Planning for the next Vesuvius eruption

July 29, 2015 10:53 PM

This Italian giant is nestled in the sprawling metropolitan area of Naples, population 3.1 million. We’re not talking “nearby” like Rainier is to Seattle or Popocatépetl to Mexico City. We’re talking a volcano smack in the middle of the city. It is merely ~12 km (~7.5 miles) from the summit craters at Vesuvius to downtown Naples. For your average pyroclastic flow from a volcano like Vesuvius, that is a trip that would take only about two and a half minutes.

The World’s Most Dangerous Volcano May Kill Another City
posted by Spinda (45 comments total)

Will it create the Pompeii and Herculaneum of 3000 AD?
posted by Harald74 at 11:13 PM on July 29, 2015

I'm a bit surprised any scientist is willing to work with civic leaders anymore in Italy. Weren't several scientists arrested for not predicting the last big earthquake they had?
posted by Brocktoon at 11:22 PM on July 29, 2015 [12 favorites]

On the plus side, when they clean up all that debris from the city after the next eruption, maybe they can also collect all that garbage piling up in the streets.
posted by sour cream at 12:03 AM on July 30, 2015

I grew up in an isolated country house built on a hill and, when I was relatively young, one of the "neighbours" (it took about 3 minutes at a flat out run to reach his place) mentioned that there was a dormant volcano nearby. The idea of an eruption immediately took hold of my imagination and nightmares. I spent a lot of time looking out windows and trying to determine probable paths for lava flow. The nights the fog/clouds socked in were the worst, because they completely eradicated the lights from the town below.
posted by Maugrim at 12:24 AM on July 30, 2015 [6 favorites]

Maugrim, lava isn't usually a problem. Sure, it runs like water near the top of a shield volcano (like Mauna Loa), but after it has a chance to cool it slows to a crawl, like inches per minute. You can outwalk it. (But you can't stop it, and it will destroy everything in its path that can't move out of the way.)

What you really want to fear are pyroclastics, because those can move at speeds rivaling a jet aircraft (up to 450 MPH). And unfortunately, Vesuvius produces pyroclastics.
posted by Chocolate Pickle at 12:42 AM on July 30, 2015 [6 favorites]

Being prepared for that next eruption is the key from making the world’s most dangerous volcano into the deadliest.

Wot?
posted by lollusc at 12:54 AM on July 30, 2015 [5 favorites]

(But you can't stop it, and it will destroy everything in its path that can't move out of the way.)

You say! Why should I trust you over Tommy Lee Jones?
posted by biffa at 1:01 AM on July 30, 2015 [5 favorites]

The ever-wonderful Volcano Cafe has lots more on this, a couple of excellent articles are:

Monte Somma and Vesuvius (The world's most ill-begotten piece of real estate - part 2)

Deadly Allure - Mount Vesuvius in Paintings
posted by protorp at 1:16 AM on July 30, 2015 [5 favorites]

I'm a bit surprised any scientist is willing to work with civic leaders anymore in Italy. Weren't several scientists arrested for not predicting the last big earthquake they had?

It made for good sensational headlines, but the trial wasn't about predicting the earthquake. The 7 people implicated were on what translates loosely to "Great Risks Committee"; the accusation of manslaughter was based on their downplaying of the potential risks to the public. Six of them have been acquitted upon appeals; the 7th had his sentence reduced (he had literally said that the seismic swarm people had been feeling for months presented "No danger").
posted by romakimmy at 1:34 AM on July 30, 2015 [12 favorites]

Yeah, no kidding, I've felt like Popocatepetl is uncomfortably close here, but Naples is just nuts. I hadn't realized how close Vesuvius was to the city.
posted by Joakim Ziegler at 1:39 AM on July 30, 2015

I was there recently. It was interesting that from Pompeii you see Vesuvius as a huge, looming volcano really close by and think it's a mad place to build a city (if you knew that was a volcano) but, in contrast, from the top of Vesuvius you can't really see Pompeii at all - you have to look really hard, and know where to look, and you can just about spot it in the vast landscape, so it seems like a really low risk thing and incredibly bad luck that it happened to be struck by the eruption.

The really scary thing, though, is that the landscape you're trying to spot Pompeii in is now just a sea of urbanisation in every direction, from coast to horizon, all around the volcano. Being struck by the eruption has changed from incredibly bad luck to an absolute certainty.
posted by merlynkline at 2:46 AM on July 30, 2015 [4 favorites]

Thank you romakimmy for the much needed clarification on that. There was a lot of skewed/sensational reporting on that issue indeed.
posted by bitteschoen at 3:23 AM on July 30, 2015 [2 favorites]

I grew up in an isolated country house built on a hill and, when I was relatively young, one of the "neighbours" (it took about 3 minutes at a flat out run to reach his place) mentioned that there was a dormant volcano nearby. The idea of an eruption immediately took hold of my imagination and nightmares.

I would suggest you never move to Auckland in New Zealand because it's built all over a whole field of dormant (not extinct) volcanoes.

The main reason why the various volcano eruptions in NZ in times past never killed huge numbers of people is just that there weren't very many people there (still aren't really). The big ones didn't tend to leave large mountains because they were so explosive, just left a hole in the ground instead (e.g. Lake Taupo). So I'm weirdly predisposed to think that big cones like Vesuvius aren't that scary.
posted by shelleycat at 3:35 AM on July 30, 2015 [2 favorites]

The preparations described seem to be all about emergency evacuation. but wouldn't it be good to have a long-term policy of depopulating the worst affected areas? I know that would be difficult and costly and need determined leadership - but even if you did it really slowly it might help (and who knows, the volcano might give you a couple of centuries to get it done).

If there had been a post-war policy making the place a national park where you couldn't build, the problem would never have got so bad.
posted by Segundus at 4:33 AM on July 30, 2015 [2 favorites]

The main reason why the various volcano eruptions in NZ in times past never killed huge numbers of people is just that there weren't very many people there (still aren't really). The big ones didn't tend to leave large mountains because they were so explosive, just left a hole in the ground instead (e.g. Lake Taupo). So I'm weirdly predisposed to think that big cones like Vesuvius aren't that scary.

Yeah, then there are the ones that leave a shattered remnant of what was probably once a perfect Mt Fuji-like cone in their wake, like Ruapehu. "What do you mean, half a volcano?"
posted by Sonny Jim at 4:57 AM on July 30, 2015 [1 favorite]

I know that would be difficult and costly and need determined leadership

Or, as we say in politics, "impossible."
posted by GenjiandProust at 5:38 AM on July 30, 2015 [10 favorites]

The ever-wonderful Volcano Cafe

The blog I never knew I needed!
posted by lollymccatburglar at 5:38 AM on July 30, 2015

but wouldn't it be good to have a long-term policy of depopulating the worst affected areas? I know that would be difficult and costly and need determined leadership

Eh, you mean Naples, right? a historic unique city in the world, on a bay that’s one of the most beautiful, with islands like Capri and Ischia, millions of people living in the area since generations, strongly attached to the place and its culture and everyting that makes a place a place?

It’s like wondering, oh wouldn’t it be good to move San Francisco to a less dangerous non-earthquake area!

How does that sound? doesn’t it sound like an ever crazier idea than the idea of living below a volcano? (or on earth that’s prone to shake for the big one any minute)
posted by bitteschoen at 5:40 AM on July 30, 2015 [11 favorites]

The other issue is that volcanic ash generally makes for lovely fertile soil, so living near volcanoes is attractive from that angle too.
posted by shelleycat at 5:46 AM on July 30, 2015 [3 favorites]

Generally I'm one to nod my head along with Nietzche whenever he gets going on one of those barnburners but yeah, 'Build your cities on the slopes of Vesuvius!' has always jumped out at me.

No. Don't do that, generally speaking. Unless you like rebuilding your cities somewhere else years later and settling up all the Volcanism insurance claims.
posted by mrdaneri at 5:59 AM on July 30, 2015

Don't forget Quito.
posted by lagomorphius at 6:05 AM on July 30, 2015

Echoing bitteschoen; you're talking about the 9th most populous urban area in the EU, and one which has had urban settlement since sometime in the 2nd millenium BC. Its inhabitants are renowned for an intense streak of disregard for authority; it's a thriving, wild, vibrant, sometimes scary place... more akin in some ways to Cairo or Mumbai than to any other major European city.

Naples, its bay and the wider Campanian area are incredible, I would urge anyone who has the chance to visit to seize the opportunity. Just brace yourself before tackling downtown Naples itself.
posted by protorp at 6:06 AM on July 30, 2015 [3 favorites]

Favorite Naples tale:

Naples in the Time of Cholera, 1884-1911
Frank Snowden

It's also episode nine of his Yale course on Epidemics western civ since 1600.

Apparently the city was infected at pandemic level and the Be Powers censored all news of it to keep tourist income from cratering.
posted by bukvich at 6:22 AM on July 30, 2015 [9 favorites]

(But you can't stop it, and it will destroy everything in its path that can't move out of the way.)

Ah, but they did control where it went in Iceland in 1973.
posted by Paid In Full at 6:31 AM on July 30, 2015 [4 favorites]

And in addition to our recently celebrated seismic risk, if a couple trees and a recently built house came down, I wager I could see an Rainier from my bedroom window here in Seattle. Ranier has erupted as recently as the 1890s, and it makes pyroclastic flows and mud flows called lahars. Those make it all the way to the Puget Sound every 500-1000 years, across an area now inhabited by 80,000 people.

The mountain is gorgeous though.
posted by wotsac at 6:32 AM on July 30, 2015

As a Seattleite, I take comfort that a Big One from Rainier will likely wipe out Tacoma, while we remain upwind and far from any mudflows.

Rainier, like Mt St Helens and Mt Lassen, tends to explode, collapse, and throw hot boulders and ashbombs. It's the steam/water/ash/mudflow down valleys, not lava, that's the danger. Also inundating I-5, Union-Pacific Santa Fe and Amtrak railroads, and some hydropower and water supplies. Ash will shut down airports for quite a while. But hey, ferries should be fine if their engine airfilters can handle the ash.
posted by Dreidl at 6:43 AM on July 30, 2015 [4 favorites]

It's also episode nine yt of his Yale course on Epidemics western civ since 1600.

Oh my gosh, things that I didn't know existed that I must now watch immediately.

The thing is, a whole lot of cities are sitting on ticking time bombs. My brother, who lives in Tokyo, says that basically the whole city was thrown up in a hurry with very little regard for building codes, because pretty much everything was destroyed during World War II, and the next time there's a really big earthquake, tens of thousands of people, at least, are going to die. (And I mean, there's historical precedent.) We all know that Seattle is doomed, because the New Yorker told us so. New Yorkers had better not get too smug, because their city is going to be underwater in a hundred years. There are a lot of people on the earth now, and there aren't a lot of spots that are immune to catastrophic natural disasters. If we didn't build cities on any of them, there wouldn't be a lot of places to put us all.
posted by ArbitraryAndCapricious at 6:49 AM on July 30, 2015 [4 favorites]

And one other thing; Portland, OR has multiple small volcano ash cones inside the city limits. Mt Tabor was still venting steam when I moved there in the late 80s. There's now a Nike-sponsored basketball court in the lower crater, but more vitally, several water reservoirs, a christian college, and some of Portlands most historic homes on the slopes.
However, a big earthquake or Columbia/Willamette River flood is of much more concern amd recent planning.
posted by Dreidl at 6:52 AM on July 30, 2015 [1 favorite]

I used to think "Haha I don't live near any earthquake zones, coasts that will flood, or volcanoes!" then I read about the Yellowstone supervolcano and had to just throw up my hands. No place on earth is entirely safe from natural disaster. And if it was, then you could worry about meteorites.

I still wouldn't live on Vesuvius, though. Lot of people are going to die when that sucker goes.
posted by emjaybee at 7:00 AM on July 30, 2015 [1 favorite]

I spent some time in the area a few years ago, doing an archaeology program (discussed a bit on MeFi here). It was absolutely fascinating. I say often that Pompei (the modern city), Naples, and the surround remind me of nothing so much as New Orleans. Same chaos, same devotion to incredibly good food and local culture, same shrugging fatalism. Our group received a "safety talk" while there about potential eruptions, which amounted to 'place your head between your knees and kiss your ass goodbye.' There is an evacuation plan, but it's abundantly clear it would never get even half the population out even if it worked perfectly, which it wouldn't because it's Naples.

Being struck by the eruption has changed from incredibly bad luck to an absolute certainty.

A lot of who gets it depends on geography, the force of the eruption, and what the winds are doing. As someone mentioned above, it isn't lava flow - it's enormous, mile-wide clouds of gas, rock, ash tiny particles of dust that blots out the sun, buries everything in sight, and turns into a cementlike glue in the mucous membranes and lungs, gradually making it impossible to breathe. Pompeii happened to be right under the falling debris cloud. Herculaneum, though, only got a little dusting of volcanic ash during the first days, but after the heat and force of the eruption cooled, the cloud of matter in the sky cooled, collapsed, hit the earth, and roared down the slopes in a tsunami of debris, heat, and mud called a pyroclastic surge which buried everybody within seconds. The different local effects of the volcano are also part of the reason why Herculaneum is the better preserved site.

No. Don't do that, generally speaking. Unless you like rebuilding your cities somewhere else years later and settling up all the Volcanism insurance claims.

It's one of those things that seems to make so much sense: just don't do it. But yeah, this area has been a seaside resort since prehistory. It's stunningly beautiful. The volcanic soil is amazingly fertile, and the warm, mineral-rich oceans teem with seafood, producing a food culture worthy of world heritage designation. It's a massive economic and tourism engine for a country that survives largely on tourism. And it's been people's homes for generations upon generations. It's a vast and important area and not one likely to make an easy transition into a national park via some Italian form of eminent domain. It's amazing to walk and drive around there now - there are places where there are steam vents on the mountains, and you see the vapor puffing out. Makes you think. But when you take the long view of the risk, it's really one generation that pays the price, while dozens of generations reap the rewards of living and working in this unique and strikingly gorgeous ancient region. Ultimately, humanity gains. Even after the eruption of 79 AD, people were resettling on the volcanic slopes within a couple of decades. It was great land.
posted by Miko at 7:21 AM on July 30, 2015 [14 favorites]

> I hadn't realized how close Vesuvius was to the city.

It didn't use to be so much. Then they expanded the city right up the side of the mountain.
posted by jfuller at 7:33 AM on July 30, 2015

Though there have long been settlements all over the sides of the volcano - for centuries. They essentially just became denser and linked together.
posted by Miko at 7:48 AM on July 30, 2015

>Mt Tabor was still venting steam when I moved there in the late 80s.

I would love to hear which '80s you are referring to, since as far as I know the Boring lava field hasn't been active for 300,000 years! Perhaps you're thinking of Mt. St. Helens?
posted by Secretariat at 8:06 AM on July 30, 2015

Eh, you mean Naples, right? a historic unique city in the world, on a bay that’s one of the most beautiful, with islands like Capri and Ischia, millions of people living in the area since generations, strongly attached to the place and its culture and everyting that makes a place a place?

Yes, the bay's nice, but I'm not talking about moving that. Nor about the historic centre, nor even about all the notorious shithole slums necessarily: just the most threatened parts of the bits built since 1944.
posted by Segundus at 8:09 AM on July 30, 2015

the most threatened parts of the bits

That's the entire region. Bay and islands included. That's what I was trying to say above. Destruction will not be localized and is somewhat unpredictable.
posted by Miko at 8:36 AM on July 30, 2015 [1 favorite]

Nope, little teeny 660' Mt Tabor has steamed (occasionally) within living memory. What I saw was about equivalent to a cup of hot tea, but it went on as long as I watched it, and after I came back down the hill an hour later. Early summer, before noon - not the conditions for ground fog or breath steam. The locals I was with didn't seem surprised, they had seen it before.

There is still modest hydrothermal activity in the Columbia Basin, with associated tiny earthquakes. Maybe from the Juan de Fuca subduction zone? I'm told Tabor steamed a bit more as St. Helens became active, and for some years after the major eruption. I saw the steam about 12 years after the St Helens event.

St Helens erupted 2004-2008? I haven't heard of Tabor doing a thing.
posted by Dreidl at 10:07 AM on July 30, 2015

FYI - That Volcano Cafe blog is pretty awesome, but it seems from the comments that it's been hijacked and they're starting over at http://www.volcanocafe.org
posted by romakimmy at 11:23 AM on July 30, 2015

> That's the entire region. Bay and islands included. That's what I was trying to say above.
> Destruction will not be localized and is somewhat unpredictable.

There could, for instance, be an eruption with just smoke, steam, and some lava, like your typical Mauna Loa event that makes pretty pix for National Geographic. Or an eruption with major pyroclastic flow, which they now say is what did it for Pompeii and Herculaneum more than ash suffocation did. Or Vesuvius could pull a Mount St. Helens and explode most of itself (and anything unfortunate enough to be anywhere in the neighborhood) off the face of the earth all at once. (Cue earth-shattering KA-BOOM.) Cloudy crystal ball department, though at least you can't blame Vesuvius for that.
posted by jfuller at 11:28 AM on July 30, 2015

It was interesting that from Pompeii you see Vesuvius as a huge, looming volcano really close by and think it's a mad place to build a city

The Romans at least didn't know it was a volcano. A contemporary fresco shows a sharp pointy vine covered mountain, a perfect complement to that really world class bay.
posted by BWA at 12:35 PM on July 30, 2015

What would happen if Mount Vesuvius erupted today?

Beginning in 2004, the government also set up a program to pay people $46,000 (30,000E) to relocate outside of the zone -- though it has had relatively few takers.

Experts warn that emergency plans should also include nearby Naples since an explosion could send dangerous burning ash and pumice as far as 12 miles (20 kilometers) [source: Fraser].... scientists expect that the next eruption will be an incredibly forceful explosion, termed plinean, marked by flying rock and ash at speeds of up to almost 100 miles per hour (160 kph).
posted by Miko at 12:56 PM on July 30, 2015

> Being prepared for that next eruption is the key from making the world’s most dangerous volcano into the deadliest.

Wot?

You know, this surprised me too! Here's what I think is happening: "the key to X" has come unmoored from its roots as a physical metaphor, allowing the development of "the key from X" as an opposite (parallel to "road to/from X", say).

Key to X: phenomenon sufficient (and probably necessary) for X to occur
Key from X: phenomenon sufficient (and probably necessary) for the prevention of X
posted by No-sword at 5:01 PM on July 30, 2015 [1 favorite]

Boy, this really adds another layer to the old saying "vedi Napoli e poi muori" (see Naples and then [you can] die)!
posted by MsMolly at 5:07 PM on July 30, 2015 [2 favorites]

If you've gotta go, I can think of many worse places to check out from.
posted by Miko at 12:39 PM on July 31, 2015

bukvich: Frank Snowden (formerly Jr) was my PhD committee chair, and an incredibly nice man. Great to hear the love for Naples in the Time of Cholera, part of the 1980s/1990s trend for naming historical works on disease after novels that included that disease (cf Death in Hamburg/Death in Venice).
posted by Vcholerae at 2:33 AM on August 1, 2015

shelleycat: "The other issue is that volcanic ash generally makes for lovely fertile soil, so living near volcanoes is attractive from that angle too."

According to the Volcano Cafe article:

Vesuvius today is rapidly getting known as the Garbage Dump of Italy. This is due to a large amount of both legal and illegal dumping of garbage and industrial waste in old flanking vents and cones. This has raised the toxicity around the volcano to a level where one should not eat anything growing on or around the volcano. Even the fabled wines of Vesuvius are now deemed not fit for human consumption. It is sad that Man’s folly is destroying one of the world’s most beautiful vistas.

posted by Chrysostom at 5:30 PM on August 5, 2015