectly monitored to applaud that and show the techniques used.

          All three woud make nice series.

          But since we are throwing out ideas. Other fun ideas would be exploring the bad science between movie disasters. Discussions on famous historical eruptions and a series just explaining the science behind volcanos and predictions.
          Its also worth nothing that next year its been 25 years since the Kraffts sadly passed away. Which would be a nice opportunity for a article in their honor.

          Offcource its up to the writers to decide naturally. They did a great job in the past, so i have full faith in the future. Regardless if they use our suggestions or not.

      • Or a debate on why volcanoes on the current Decade program were not on the list? The “omissions” still need to be treated with respect 🙂

        • Valid point! There have been some very good reader-submitted candidates and as we found out, our ten are not the only MDE-capable volcanoes.

    • Yes a human population crash seems to me to be probable and within a time scale that is a tiny fraction of geological hazards that could wipe out comparable numbers. A combination of climate heating, crop failures, starvation, mass migration, pandemic disease…and we have no-one else to blame but ourselves. The anthropocene wont last long.
      Humans may be existing in relict bands by the time Ioto threatens the remnants of humanity.
      No disrespect Henrik, I enjoyed the series of articles.

      (Rescued from the dungeons / Henrik)

      • Peter, how could I possibly object to a belief I subscribe to myself? Because of our biological programming; to always choose the small benefit now in the unshakable belief that the great, later disadvantage associated with it will never materialise, we are doomed. The only two questions remaining are “what will trigger it?” and “when?”.

    • Despite the fact that the term is an artificial construct designed to elicit attention for a media company, it has become a relatively known and understood term. I prefer “Large Caldera event”, but I’m just some bystander watching from the shadows.

  25. Henrik, I wonder at times if it will be a mis-targeted biowarfare agent. With resources running out, any form of warfare will be up for grabs as long as it leaves productive territory usable. That rules out nuclear and perhaps chemical. And explosives wont kill enough fast enough: ‘they’ will fight back. So over to biowarfare. Genomics can reveal racial and maybe tribal differences that might be targeted….subtly. The first – innocent – steps along these lines were taken two decades ago looking for genetic polymorphisms associated with drug resistance or drug intolerance in patients. For warfare an innocuous virus could be engineered to reduce fecundity in a targeted race, the enemy. But the targeting might fail, backfiring onto humans globally. Present day genomics technology has potentially a very dangerous dark side, but in the extremis of over-population who knows what is being done in covert labs, ‘just in case’ ? And those labs may not be ‘ours’. And by comparison with conventional warfare, dirt cheap.
    Yes I’m deeply pessimistic that failure to tackle over-pupulation and cc is going to cost the human race dearly.

    • A similar scenario is used by Humphrey Hawksley in his 2003 novel “The Third World War” (ISBN 0-330-49249-7). Personally, I believe the imminent collapse of our welfare/subsidy societies due to population pressure with not one but several social contracts in place to be a more likely trigger. Civil war, the collapse of civilised society to be followed by what you describe as a result of large segments of the population being excluded from the benefits (such as proper medical care, ample food, western standard of living) because the resources no longer are sufficient to encompass everyone.

      PS. Re “racial and maybe tribal differences that might be targeted” – was not the first – and not so innocent – steps the medical research on twins by Mengele?

      • Not sure of Mengele’s motives. But the possibility of mass migration northwards of diseased and starving hundreds of millions from developing countries might provide a motivation to forestall that event by engineering a population stabilisation or reduction.
        Interesting that the Syrian refugee crisis can be traced back to three years of drought, a million displaced farmers and their uprising against Assad. Maybe its the beginning of ‘the end’, the future in microcosm: the water wars have started.

    • I am a bit more hopeful about our future. Population growth has come down dramatically over the past two decades although there is a lot more to do. We have managed to get passed several crises. The cold war is well known. One lucky escape we had is less well known: the choice of gas for refridgerators was between chlorides and bromides. We chose the former which turned out to be bad for ozone. Bromide would have been much worse for ozone, and by the time we would have been aware of a problem, there would have been real trouble. There are big crises to come. Climate change is going to be a big problem. By the late 2020’s, there will be an energy crisis. Robotification will have a dramatically growing effect on employment. Big companies will be more powerful than governments, and they will need to accept responsibilities they currently deny. (The UK has seen this in the past. Companies that underpay employees find that noone can afford their products .) But I think with effort, all this can be managed.

      For population growth, we need to plan for a peak population around 10-11 billion, with a fair fraction coming from people living longer. For climate change, we should aim to limit the amount while being realistic ( 2 degrees is unavoidable, 3 degrees can still be avoided), while planning for which crops to grow in a warmer, wetter world but with different effects in different parts of the world. We lost almost a decade with the Bush (Jr) administration. Some politicians and companies need to accept that the challenges are real, and some others need to look for pragmatic solutions rather than idealistic ones. We’ll need some luck, but I am optimistic that it can be done.

      • For this we need education and since an educated, knowledgeable and discerning electorate/body of consumers is anathema to politicians and corporate businesses (as proven by the Bush Jr epoch and almost every European goverment), what hope is there? They rarely look any further than the next election or AGM of the (major) shareholders respectively.

        Let me introduce you to my sister in law! Her whole life circles around her need to “keep up with” her group of school-day friends, so appearances are everything. There has to be two cars and two holidays abroad every year. The choice of where to shop is based on the status the vendor provides. Clothes have to brand new and come with a recognised label in order to show that one can afford them. Shoes are thrown away when in need of a polish or a new (half-)sole. She is not an exception, she is the rule and one desired and encouraged as her need to have her ego stoked makes her consume way above true needs – both taxman and businessman agree on the desirability of her lifestyle.

        States are the same. Were the US Government to adjust energy taxation to the levels of European ones, the added tax income on petrol/gasoline alone would result in a balanced budget and the national debt being worked off in a period of time barely exceeding a Presidential term. As a bonus, this would reduce both consumption and emissions. But this would also amount to political suicide, thus it is deferred.

        It can still be done but where is the realisation of the necessity? Where is the will to educate and the courage to implement necessary changes?

        • Publius Quinctilius Varus tried to impose Roman Law and society by force and that didn’t turn out so well for him. Of course, it didn’t turn out so well for Arminius when he tried to consolidate his leadership into a kingship after utterly destroying the Legions lead by Varus.

          Carl’s primary guideline here is to “be nice” So, with that directive, I withhold further comment. However, I do think we need an update to our National Anthem…

      • Slightly OT…..

        I am an eternal optimist. I too think that the human race will survive and likely lose some of the less attractive human traits, such as Stoopidity.

        Nobody has yet realised the population crash has already started. Natural selection in action in this video.
        The more alert, intelligent and less materialistic, who are aware, are more likely to survive than those living in a thoughtless, mass indoctrination technological bubble.
        How many texting individuals have YOU nearly mown down recently?

  26. My brow has been somewhat furrowed during this series. I went back and looked at the Top Ten, then went back and re-read the MDE proposal.

    I even allowed for black swans–‘perfect storms’, and with a couple exceptions I can’t see where the “M’ part of the acronym could come into play. I did consider criminal negligence on the part of the respective civil defence agencies, and that is the most likely cause for the ‘M’ scenario, but still unlikely.

    Of course a ‘100K’ scenario is statistically more likely.

    Kelud: 100K, no problem. I do have an issue with the mention of ‘caldera-forming’ eruptions, to my eyes it seems that you are assuming that the precursors to such an eruption would be the same as that for a 1951-type. I think the precursors would be different.

    Mayon: I see no indications (and I admit that I can’t go out and buy access to the appropriate scientific journals), so I turn to the past–I find no evidence of a previous edifice or sector collapse. I also haven’t seen evidence of an eruption that has affected Legapsi proper. No evidence of magma evolution, either. I’d call Mayon a 10K volcano.

    Taal: More likely, but again the reservation I have is that the precursors to an ignimbrite/caldera eruption don’t seem to be there. I think you’d need a lot more than ten years of seismicity/deformation unrest–look at Rabaul, ten years of inflation and 1994 was just like 1937. There’d have to be a century or so of scientific coverup and/or public apathy for a ‘M” scenario–but i suppose it could happen…

    Cameroon: Similar to Mayon–no evidence of caldera creation, sudden ignimbrite eruttions *from Cameroon* and increased volatile production doesn’t necessarily mean a concomitant change in magma type. I also think a sector/edifice collapse is unlikely–because there isn’t anything in the geologic history of *this* volcano.

    Bali: Actually, i could see political reasons why an eruption from Agung or Batur could surprise a bunch of tourists and cause a lot of deaths. Who wants to have a decade worth of wolf crying? I can’t see ‘M’ worth, but if there was a concerted effort to hide the precursors then 10K could bring down a government.

    Mexico: I’d be worried about sector collapse, but not a ‘M’ worth. I could also see a Masaya-type sulphur degasing event rendering Mexico DF uninhabitable. Which could also bring down a government.

    Aso. (Great background and insights, by the way). I can’t see an ‘M’, but with disease and riots I could easily see ‘100K’ A VEI-6 could also destroy several nations’ economies. The scenario outlined with Ioto–what should/can the JMA do?–is more problematic here. Instead of 1000KM out to sea, Aso is *there*, plain to see and harder to hide.

    Campi Flegrei: Italian civil authorities are screwed here. I mentioned the combination of massive governmental negligence/dithering and an apathetic populace could cause an ‘M’. I also touched on decades of seismicity/tumescence–guess what, here it is! The best thing to hope for is that homo sapiens has killed itself off before the Bay of Naples unzips.

    Apoyeque: Interesting choice. I think that 500K could die without an eruption–lake methane, landslide, a small eruption cutting an escape route then causing panic/riots–but this also brings up a point–where does riot, revolution, economic upheaval fall in the proximate/secondary/tertiary cause flowchart? Hard to blame a volcano for the follies of man. 🙂

    Ioto: Perfect. Agree 95% and that’s good enough 🙂 (I also need to get of my butt and start writing again, lol.) I agree, between the eruption and tsunami this could be a ‘1+M” and when you add societal disruption and disease… Another thought: I’d like to see China’s increasing economic heft result in an increase in their scientific curiosity. This scenario begs for more research, and the more brains involved, the better!

    Perfect example of the dillema ‘when do we let the public know?’

    I’d also like to add Rainier. She could kill ‘100+K’ in thirty minutes with no warning–and no eruption. This time politics and apathy wouldn’t be a factor, because that ship has already sailed!

    Great list. Thanks again!

    • Science is all about questioning, going over the available evidence, searching for new facts, testing of hypothesis in order to arrive at a new and better understanding. Our series never made the claim that it was “definitive” and we have tried to “make the case for” and explain why in each of the articles. Were I to bring this up again in response, I would only be repeating information already published in each of these articles. I’ll just illustrate this by raising a few points in relation to Mayon:

      Before 1980, Mt St Helens was sometimes referred to as “The Fuji of the West”, so perfect was its edifice perceived to be, and no-one envisaged its dramatic 1980 collapse. Mayon (as explained in the article) sits on two major tectonic fault lines and recent research has shown that there are already faults/cracks in several places that could indicate incipient collapse of the edifice. Also (as explained in the article), there is evidence of many flank eruptions in what is now the middle of urbanised areas. Even the PHIVOLCS Mayon observatory is built upon such a monogenetic cone. In addition, Carl said that there was evidence of ring fractures around Mayon, but as I could not verify this information from the scientific papers at my disposal, I chose not to include this in the article.

      • Thanks, Henrik!

        Ah, St. Helens. Before CNN, before Internet. Before college, too–so I had to wait months for scientific journals to make their way to my high school!

        I’d love to read some more hardcore science about Mayon–come on, lottery–I can’t see a sector collapse because there’s no overhang, and no caldera/edifice collapse because as far as I can tell, there’s no shallow magma chamber.

      • Damon, good analysis, but I think your assumption that large-scale volcanic eruptions will show long-term pre-eruptive behavior indicative of an upcoming large eruption is not all that true.

        Given, in historic times, we don’t have any VEI-7 eruptions where we’ve tracked the pre-eruptive sequence, but a lot of geological evidence shows that many rhyolitic eruptions can go from a low background level to a full-scale eruption in an extremely quick fashion.

        Here are my general thoughts –

        Kelud: 1m very unlikely, at least in the geologically near future. Kelud seems too steady with VEI-4-5 eruptions, and would likely need a VEI-6 or higher to break into a 100k scenario. If there wasn’t as much active mitigation here, it would be a different scenario, but Kelud is very well monitored as we saw during the recent eruption which claimed basically no lives.

        Mayon: It hasn’t historically had any truly enormous eruptions or flank collapses, but in some ways, this is a signal that it may be primed to topple. Volcanoes are generally cyclical assuming a constant rate of magmatic input. They will only grow so tall before they become structurally unsound regardless of an overhang or not. The higher and more prominent the edifice grows, the higher the likelihood that you’ll see a caldera-forming eruption or flank collapse. Given Mayon’s activity and other signs, it is a very “ripe” volcano for doing something much bigger than it has historically done. Also, just look around at all the neighboring volcanoes if you think it doesn’t have the potential to do this. All the surrounding volcanoes near Mayon have either had a caldera formation, or a flank collapse, many of which were smaller than Mayon was in the first place. I would personally place Mayon higher on the list to be honest.

        Taal: Taal is a pretty easy selection. Long history of large ignimbrite eruptions, very close to an extremely dense population center. Even if there aren’t current signs of one of these large eruptions, this could easily be a MDE volcano. Also, Rabaul is a sample size of 1. Pinatubo only had a few months of lead-up time prior to its eruption, which was significantly larger than Rabaul’s, and there was very little inflation prior to the eruption as well. Part of the issue is that a lot of the lead-up to a large eruption may not manifest itself on the surface, so we may not know if a volcano is prepping for a major eruption or not, even if it has been prepping for 10+ years. Tarawera in New Zealand unzipped in the matter of days to form a VEI-5, and recent chilean eruptions have gone from quiescence to full eruptions extremely quick.

        Cameroon: I tend to agree with you here. Yes, a large flank collapse would be an issue, but it doesn’t seem to be one of the most likely candidates since it has a much broader base. Also, you could list quite a few other volcanoes here near highly populated areas which would also have equivalent disasters if they simply suffered a major flank collapse. Merapi for example would seem to me to be a more likely candidate to suffer a flank collapse in the geologically near future, and the consequences would be just as, or even more dire.

        Bali: I like this selection, even if its not selecting a single volcano. Would it end up as a MDE event? Who knows, but the VEI-7 eruptions in Indonesia have tended to blanket the entire island where the volcano is a part of. I think we would need a VEI-7 to get close to a MDE event here, but we know these volcanoes are definitely capable of that. Part of proper mitigation is in the capability to evacuate an area, and when a large population center is located on an island with no bridge away, it makes escaping the island an extremely tough proposition.

        Mexico: Popocatepetl’s biggest risk is a large sector collapse, which would be HUGE if it came from such a tall volcano. A true black swan event would be a sector collapse directed to the northwest, which would send a directional blast and debris avalanche right into the heart of Mexico city. This is a very unlikely event, but would be beyond just a MDE if it were to happen.

        Aso: We would need a VEI-7 to see significant life-loss from Aso. The caldera which Aso sits inside is populated, but not heavily populated. With that said, a VEI-7 here would be a big big big problem not just for Japan, but likely for the world economy as well. The only caveat here is that you could say this for any of the volcanoes in Kyushu, all which seem just as likely to go big as Aso.

        Apoyeque: This is a pretty cleary large explosive volcano next to a high population center. Similar to Taal, except even closer to the city, this is a disaster waiting to happen.

        Ioto: Agreed on this one, pretty clear risk.

    • Quite a valid rebuttal, but the idea is that the M criteria results if things go bad in the worst way. Liklihood? Very remote, but as you noted, that is the realm of the swans. The way you defend against swans, is to learn everything you can about the threat, then keep watching and learning. If you are lucky, you can see it comming.

    • This is an excellent set of comments. In some cases you are probably right that the 1M potential may not be there, although the risks there are are sufficient to warrant enhanced monitoring. Mount Cameroon is a good example: the volcano is huge and very poorly known. It has been mainly ‘friendly active’ since records began. The main population centres are some distance away. I see its inclusion as a call to study this volcano, and find out what it can do. It would be a bit dangerous to assume the past few hundred years are _all_ it can do. Other volcanoes have been mentioned. Guatemala city was discussed by a number of people: it was felt that the risks were a little lower than for Managua, based on published work, but this is not definitive. Mount Rainier is a real threat but already well studied. I think little would have been gained by including it, in terms of encouraging new studies. It probably would have made more news in the US but that wasn’t the objective. Population densities outside of the western world are much higher than many are used to: eruption hazards can be correspondingly higher. One thing I read is that volcanoes with recent eruptions have lower population densities in their environment. But after 100 year of quiescence, that effect goes away and people move in. And risks increase.

      To my mind, the series aimed at making people think beyond the box of ‘safe expectation’. The question often is not what it will do (‘more of the same’) but what it can do. Apoyeque is one that based on the immediate past, will do nothing. Looking back a bit further into the past gives a much more frightening scenario.

    • There’s a joker in the pack in some volcano-tectonic scenarios, and he stuck his nose out in NZ a bit over hundred years ago: Tarawera.

      I’ve said it before, I’ll say it again: That was a bloody great basaltic dyke shot up from a deep source with truly astonishing speed and violence. It went from nothing, to strong seismicity, to full eruption, to a VEI 5 over and done with, ALL in *six hours flat*. I question exactly how much premonitory activity we would pick up even with modern monitoring technology; it was that big, that violent, and that fast.

      Now, what would happen if such a dyke, instead of simply breaking surface and erupting, intersected a large body of near-eruptible rhyolite? I personally believe some NZ systems – and, by extension, comparable systems elsewhere – could be capable of going from a ‘standing start’ to a high – as in maybe 7 or 8 – VEI eruption far, far faster than our worst fears. I know such a mechanism has been suggested for at least some of the large and very violent Taupo eruptions.

      Definitely one to think about.

      • I absolutely and completely agree with you Mike. Tarawera is one h*** of a scary event and as you say, what would happen if 5 km^3 of juvenile, 1300 degrees Centigrade hot basalt shot into a major magma chamber? It is definitely an event that makes Lurking’s Black Swans no mere theoretical oddity.

        • Hey, they aren’t “my” black swans, I’m just a fan of the idea. Taleb is the one who wrote the book on the idea.

      • I’ve commented on this before on here, but I personally believe Tarawera to be a failed supereruption. Well, maybe that’s a bit misleading. My personal thought is that the basaltic dike that shot up from depth probably did pass through a lot of rhyolite, but didn’t heat it enough to make it all eruptible. If the dike stalled and didn’t make it to the surface however, I think it would have been almost a completely different scenario.

        Personally, I tend to think the entire region beneath the Taupo Volcanic Zone is a rhyolitic crystal mush. The only thing that determines the size and location of an eruption is where a basaltic injection occurs, and how much rhyolite it heats to an eruptible state.

        • There’s also the possibility the the Tarawera rhyolite was notably depleted in volatiles – remember, the basalt propagated upwards through the feeder dyke for Okataina’s previous eruption, a series of domes extruded in, I think, the 14th Century, when it would have been pretty well de-gassed, at least in that part of the system

        • From what I can remember from reading papers on Taupo, (various), is that when it went caldera, the collapse was in a series of trap-door collapses of the roof, sort of like tiles falling out of the ceiling in succession, and that chemical analysis of the various stages of the ejecta showed “almost no zonation” from start to finish. Meaning that the entire mass went up quickly and/or that it was well mixed. Given that the floor collapse was a sequential event, I’m leaning towards the “well mixed” belief. It also seems that Taupo was just the latest stage of a previous large caldera event (Whakamaru caldera?) and may have had a magma chamber that was built from the previous one, or was closely related to it. That system did show zonation if I remember correctly. If I can locate the reference, I’ll tag it here.

          Image from via Google image search. Probably pay-walled. If anyone looks into it, you will find that the North Island is quite littered with ancient Calderas. Some overlapping, others not. About 240,000 years ago, Rotorua, Ohakuri, and Reporoa were all in some sort of eruptive state since tephra from each site has been collected and dated to that period of time.

      • Michael, thanks for bringing up Tarawera. Getting away from the societal and back into the chemical…

        Are there any other instances where a basaltic batch has made it to the surface, and *not* melted slushy/mushy acidic magma to the point of eruption? Augustine was the first time I’d read of magma mixing and basalt reactivation of dacitic slush in so many words. However, no basaltic eruption. Hudson and Fimmvörðuháls/Eyjafjallajökull, initial lightly evolved basalt followed by andesite.

        There was the Ape Cave eruption of St. Helens, but maybe that was an eccentric eruption that never interacted with the MSH plumbing.

  27. Oh and thank you to all of the hard workers, fantastic reading, completely hooked.

    • I don’t think so, that will just make the leading edge break early. The old notation of it being a “tidal” wave, though incorrect, was accurate in that the thing is essentially a rise in the sea surface level. Think of it as a large dome of elevated water.

      • My wondering comes from the lack of tsunami reports from the US East Coast ports during the 1755 Lisbon quake. The tsunami would have arrived in Boston and New York and Charleston and Savannah during daylight hours yet, it didn’t (if it did, no one reported it or no one’s found those records). Modeling suggests the wavefronts “broke” on the edge of the continental shelf and the tsunami’s energy dissipated which is why I wonder if the same would happen here.

        I would like to see some modeling. If I were a grad student I’d make this volcano’s hazards my thesis priority, that’s for sure!

        • Rummage around with the Pappus Centroid theory and the volume under a sine wave. It will give you a dissipation curve for the wavefront vs range traveled. Its valid for a point source style of energy release. The Sumatra and Japanese tsunamis formed over a large area and traveled as a focused planar wave.

          • Heres a good place to start.


            If you take a look at the solution for the torus, you can determine what the individual terms are after you locate the formula for the area of a circle and replace it with your area under a sine curve formula. When I did it, I threw away the negative half the curve and only used the upper half. Using the negative half would point you towards the amount of draw-down that the tsunami would possibly have as it is arriving.

            The important thing to remember is that this represents a point source radiator. Say, a very localized sea-floor uplift or half of an island suddenly falling into the water.

    • I wouldn’t know, but I know of a specific exception to that, which would be the area around Hangzhou. Despite only having a fairly middling tidal range, it is home to the largest tidal bore in the world. This is down to the bathymetry. It’s just about a perfect amplifier of wave height, and so turns a tide of (if memory serves) around 6-8 metres into a 9 metre tidal bore at its biggest.

      I have often wondered if the “Great Flood” of 1606 (or 1607, as the calendars were in the process of changing from Julian to Gregorian ) that affected South West Britain was an extreme storm surge amplified by the bathymetry of the Severn Estuary…the site of Europe’s largest tidal bore.

      Some say the event was a tsunami caused by slippage at fault some way South of Ireland. Storm surges tend to peak with the high tide, and according to one reading of the date, a large tide was due that morning…which was so stormy it forced the pilgrim fathers to take shelter in Plymouth en route to the American continent.

      • Odd… I always thought the Pilgrims landed at Plymouth because they ran out of beer. (beer was the common method of keeping water drinkable on long voyages at the time)

        • That would be some massive indictment of their quartermaster, if they ran out of beer so early in the voyage.
          No, the records of the storm itself are fairly clear by the standards of their day.
          Bringing it back to tsunami effects on the Chinese coast, the normal tidal bore is already a pretty fearsome beastie, even for spectators (who seem to be frequently caught out by the unpredictable nature of the wave).
          It was a friend of mine, Stuart Matthews who first surfed this wave back in (I think) 86. He tells me that when he did so, even as an international level competitive surfer and a veteran of tidal bore surfing, it was all he could do to get to his feet for 11 seconds riding a 10 foot foamball, followed by a 30 foot swell. Then his board’s fin caught a mudbank, as did the support vessel’s screw, and both were wiped out. He ended up having to save the lives of his support crew as they were washed a couple of miles upriver.
          Hangzhou is a major city as The Quiantang river is lined with understandably formidable flood defences, which even so are frequently breached by the wave. The bathymetry is good enough that the wave comes upriver with every tide, not just the springs (as is normally the case).
          The thought of a tsunami running into that bay doesn’t bear thinking about.
          Plenty of videos on youtube showing people being swept in.. search for Quintang Dragon tidal bore.

        • It still is, so far as I am concerned, GL. It’s about the only thing keeping the British traveller sane whilst voyaging across any small corner of the UK against a tidal wave of petty bureaucracy, insane ticket schemes and broken rolling stock.

          Sorry. I ought to go to bed.

          • Sleep is always good. Provided you have control over it. I did a 36 hour stint awake again, mainly because I flop around until the alarm clock goes off. So, I was quite tired last night. Dozed right off, sprang awake at 2:36 am. Knew that wasn’t enough and went back to sleep only to wake to the dog checking to see if I was edible yet. Tonight, I fully expect to flop around again. The only saving grace is that there is a pretty hefty thunderstorm system rolling though soon. I can sleep like a baby if it’s storming heavily. My wife can’t. Storms driver her nuts. They have ever since a tornado took off a roof up in Mississippi. (yeah, I’ve been through tornadoes as well as hurricanes. I guess I’m blessed.)

  28. Just throwing out an idea here. If we consider the sites of the recent phreatic explosions as defining a line of weakness where infiltration can occur. Then we get a roughly ring shaped structure with Motoyama at the centre. This would partially explain the difference in inflation rate at Suribachi, which lies outside of the weakened area, but still above the chamber. Its very interesting that *both sides* of the ring have eruptions at the same time.

  29. Once again a green star at IMO’s Vatnajökull map; Bardarbunga.

    Monday16.11.2015 12:39:48 64.621 -17.401 0.5 km 3.2 99.0 6.4 km ESE of Bárðarbunga

    There was also some deep activity yesterday morning, most of it under the Trölladygnja/Kistufell area

    Sunday15.11.2015 06:27:05 64.601 -17.446 15.0 km 0.5 99.0 5.8 km SE of Bárðarbunga
    Sunday15.11.2015 06:27:04 64.722 -17.645 26.3 km 0.7 99.0 10.7 km NNW of Bárðarbunga
    Sunday15.11.2015 04:05:09 64.850 -17.274 15.7 km 0.6 99.0 5.3 km SSW of Trölladyngja
    Sunday15.11.2015 04:04:17 64.827 -17.278 17.6 km 0.6 99.0 6.1 km NNW of Kistufell
    Sunday15.11.2015 04:03:36 64.833 -17.259 16.5 km 1.1 99.0 6.3 km NNW of Kistufell
    Sunday15.11.2015 04:03:30 64.842 -17.270 15.8 km 0.9 99.0 6.2 km S of Trölladyngja
    Sunday15.11.2015 04:03:14 64.855 -17.291 17.6 km 0.4 99.0 5.1 km SSW of Trölladyngja
    Sunday15.11.2015 04:03:08 64.836 -17.275 18.6 km 0.5 99.0 6.8 km NNW of Kistufell
    Sunday15.11.2015 03:51:18 65.208 -16.359 12.2 km 0.7 99.0 3.8 km N of Herðubreið

    Source IMO

  30. I am looking for a book on Volcanism, the basic stuff, as I know not that much about the subject.
    I saw ‘Hans-Ulrich Schmincke. Volcanism’. Is that a profound work? Or perhaps could someone recommend some other title? 🙂
    Thanks in advance!

      • Thank you Henrik,
        Well, no, I guess the title is scaring me off a bit… to popular maybe? 🙂 I think I am looking for kind of handbook where questions are answerred, like, what does a shield volcano make a shield volcano, how does decompressing melt work, what was theolitic basalt again and some other questions 😀 …
        I read so many interesting things here, but have the urge to read things back before the info nestles in my brain. A blog like this is supercool but awfull trying to find info back in. :/
        A book with the basics would help very much.

        • A few choices to start with might include ‘Volcanoes’ by the late Peter Francis, ‘Volcanoes’ (same title, different book) by Robert & Barbara Decker, and of course the creme de la creme of volcano books, ‘Encyclopedia of Volcanoes’ by Haraldur Sigurdsson & Bruce Houghton

          I’ll have a look on my bookshelf to see if any others might be relevant

    • Not strictly a volcanism book, but “Global Tectonics 3rd ed” is a really nice work that puts much of the driving action into perspective.

  31. Nice 2 C VC is back 🙂

    WOW! Loto – sounds like a cute little, fluffy puppy name – is really a sleeping, terrifying dragon.
    What a pulzsating article. Thank You 🙂
    I dont know, what the next series could be, but i would really like to read something about global Warming effects having on the earths volcanic systems. Are there any thoughts? ☺️

    • Volcanoes underneath big glaciers may see a reduction in pressure as the ice melts, and that in principle could trigger eruptions. Mainly Iceland and Antarctic islands, I would guess, and not for another century (or two). Something similar may have have happened after the ice age. Other than that, volcanoes don’t care too much about the local temperatures

      • I’ve thought for some time that the end of the Ice Age. with removal of a heavy ice covering, might have been a contributing factor for the wave of caldera spasms in Alaska during the late Pleistocene/early Holocene

        • There is pretty well-documented research and evidence of a big basaltic volcanic flareup in Iceland after glacial rebound.

          In Kamchatka, I read some research that interglacial periods resulted in a higher frequency of eruptions, but decreased volume of large eruptions. Increased glaciation seems to bottle up volcanoes, allowing them to build more pressure before it gets released. Of course, when you remove said pressure in a very quick manner, who knows.

    • Thank you for that Lurking. Absolutely fascinating. I would have to read up more to be clear but endophytes could be a safer and ecologically more acceptable way of protecting crops rather than using more questionable insecticides. I do know that certain grasses produce toxins that kill competitive plants maybe with more research this may be a safer way of weed control.
      Obviously humans have always been ingesting these fungi as part of the daily diet . It would be interesting to find out just how important they are to human health also.

      • That is interesting. What are the stations to the south and east doing? is this re-inflation of good old Barda?

        • According to this article it is re-inflation (you will have to use translate to read it )

          “Apparent expansion is the caldera region and change the seismic activity, which indicates that the magma Collection has started the carton. Kristin Jonsdottir geophysicist says this is not abnormal. Bárðarbunga is, however, little known to the volcano and will continue to be monitored.”

          I could not find any up to date data on the other stations to see what they are doing, had to dig deep to find what I did

          • There’s now a summary in English on the RUV page. Nice, thoughtful Icelanders.

            “The monitoring group at the Icelandic Meteorologica Office (IMO) met this morning to discuss recent measurements around Bárðarbunga volcano. GPS data show signs of inflation in the area around Bárðarbunga which suggest magma recharging beneath the caldera. These signals have become clearer in the recent months. It is not uncommon that such inflation signals are measured after volcanic eruptions. For example the volcanoes Eyjafjallajökull, Grímsvötn and Hekla have all shown such behaviour. At a similar time the number of earthquakes with magnitudes between 2.5-3.8 has increased but otherwise the seismicity has not changed significantly.

            Bárðarbunga volcano is being monitored 24 hours at IMO and there are currently no signs of an impending eruption. The Civil Protection Science Board has planned a meeting to discuss Bárðarbunga.”

          • There is a suggestion that the intrusion causing this displacement is shallow (1-3 km), not from the deep source that created the pattern seen last year.

            My source is a paper published a couple of weeks ago and is posted on the IMO site.

            It says ” possibility of a shallow intrusion (expanding horizontally) or shallow gas accumulation from a degassing magma body at depth”

            There are papers out there that suggest that the pattern of displacement last year was widespread therefore a deep source (11.5 km deep) based on the ratio of horizontal vs vertical displacement.

          • That’s interesting. Thanks for posting. I’ve had a dig around on both the English and Icelandic IMO pages for the article you mentioned but don’t seem to be able to track it down. (There is an illuminating one about sewerage in Reykjavik, though.) Any clue on title or author, please?

          • Thanks. I should have dug deeper! Very interesting. I didn’t understand the second presentation but the conclusions are clear enough.

            It’s amazing how fluent other nations are in English, but the ambiguity in this sentence made me smile: “Installation of additional GPS sites closer to the glacier will help *constrain* the source of the deformation.” Would that it were so easy!

  32. There is a new tremorish signal appearing at Bardarbunga or Tungnafellsjokull for a while now, and is a bit localised. Given the frequency range of mid to high, it could be hydrothermal activity. The signal is very similary localised, as was the harmonic tremor pulse that appeared also on mainly VON station a few weeks back. This current signal tho has some affect on the DYN station asweel, but not much.

    Data by IMO.

    • Forgot to add DYN station for comparison.
      And no. Its definetly nor wind noise or human activity. 😀

      • Noticed that too Down Under. Could the source of it be more to the south? Grimsfjall shows it clearly too. And SIL jok, hae, vot, iey more weak…

  33. As a small adendum to anybody who wants to do more of their own searching into possible MDE volcanoes – here is an interesting little list I compiled. These are the volcanoes of the world that have over 1 million people living within 30 kilometers of the volcano. I use 30 kilometers as the base because the GVP allows me to sort through their database at a 30 km interval, and also because 30 kilometers is a distance that you would expect to see a pyroclastic flow travel in the event of a VEI-7 eruption, or a large VEI-6 eruption.

    One note on these is that many of these volcanoes may not be capable of eruptions this size, and many are understudied. It’s a good list to look out for in terms of potential black swans.

    Laguna Caldera – Luzon 7,073,814
    Tatun Group – Taiwan 6,735,396
    Tangkubanparahu – Java 5,729,309
    Malabar – Java 5,685,941
    Penanggungan – Java 4,605,710
    Ungaran – Java 4,595,534
    Merapi – Java 4,348,473
    Arjuno-Welirang – Java 4,143,137
    Vesuvius – Italy 3,907,941
    Guntur – Java 3,412,038
    Cereme – Java 3,058,015
    Merbabu – Java 3,019,783
    Campi Flegrei – Italy 3,006,865
    Alban Hills – Italy 2,962,194
    Ilopango – El Salvador and Honduras 2,948,989
    Kawi-Butak – Java 2,927,446
    Slamet – Java 2,904,026
    San Salvador – El Salvador and Honduras 2,857,563
    Arayat – Luzon 2,805,269
    Telomoyo – Java 2,794,587
    Salak – Java 2,675,904
    Kendang – Java 2,601,697
    Agua – Guatemala 2,530,449
    Guazapa – El Salvador and Honduras 2,488,228
    Pacaya – Guatemala 2,454,482
    Sumbing – Java 2,425,607
    Talagabodas – Java 2,388,005
    Galunggung – Java 2,382,939
    Taal – Luzon 2,380,326
    Lawu – Java 2,344,575
    Perbakti-Gagak – Java 2,333,456
    Malinche, La – Mexico 2,324,232
    Gede-Pangrango – Java 2,315,469
    Tampomas – Java 2,301,649
    Papayo – Mexico 2,207,308
    Lamongan – Java 2,193,829
    Wilis – Java 2,150,615
    Kelut – Java 2,087,876
    Sundoro – Java 2,086,299
    Guagua Pichincha – Ecuador 2,064,475
    Barva – Costa Rica 2,004,665
    Masaya – Nicaragua 1,914,707
    Dieng Volcanic Complex – Java 1,886,942
    Atacazo – Ecuador 1,837,303
    Karang – Java 1,753,655
    Hainan Dao – Southeast Asia 1,731,229
    Banahaw – Luzon 1,698,285
    Irazu – Costa Rica 1,667,528
    Papandayan – Java 1,637,971
    Toluca, Nevado de – Mexico 1,626,432
    Iyang-Argapura – Java 1,601,344
    Muria – Java 1,587,867
    Hakoneyama – Honshu 1,543,563
    Patuha – Java 1,516,827
    Tengger Caldera – Java 1,420,878
    Masaraga – Luzon 1,390,760
    Rinjani – Lesser Sunda Islands 1,374,441
    Apoyeque – Nicaragua 1,342,581
    Izalco – El Salvador and Honduras 1,272,308
    Santa Maria – Guatemala 1,259,600
    Santa Ana – El Salvador and Honduras 1,240,131
    Coatepeque Caldera – El Salvador and Honduras 1,210,307
    Isarog – Luzon 1,208,269
    Karisimbi – Africa (central) 1,198,124
    Pululagua – Ecuador 1,192,411
    Muhavura – Africa (central) 1,189,226
    Harunasan – Honshu 1,185,012
    Corbetti Caldera – Africa (northeastern) and Red Sea 1,171,948
    Silay – Central Philippines 1,167,963
    Mayon – Luzon 1,166,441
    Visoke – Africa (central) 1,162,209
    Iriga – Luzon 1,159,509
    Pinatubo – Luzon 1,148,684
    Almolonga – Guatemala 1,126,942
    Santo Tomas – Luzon 1,122,253
    Akagisan – Honshu 1,116,366
    Apaneca Range – El Salvador and Honduras 1,113,282
    Natib – Luzon 1,050,509
    Acatenango – Guatemala 1,042,836
    Iztaccihuatl – Mexico 1,036,172
    Semeru – Java 1,022,197
    Etna – Italy 1,016,540
    Fuego – Guatemala 1,016,339
    Nyiragongo – Africa (central) 1,006,436

    • Note that most volcanoes from the MDE program ARE on this list with a few exceptions (obviously Ioto being one of them).

      Looking through the list, Agua volcano in Guatemala always strikes me as a volcano on here I simply never want to hear about waking up. It checks off way too many high risk marks for me to be comfortable with.

    • … and for anyone unfamiliar with the idea of a “Black Swan”, Talebs definition is pretty much like this.

      1. The event must be so statistically unlikely that it is effectively assumed to be zero.
      2. I must be catastrophically profound in it’s occurance or effects.
      3. It will be logically argued away (or explained) after the fact. (such as, If only we had known about “so and so” )

      FYI, the likelihood of occurrence is usually at about the same (or less) probability of standard deviation levels in a normal distribution at or beyond 3 sigma.

      This is not the stated requirements made by Taleb, just what I can remember of them. Non catastrophic psuedo black swans appear all over the place and are much more common than one would assume. For example, The average female bust is 34.80393 inches with a one SD value of 2.735157568 inches. With a sample population of 255, the 99.9% confidence interval is 34.2 to 35.4 inches. That means that from a random sample, 99.9% of the time, a purely random sample will be within that range. Yet you see examples of women outside that range all of the time, such as Kate Upton or Colleen Camp (Yvette from the movie Clue), Raquel Welch, and Julie Newmar. Examples from the other side of the curve are Agnetha Fältskog and Dita Von Teese. (both falling into the “eye candy” category in their own right. And proving that bust size isn’t everything… though a recent Mythbusters episode found that a sizable chest could garner a 30% increase in tips from male customers… and a 40% increase from female customers.) {Okay ladies, what’s that all about? The increase from male tippers I can see, but I would have figured that female customers would have had the reverse phenomena from a competition point of view. What gives?}

      Caveat: This data set specifically looks at what body form is selected for movies and TV. In other words, what is idealized, packaged, and fed to the general public. That means that it probably had a huge selection bias and is likely not suitable for judging everyday average people. The same could be said of the volcanoes that we study and research. We are biased to look at the ones that are well known… the ones that have done something to get our attention.

      Taleb’s principle argument (In “The Black Swan“) is that the Gaussian distribution does not properly account for the more rare events and due to that, people overly assume that the likelihood of rare events is easily dismissed with little to no consequence.

      My take on it, is that the distribution is just fine, as long as you remember that rare does not mean impossible. There’s always that infinite probability idea. (See Rumarian X)

      And a profound thanks to William Sealy Gosset(aka “Student”), who pioneered the field of statistical analysis of a small sample group to determine the characteristics of a larger population. His work gave us a better and more consistent beer.

      • An alternate idea with regards to the tipping ratios. Is is possible that women see it as more of a curse and in sympathy for the burdened woman, tip more?

        And another possibility… an enlarged bust could send a subliminal message of being with or recently having a child. In this case, it would be a matter of supporting a recent or soon to be mother. I actually like that scenario since it actually makes sense on a species/tribe survival level. Who better to know what a pain in the arse it is to raise a kid than another woman?

    • I can’t get gvp to do that search for me – so which ones have 1 million within 5km (and so are vulnerable to tiny eruptions??)

      • That is hopefully very rare as you are asking effectively for a major city build inside a caldera ( significant volcanoes will extend for more than 5km from the centre). Naples is probably the only one? Perhaps some places in Mexico, as often eruptions there occur at a new location rather than an existing outlet. But those future sites won’t be listed in the GVP yet.

    • Popocatepetl?? Mexico City has 21 million and on the other side Puebla with 2.5 million. When a city is greater than 60 km in diameter it would be impossible to make the list unless the volcano were inside the city.

  34. Thanks Henrik and all others that gave us the information on the 10 MDE volcanoes. I’ve really enjoyed the series. Now, what is our next adventure in all things volcanic? 🙂

    • What I’d like to see?

      World’s smallest magmatic eruptions.

      Volcanoes with no geological explanation (so far) for their existence.

      Volcanic systems with the longest repose time per the geologic record, (not societal, Lamington and Bezymianny for examples)

      • A couple of offers for the smallest magmatic:
        (1) Marion Island 2004:From GVP:

        “A small volcanic eruption was observed on 24 June 2004 by a member of the South African National Antarctic Programme’s (SANAP) over-wintering team on Marion Island (figure 1). While conducting fieldwork in a mountainous area on the S part of the island, David Heddings was able to video an eruption that comprised gas and small pieces of scoria (a few centimeters in diameter).”

        (2) Haven’t got a reference for this one: On Kilauea some years back. A dark and wet night, HVO seismometers recorded a shallow quake swarm on the rift zone…but nothing was seen, and they weren’t going to venture out to look. Next morning a survey trip found about 3 cubic metres of fresh basaltic scoria round a steaming fissure

        (3) An accidental eruption (Krafla 1977), as described here by the HVO

        • Three cubic meters…that’s what, about a VEI minus two and a half? 🙂

          For longest repose time, I would assume that that has to have been followed by an eruption, or else it devolves into a contest of “name the oldest extinct volcanic system you can think of”, someone names sagduction greenstone belts from the early Archaean c. 4BYA, and it’s game over.

          Even then, repose time is a tricky thing to define. Must there have been *no* magmatic activity expressed on the surface, or are long gaps between successive *large* eruptions also counted, even if peppered with small ones? So, do the half-million-year-plus gaps between successive caldera-forming events at the Yellowstone hotspot qualify? If on the other hand there must have been *no* surface magmatism, how sure can you be that you haven’t overlooked one of those VEI minus two and a half events? Volcanologists could have missed one of those by not looking under some single, specific random rock on a mountainside somewhere.

          • I could have phrased that better–“Volcanic systems with the longest repose time per the geologic record–and then erupted.”

            I can think of one definite and one probable eruption far along the Hawai’ian Chain in 1955-1956–millions of years after the hot spot had passed by. (And this brings up a semantic question as to whether this was a rejuvenation or a new magmatic system…)

  35. Guys, just out of curiosity, i want to pose a question.
    (and please excuse my ignorance in that matter – i am just a newbie here)

    Why is not possible to “relief” a volcano by piercing through its top and opening a gap, which would allow the pressured magma underneath to surface without a real eruption?

    This piercing could happen with some remote tools which could blast a tunnel in order to free some space and lower the pressure.

    Btw this could be similar to the way people have relieved “swelling eye” in the past or in boxing matches – by introducing a tiny cut on the skin, so that the pressured blood can go out and relief the swelling spot.

    Please let me know your thoughts on this and again .. excuses if this is a very naive oversimplification of the problem 🙂

    • The reason is the same why piercing a hole in a shaken bottle of pepsi, or for that matter a Yellowstone geyser, is risky. The hole reduces the pressure. But at lower pressure, more of the volatiles (CO2 in the case of pepsi) become gas: they expand by a factor of 1000, and suddenly you find that instead of decreasing the pressure, you have greatly increased it. This leads to explosions. Volcanoes and pepsi are funny that way.

      So a better way to prevent eruptions is to increase the pressure. Pile a thick glacier on top of the mountain, or a deep ocean!

Comments are closed.