Guest post by Tallis
My father and I disagree on a lot of things from religion, politics, career, and more; One of the things we disagree on is the title of worst geological disaster. I believe that title goes to volcanoes while my father believes it goes to earthquakes. This is actually a fun point of contention (For me at least) and is part of a larger passive debate. We haven’t even come close to seeing the worst case scenario for eruptions, in fact we haven’t seen a truly bad case scenario for volcanoes! Think back to all of the most deadly eruptions of the past 100 years, all of those eruptions were 100s, 1,000s, 10,000s, or even 100,000s of times smaller than some of the larger eruptions in recent geological history.
The most violent eruptions of then past 2000 years have grabbed endless amounts of fascination among the geological community. The most violent of which, the Hatepe eruption, hasn’t gotten as much attention as it’s peers. In my opinion, this might be the only historical eruption that rivals the 1883 eruption of Krakatoa’s intensity..This eruption released over 30 km3 of tephra in just 5 minutes and produced the most impressive pyroclastic flows since the Akahoya eruption. The pyroclastic flows traveled 80 km from the volcano, over mountains and across valleys, while traveling at the speed of sound for a significant portion of the flows lifetime. In fact the only reason the flows stopped is because there wasn’t enough material sustain it.
For an eruption smaller than the Tambora this very impressive. We’ve had 3 other “VEI 7s” like this in the past 2000 years and those weren’t as violent as the Hatepe eruption If an eruption like this were to happen in some other volcanoes now, millions would die if the proper preparations weren’t made. In fact, the way that people have been talking about historical eruptions has led to a huge misunderstanding about large eruptions. When people talk about eruptions like Tambora that are considered “VEI 7s” they automatically assume that they are just grade below the biggest eruptions of all time. After all, F4 tornadoes can be just a cut below f5 tornadoes and it’s same with hurricanes. We need to get some facts straight. Human society has not survived a VEI 7 let alone VEI 8. But Tallis! What about Tambora? I hear you say and I’ll say that wasn’t a VEI 7 either, at least not by the standards that other eruptions have to live up to. When most scientists judge larger eruptions, they use Dense Rock equivalency which is very different than bulk. DRE is for how much real magma is erupted while bulk is for the general erupted products. For all the smaller eruptions, bulk is used and for larger eruptions, DRE is used. This has led to a huge misunderstanding for just how powerful eruptions can get. For all of our historical “VEI 7s’ ‘ we’ve used bulk and if we were to use DRE, we’d no longer have any historical VEI 7s. Tambora, probably the largest eruption in history, just produced 46 km3 DRE of magma. Yes, this 30,000 megaton eruption is incredibly not that big in the slightest.
The Los chocoyos eruption, a real VEI 7, produced over 300 km3 DRE of magma, perfectly encapsulates the power that geologically frequent events can actually have. This eruption was around 6 times larger than the Tambora eruption making this a VEI 8 in bulk. This eruption produced pyroclastic flows that traveled 130 km away from the volcano at the minimum, dumped a few centimeters of ashfall 2,000 km away from the volcano in Florida. This eruption likely produced a cooling event in the range of 5-8 C and caused significant Ozone destruction. It cannot be understated how apocalyptic the damage an event like this would cause to our society and that’s not even the scary part! The scary part is the fact that there are eruptions that are up to 15 times bigger than the Los Chocoyos eruption.
Using bulk, we find that Toba and Yellowstone weren’t low-end VEI 8s, they were high end VEI 8s, and as it turns out VEI 9s are real too. Wah Wah springs and Fish Canyon were both over 130 times and 17 times larger than the Tambora eruption and the Los Chocoyos eruption respectively. This puts the energy of the largest eruptions that we know of around 4 Teratons of TNT, much more powerful than what is usually assumed. Unfortunately these eruptions happened so long ago it is almost impossible to give a detailed analysis or timeline. So one’s imagination could run wild concerning how destructive this event would be.
Massive eruptions are much more common than previously assumed, We’ve had 6 VEI 8s in bulk in the past 100,00 years (Toba, Los Chocoyos, Aso-4, Oruanui eruption, AT eruption, Akahoya eruption) The Akahoya eruption released 500 km3 of magma making it over 10x larger than Tambora as well. Actually good news for Humanity but bad news for society.
The question is how would our society react to a VSI 12? (See the link for the definition.) I think now we actually have a much clearer idea of how the world would react, now that we are currently in the midst of a global crisis as well. The COVID-19 pandemic is the world’s first substantial crisis since the cold war and HIV/AIDs pandemic, it is also the first major respiratory pandemic since the Hong Kong flu in the 60s. Contrary to popular opinion, this pandemic is not that special when you look at the numbers. After you adjust for population growth, with a fatality rate of 0.5% Covid-19 has so far been no deadlier than the several other major flu pandemics and it’s almost nothing compared to the Spanish flu which killed between 1% and 5% of the world’s population at the time. A pandemic and volcanic eruption are two completely different things but both are global crises and just like we are unprepared for a major volcanic eruption, we were also unprepared for Covid-19.
People don’t understand just how fragile our modern society is, this pandemic has dealt the economy a damaging blow, millions were put and are currently out of work, causing disrupting global supply chains and trade. This has led to global inflation which has caused a worldwide economic crisis. If this pandemic happened 200 years ago society would’ve carried on like nothing happened, and if it happened 50 years ago, it would’ve caused issues but not to this extent. Our complex system isn’t built to withstand disruptions of any kind and large volcanic eruption is one of the biggest disruptions that society can experience.
People also don’t understand just how high the chances are for a destructive eruption and just how many volcanoes threaten millions. A massive volcanic eruption is infinitely more likely than an asteroid impact, Gamma-ray burst, or other frequently talked about global disasters. There have been 11 major eruptions that were a low-grade VEI 7 or a high-end VEI 6 in the past 2000 years. Giving this year a 1 in 181 chance of receiving a major eruption. For what would be a major global disaster, those are some pretty high odds.
There are several VSI 12 candidates that some others and I have already written about, such as Tatun, Campi flegrei, Aso, Toba! But there’s more! There is so much more it’s actually pretty terrifying and exciting. Here’s a quick list of VSI 12 candidates ranked in no particular order and unfortunately I can’t give too much detail.
- Tatun Volcanic group, Taiwan
Coatepeque, El Savador
Ilopango, El Savador
Campi Flegrei, Italy
Nevado Del Toluca, Mexico
Paektu, North Korea
- Los Humeros, Mexico
These are just the volcanoes I can remember off the top of my head and all of these can threaten millions with a VEI 6 eruption. To give further perspective on how bad volcanic eruption can be, if the Coatepeque caldera produced an eruption like the Hatepe event, almost all of El Salvador would be completely destroyed by PDCs. No other geological disaster can produce the damage a volcanic eruption can. We’ve already seen some worst case scenarios for earthquakes in the 2011 Tohoku earthquake and 2004 Indian Ocean earthquake and while I am not trying to diminish these events, an earthquake can not cause the same damage a volcano can.
Let’s take Corbetti for example, If the volcano were to produce an eruption the size of the Los Chocoyos eruption, over 10,000,000 people would die directly without adequate preparations, the economy of Ethiopia and East Africa would be immediately crippled as the ash fall would cripple transportation and infrastructure and the entire region would be in immediate risk of societal breakdown leading to the deaths of millions more. All of this would happen in just a couple of weeks and it would just be the beginning.
This pandemic has shown us one thing, a global disaster doesn’t have to do that much direct damage to be disruptive, people just have to believe it is. No past pandemic has caused this much damage to the economy and this pandemic isn’t that much worse than other past pandemics. With a massive eruption, the entire global economy would collapse before a single aerosol would form. If Corbetti produced a major eruption, the news of the volcano killing over 10 million people and the fear of volcanic winter would cause global panic the likes of which none of us would have ever seen. Global stock markets would all collapse completely, destroying companies and a large amount of wealth. Global trade would be crushed as every country would try to hastily prepare, leading to countries hoarding it’s resources and/or trying to take others by force. This would cause global food and gas prices to skyrocket making them far too expensive for the common man. This would lead to massive riots and unrest that would cripple preparations and the economy further. Most people would be homeless and unemployed before the volcanic winter actually hit. This isn’t to say that there is nothing that can be done, if the world came with a good global plan to withstand a large eruption and stuck to it, I do believe society could withstand a lower end VEI 8 eruption. I wouldn’t bet money on the world banding together to prepare for it though.
One thing you may have noticed about me is that I am a contrarian; as some edgy teenagers would put it, I don’t like following others. When I read the NDVP and saw the volcanoes on the list, I was impressed by the articles and the selection but I felt as if there were some missing candidates. This feeling is what lead me to research Tatun but one candidate that can’t be ignored on any list is Taal. All of last year, I was screaming my frustration that Taal was a side piece for the eruption in Iceland despite the increasing likelihood of a major eruption. Let us not forget the escalating activity at Taal, the incredible gas emissions, the phteaomagmatic bursts, and the incredible deformation.
As I have been saying constantly, the deformation at Taal is impressive, everything within 30km west of the volcano is inflating, while everything within 20 km southeast is deflating. This is a massive area, over 1,500 km2, the volcano is having a hard time getting magma out of it’s system and that’s a problem.
I’ve had enough of people saying absurd things about Taal, questioning the existence of it’s large magma reservoir and it’s explosivity. Let’s get some facts straight. This a caldera system, formed by large eruptions 140,000-5,800 years ago and for the past 5,800 years the volcano has been chugging out mafic products and smaller eruptions. The fact that this change in behavior is used to say that Taal is no longer capable of VE 6+ large eruptions, felsic eruptions, or doesn’t have large magma chambers is ridiculous.
Healthy calderas produce mafic eruptions all the time, a frequent cause for large silic systems is in fact, mafic magma melting the surrounding crust creating a felsic reservoir but sometimes that basaltic magma doesn’t want to change and it decides to erupt. Mafic products exist at Corbetti, Taupo, Toba, and MANY more. With Taal, there is no reason to assume that this volcano has done a complete flip in it’s volcanism, after so many large felsic eruptions, the volcano has been and is likely still in a recovery stage where it’s building silicic magma and erupting some basalt.
Sillic system don’t die like this, they don’t exist and erupt for over 100,000 years and become a small mafic system. Even if Taal exhausted all of its silicic magma and could only erupt and produce basalt there would still be the ineruptible crystal rich mash leftover, mingling with the basaltic magma that’s trying to erupt. This mush isn’t going to disappear and there should still be some at Taal even if one wants to believe that this a completely mafic system.
People need to understand that the postulated idea of small shallow magma chamber as the source of Taal ‘s recent eruptions makes no damn sense, a 2 km radius magma chamber isn’t going to produce repeat VEI 4s and large dikes; Large sillic chambers don’t just disappear without leaving a trace underground. These are facts.
It’s more likely that this volcano has a large magma chamber than not, the low-velocity zone just north of the volcano is a good candidate but there hasn’t been enough research into it. This shows one of the stupidest parts of human nature. Something that I’ll call “Peachy Bias.”. We’ve ripped on people for their irrational fear of certain events but there hasn’t been enough ripping on people that dismiss the threats that come with living in this world. The damage from the Japanese earthquake and tsunami could’ve been avoided if the Japanese government listened to a man named Ryohei Morimoto. This man predicted the worst affected area by the tsunami by looking at the evidence from past tsunamis. No one listened to him and then Fukushima happened. I love his quote “Even if they couldn’t predict the size of the tsunami, they should’ve been prepared for the waves of the past.”
Look at interviews after disasters, “I never thought this would happen.” “It’s so shocking.” “I didn’t have a plan.” “I couldn’t prepare.” are phrases you might hear. Despite living in tornado country, seeing other areas get hit by major tornadoes, you’ll still see people get surprised when they get hit by a tornado. It’s human nature to dismiss events that seem unlikely to happen and people believe in comforting thoughts and thinking about future catastrophes isn’t a comforting thought for most. Peachy Bias has cost the lives of hundreds of millions and is infinitely more dangerous than its counterpart. I can see a lot of peachy bias with Tatun. Despite a surplus of studies concerning it’s size and history and with 2 nuclear facilities near the volcano, the volcano is considered extinct by some and is completely unknown by others.
This what would make a VSI 12, thinking that Tatun is dead, Taal is incapable of producing a felsic eruption, or that some other volcano will stay dormant are the type of mindsets that precede disaster, volcanoes can erupt just as easily as they can stay asleep and to not have a plan is ridiculous.