When Pinatubo turned the tide

The sea is our fascination. We go out of our ways to find it, and it is where we go for holidays, spending our time lying on the beach. Close to half the world’s population lives within 100 kilometers of the coast. For those who live here, there is a good living to be had, either from farming the fertile river deltas or by harvesting the bounty of the sea itself. For a species that originated on the African savannah, our affinity to the oceans is quite remarkable. There is a tide in the affairs of men, as Shakespeare wrote.

But the sea is an inconstant neighbour, hard to pin down and impossible to contain. It rises and falls, with the waves, the tides, and the storm surges. And its onslaught comes with immense power. Living near the coast involves risk. Some people live behind natural defences, such as the sand dunes. Others build their own defences, living behind man-made barriers. And sometimes, there is little choice but to move house. All’s well that ends well, Shakespeare claimed. But in the end, the sea always wins.

The pillars of Pozzuoli

The most extreme case of sea level changes around our cities comes from Naples. Three marble pillars stand on the ruin of an old Roman square, close to sea level. When the pillars were build, they were smooth. But now, their remains show strange marks. The pillars are about 14 meters tall. The bottom 3.5 meters of the pillars are smooth. Above this there is a pock-marked layer, also about 3.5 meter deep. And above that the pillars return to being smooth.

The solution to this conundrum has been known for over 200 years. The scarred surface suffered the attention of a boring mollusc: some of the holes still have remains of the bivalve attached. But this mollusc does not live at height. When it grew on the pillars, the pillars must have been under water for it to flourish. The sea here must have reached at least seven meters above its current level. Why the smooth area at the bottom of the pillars? The best explanation is that this part was covered by rubble or sediment. The sea itself has not risen (and subsequently withdrawn) by that much. Instead, it was the land that changed. The cause is bradyseism, where water circulating underground causes periodic inflation and deflation. It happens inside large calderas – and there is a massive one here. Imagine how the people would have responded to seeing the sea approach! The area was quickly abandoned. We don’t quite know when.

And the land here is still moving. The harbour has been rising, bad news for boats and it beats the purpose of a harbour. A new set of mooring points had to be built, well below the old ones. In Naples, change is constant.

Where once boats were moored, now cars are parked at the harbour of Pozzuoli. Source: https://uwaterloo.ca/wat-on-earth/news/visit-temple-serapsis-pozzuoli

Bradyseism occurs in a few other volcanic regions. A similar, more widespread problem happens in build-up areas where too much water is being pumped from the ground, causing the land to subside. Subsidence can be problematic when the land is already close to sea level (or river level) to begin with, as is the case in many of world’s major cities. Examples of cities with increasing flood risks due to (probably) self-inflicted subsidence include Djakarta and New Orleans.

Sea level rise in different regions, based on tide gauge records. The values include the ‘global isostatic adjustment’, that is the local rise or subsidence due to recovery from the ice ages. Figure from the IPCC, 2013. Click on figure for higher resolution.

But now there is a new change. And it is not the land, but the sea itself which is changing. Sea levels have started to creep up, worldwide. The amounts are still small: over the past 25 years, the sea has come up by about 7 centimeters (or 3 inches, for those less metrically inclined). The reason is well known: melting glaciers are adding their water to the oceans. In addition, those oceans are warming – and warm water expands. For the oceans, the only way is up. We improved our standards of living with the best of intentions: better lives for all people is a admirable goal, and is perhaps underused as political slogan. But the way we went about it is now producing unintended side effects. We need to better understand what is happening, how it is happening, and where things are going: otherwise we are shaping the future with our eyes closed. Good intentions are not enough. As Shakespeare warned: Some rise by sin, and some by virtue fall.

The data shows that the sea level rise began in earnest around 1900. The IPCC finds that the rise was around 1.5 mm per year early in the century, increasing to around 2 mm per year around 1990 and 3 mm per year by 2010. The total change so far has been some 20 centimeter. The models predict that this acceleration will continue, although with large uncertainties. Sea levels may rise by anywhere between 40 cm and 1 meter by the year 2100. Beyond that, the only certainty is that the rise will become larger. The last time temperatures were at current levels, in a previous interglacial, the sea topped out at 4 to 9 meters above the current levels. The situation is not identical to that time, and we shouldn’t expect identical sea levels, but the warning is there. It is important to get the models right, to know what to prepare for.

And not all of the data is understood. Over the past 25 years, the rate of sea level rise has fluctuated, and the reason for this was not clear. It left an uncertainty over the projections for the future. But now it appears that this problem has finally been solved. And the culprit is an unexpected one: the finger is pointing at a volcano. The cause was Pinatubo.

To pin the sea

Measuring sea level is not easy. The water level is constantly changing, minute to minute, hour to hour, even month to month. And an instrument to measure sea level needs a solid surface for its mounting, something not fully compatible with the ocean. It needs, in the words of Shakespeare, One foot in sea, and one on shore.

The oldest records are from Europe, starting in 1700, first in Amsterdam and shortly after measurements also began in a few other cities. The Stockholm data set has been most useful: there, sea level rise started early, in the 19th century, and accelerated during the 20th century.

A tide staff in Glacier Bay, Alaska, 2010 (NOAA Photo Library)

In the US, regular sea level measurements started after 1800. The first instrument used was a tide staff, mounted in sometimes inconvenient locations, if possible isolated from waves, and read off manually. Later, a float was used, with a pen attached which scratched a rotating drum, covered with paper. This removed the need for manual reading: now it was only necessary to collect and change the paper.

The next step came in 1993, when satellite measurements began. This opened up the world of the sea: no longer were measurements limited to a few coastal locations. Satellites don’t cover the polar regions well, but elsewhere their coverage is much more widespread than coastal gauges could ever give. The data that we have from 1993 onward is superior to the older data.

But even with satellites, the measurements are not easy. The required accuracy is better than a centimetre, while using a radar mounted on a box that is moving at several kilometres per second, a few hundred kilometres up. The radar signal comes back in about one millisecond, and this return time needs to be measured to an accuracy of a tenth of a nanosecond. The amount of water in the atmosphere affects the travel time, so the satellite measures the water vapour separately. Even the time it takes the signal to get from the receiver to the detector counts, and over the years this electronics can age. Each satellite has internal calibration systems, and there are several different satellites which allows for some cross-calibration. Finally, the location of the satellite needs to be known to a very high accuracy, using laser ranging and GPS.

The accuracy of the satellite data approaches 1 mm, meeting the requirements for the measurement of sea level rise per year. But there was something funny about the data.

Sea level jitters

Satellite sea level data. Figure from Fasullo et al., Is the detection of accelerated sea level rise imminent? Scientific Reports,  vol. 6, Article number: 31245 (2016). Click on image for full resolution.

The deceleration of the sea level rise. Figure from Cazenave et al. The rate of sea-level rise. Nature Clim. Change 4, 358–361 (2014). Click on image for full resolution.

The satellite measurements showed that the sea level rise in the mid-1990’s was 3.5 mm per year. But in the following decade, it slowed down to 2.7 mm per year, before accelerating again after 2011. This was very strange. The deceleration coincided with something which became known as the ‘pause’: a period during the 2000’s when the Earth seemed to be warming up more slowly than before or after. Explanations were sought: the atmosphere can warm more slowly if the oceans act as a bigger heat sink. The efficacy of the transfer of heat to the oceans can vary, due to the vagaries of the ocean currents and oscillations. But if more heat had been taken up by the ocean, the ocean should have warmed (and thus expand) faster, not slower. This was the opposite to what was seen.

And there was more. The tide gauge measurements from before the satellite era showed a rise of about 2.5 mm per year by the early 1990’s. This was quite a bit less than the satellites found shortly after. After 1993, the tidal gauges and satellites do agree well. It is hard to directly compare the two for a given tide gauge: you would need to be lucky that a satellite crossed directly over the tide gauge, and this is actually unlikely. If you only have a few satellites, you get good global coverage, but not local coverage. But the averages agreed well. It was as if the rate of sea level rise had jumped just when the satellites came on-line.

Church & White, in 2011, were the first to point the finger of suspicion at Pinatubo. It exploded in 1991, shortly before the time when sea level rise suddenly seemed to accelerate. However, they did not have a specific model, just a feeling. The timing seemed right, and it was a large eruption, at least for the 20th century (some other centuries had had much bigger bangs). But could a volcanic eruption really affect sea levels to such an extent? The world’s mine oyster, Pinatubo could have echoed Shakespeare.

Pinatubo in action

Taken by astronauts from the Space Shuttle in early August 1991, this photo of the Earth’s limb shows the double layer of volcanic aerosol particles that spread through the stratosphere following the catastrophic eruption of Mt. Pinatubo. Photo courtesy NASA JSC’s Gateway to Astronaut Photography of the Earth.

Pinatubo was one of the largest eruptions of the 20th century. It was also the first eruption where mass casualties were avoided because of accurate prediction of the eruption, something the USGS can take a lot of credit for. Their scientists rose to the occasion.

On June 15, 1991, 20 million tons of sulfur dioxide and ash exploded into the sky. Some of this made it into the stratosphere, and it stayed around for a year or more. Some remained lower: I remember air plane windows appearing milky white and hard to see through. Lufthansa told us that it was the volcanic sulfur eating into the windows, and that they had to replace the air plane windows far more often than before. The sulfur dixode created a partially opaque layer which intercepted the sun light. Less of the sun filtered down to the surface, and therefore the Earth cooled – a bit. We now know that volcanic ‘winters’ (it actually affects summers more than winters) can last a few years. Pinatubo depressed global temperatures by 0.2-0.5C. By 1994, the Earth had recovered.

But the sea hadn’t. This was unexpected. The sea has a much higher heat capacity than the air, and so it is much harder to change the temperature of the ocean than it is to change the air. Thus, the expectation had been that Pinatubo would have little or no effect on the ocean. Satellite measurements which could have shown better did not start until two years after the eruption. If you can’t measure it, and expect it to be negligible, the tendency is to forget about it. But men are men; the best sometimes forget, Shakespeare wrote.

Figure from Fasullo et al.: Is the detection of accelerated sea level rise imminent? Scientific Reports,  vol. 6, Article number: 31245 (2016). Click on image for higher resolution

Fasullo et al, in 2016, remembered, and took a closer look. The figure here is from their work. The top panel shows the albedo (the fraction of sunlight intercepted by the sulfur droplets) which their model uses to compute the effect on the seas. The model contains three different components.

The first component is that of the cooling caused by Pinatubo. Just like the earth, the sea also received less sunlight. The surface water cooled a bit, and cooler water contracts: the sea level drops. In the model of the bottom panel, this is the red curve, labelled OHC (ocean heat content); it shows an expected 6 mm drop in sea level.

The second effect is indicated by the black line, labelled PW. This is ‘precitable water’ and stands for the amount of water in the atmosphere. Colder air contains less water. As the air cooled, post-Pinatubo, the excess water which no longer cold be held by the atmosphere was returned to the oceans. This caused a slow rise in sea level of about 1 mm, followed by an even slower return to zero as the air temperature recovered from the volcano.

The final effect is the amount of water stored on the continents, in lakes, rivers, ground water, and glaciers (TWS, the green line). This varies a lot from season to season and this variability is included in the model. More terrestrial water means less ocean water. Initially the cooling caused a sea level rise, for the same reason at the PW effect: there was less rain. This amounted to about 1.5 mm. But at later times it caused a fall in sea levels, as the cooler weather allowed more water to be captured by the glaciers.

The blue line in the top panel is the sum of the parts. It shows a drop of 6 mm, beginning to slowly recover after 1995. The available tide gauge data could not have picked up such a signal. It is notable that the sea level drops lagged behind global temperatures, which were largely back to pre-eruption values by 1995. The sea had the longer memory. Doesn’t it always? “The days but newly gone, Whose memory is written on the earth” is perhaps one of Shakespeare’s few mistakes: it is better to enscribe memories in the sea.

The sea level anomaly

This 2016 paper mentions that the Pinatubo effect could indeed have caused the anomalous acceleration of sea levels seen during the 1990’s. Their detailed analysis of this was published only in the past month. It is by the same team, and it is perhaps not entirely clear why the work wasn’t finished in the earlier paper.

Accurate satellite measurements started in 1993. If the models are right, the satellite data began right at the bottom of the Pinatubo drop, the worst possible starting point when sea level was lowered by 5-7 mm. The satellite era measured the recovery from this drop, but attributed all the sea changes to the long-term sea level rise.

Source: Nerem, R., et al. Climate-change–driven accelerated sea-level rise detected in the altimeter era. (2018) PNAS, in press. http://www.pnas.org/content/pnas/early/2018/02/06/1717312115.full.pdf

The figure shows the result of the calculations. The blue line is the satellite data, and it shows the anomalous fast rise up to the early 2000’s, followed by a slower rise, and re-acceleration after about 2009, partly obscured by a short-lived drop in 2011. The red line shows the same data, but now with the Pinatubo effect removed. Effectively, the sum of the three components of the model of Fasullo has been added to the data. The fast initial rise has now disappeared, and the rise remains at a more or less constant rate until 2005 when a slight acceleration sets in, albeit temporarily obscured by the 2008 and 2011 dips. Finally, a model is included for the effect of the ENSO (El Niño-Southern Oscillation)– in effect, this compensates for the El Ninos and La Ninas which also affect sea level. (This last part is the new thing included in this paper – the rest is already in the Fasullo paper.) This correction gives us the green line, which is the final curve for the global long-term sea level rise that they derive. (Green is the colour of jealousy, another association first made by Shakespeare.) The main effect of the ENSO corrections is that it removes the bumps in 1998 and 2016, which coincided with the record El Ninos of those two years. Interestingly, the dip in 2011 is reduced but not fully removed: this had been attributed to a La Nina event but perhaps there was more to it. Whatever it was, it was temporary.

After the Pinatubo effect was accounted for, the sea level rise became smooth, apart from some year-on-year fluctuations. The black line shows the new fit. In the period 1993-2000, it gives a rise of a little over 2 mm per year. This value fits well with that derived from tide gauges in the period before 1993. Problem solved.

The conclusion is that the fast rise seen in the 1990’s, and the subsequent slowing down in the 2000’s, were caused by Pinatubo. Volcanoes don’t just affect the land and air. They suppress the sea as well. Who knew that volcanoes could cause sea-change? Shakespeare foresaw their value for science when he wrote: Suffer a sea-change Into something rich and strange.

Volcanoes and the sea

Was Pinatubo unique? Probably not. The simulated plot shown here suggests that several other volcanoes may have had an impact as well. But one should be careful. There are also decade-long fluctuations which are natural, caused by changing circulations in the oceans. The Agung eruption in the plot has a very long-lasting effect. That is much more likely to trace such a fluctuation. At the current time, sea level is rising so fast that these decadal changes have little impact. In the past it was different, and it is not obvious that volcanic suppression can be distinguished from the effects of changes to ocean circulation.

We can now also look at future projections. The authors find that the sea level rise is accelerating by about 0.8 mm per decade. This is what we need to know in order to calculate how high the sea might get by the end of the century. If only the linear rate of 3.5 mm per year continues to apply, then sea level will get higher by about 30 cm compared to 2015, or 50 cm since the start of the rise around 1900. This is the ‘best case’ scenario, and it would imply that many places could manage but some rich Floridians and some less rich people in Galveston would get wet feet. But with this acceleration term included, it will get wetter: sea level will increase by 50 cm from 2015 levels, or 70 cm in total. Instead of wet feet, people will begin to get wet knees. The numbers fit well with the IPCC projections which were made before this acceleration was measured: the new results exclude the lower values of the IPCC but agree with the likely range.

How high will it go? That is very uncertain. The best estimates are that for every 1C increase in global temperatures, sea level will eventually rise by 1-3 meters. But there is a complicating effect here, because if the Greenland glaciers collapse, the sea will rise by 7 meters just from this. And that is projected to happen if temperatures go up by 2-4C. Such a collapse may take many centuries, though. We should get an inkling in the next two decades: if the observed acceleration accelerates, the likely cause is Greenland and it may be time to cash in on that seaside property. Regardless of whether this happens or not, by the time the next century comes around, the sea will rise by 1cm every year. You would not want to sell flood insurance: every decade will see another previously flood-free area which is flooded following a surge.

I should point out that these are the projections of the models. There is another technique where people look at past correlations between temperatures and sea level, and extrapolate that. Those studies invariably predict larger or faster rises, typically 1 meter or more by the turn of the century. If those calculations are correct, future studies should uncover a faster acceleration. Time will tell – as long we don’t get another Pinatubo playing havoc with the data. Time’s the king of men, and gives them what he will, not what they crave, as Shakespeare said.We need to find the facts, not just hope for the best.

Pinatubo’s legacy

The sand plains left by the Pinatubo lahars

The scars of Pinatubo’s eruption are still there. Where once was the immense Clark air base is now a huge sand plain, left there by the lahars. The Philippines have a unique way to turn disaster into opportunity: the sand is being sold to Singapore for construction. But the sand has also left huge cliffs which are now unstable. According to the local information signs, even a mistimed shout could bring down the walls. The caldera walls are also at risk of collapses. And it will be many years before all the scars have healed.

And now we find that Pinatubo has left scars in our climate record, by suppressing the very sea. It was even responsible for an apparent pause in the sea level rise. When the data becomes sensitive enough, the effect of volcanoes can show up in surprising places. Satellites gave us a vision of Pinatubo’s volcanic sea-change.

Let Shakespeare have the last say, in the words of his Pinatubo of suppressed rage, Hamlet:

to take arms against a sea of troubles
And by exploding, end them.

Albert, March 2018

141 thoughts on “When Pinatubo turned the tide

  1. Great as always Albert! even if I felt I was being force fed some English literature lol

    • True, english literature tends to go down better with force feeding. But the comics should provide some sweetener. And it is amazing how many english expressions (and words) come from Shakespeare. Digested and regurgitated. (Perhaps better stop here.)

      • OT… perhaps someone here can answer a question i’ve often wondered about but have been unable to answer since i only speak english with an understanding of only a smattering of spanish and german and french. Which language has the best poety and which the best literature? Ready, Set, Argue!

        • Perl and it’s cousin PhP, which are both derivatives of C. PhP is a bit better and more nuanced in it’s use. With Perl you sort of have to fight it into compliance for what you are trying to get across. The beauty of Perl is that even though it’s an interpreted language, is nearly as fast as it’s compiled Assembly language equivalent.

          • Cannot agree, Pascal and its derivative Delphi are by some margin the best languages. The only ones where I routinely wrote pages of code with zero errors (after a successful compilation, natch).

          • Well, we are in agreement that the most poetic is a computer interface language. With no experience in those two, I cannot muster an argument against them.

            There are,10 types of people. Those who understand binary, and those who don’t.

            — Izzy

          • @farmeroz: That can’t possibly be correct. Obviously, the best language will belong to the Lisp family of languages, with Haskell perhaps a dark horse candidate (at best). It certainly won’t be an imperative, drudgery-inducingly-manifestly typed overly-syntaxed monstrosity like Delphi. 🙂

        • Japanese might be a contender for best poetry. Some very good poetry in Spanish also.

        • Well, you all are reading the product of PhP coding right now. PhP was designed for bulletin boards and Blogs. It’s the nuts-n-bolts of WordPress. (That or the other cousin, Java)

      • Ok, late Friday for me, but first, great post, Second, my wife was an English Lit. major. Third, I have several Calvin and Hobbs cartoon books (just finished reading them in the “Library” recently). I’ll put up Calvin & Hobbs against English Lit. any time. Carry on… 🙂

        • What about written versus spoken poetry. With both Islamic script and Chinese/Japanese script, the calligraphy itself is art. Of course, there are the illuminated manuscripts of the Middle Ages. English was formed by all the various groups that invaded the islands, Celts, Gauls, various Germanic and Scandinavians, and the Normans, plus English has conscripted great words from all the places the British Empire and traders went. Finally, which dialect of English, various regional British, American, Canadian, Australian, New Zealand, and all the Anglophone countries around the globe. Spoken word poetry will sound different in all of them. Apparently Puskin in Russian is amazing, Pushkin is any other language is meh, ok. English has one of the largest vocabularies of any language, more than half a million words. Shakespeare’s writing has a vocabulary of +30,000 words. The average person’s vocabulary is under 5,000 works. I would argue that the very premise of the question is problematic. Universes of meaning are gained and lost in translation of both language and experience.

          Rescued from the dungeon /admin

  2. Aren’t all the projections of warming effects dependent on explosive volcanism being as piddling in the 21st century as it was in the 20th? Some superstitious Philippinos maintain that God caused Pinatumbo to erupt to destroy the obnoxious American air force base. Perhaps it was actually to confound climate scientists or their employers who were using their predictions to cash in on Enron stock.

    • Don’t forget that all eruptions only have a temporary effect, so long-term projections are largely unaffected.

      • About 2 months to convert SO2 to sulphate and 48 to 50 months for the sulphate to sediment out of the Junge layer. (aka “Aerosol layer”)

      • Just a thought. Comparing apples to sponges. Eruptions are real and have a real effect, if only temporary. Long-term projections are…well, model projections. A real-world event can never have an effect on a model projection.

        • Unless you build a model that updates itself with real world information as it comes in. But then it would affect the next projection.

      • What is “normal” and what is “noise,” that’s the difficult question. What is the optimum climate? That which is/was average once we began making records or what is “adaptable” to for homo sapien sapien and all the species we happened to have categorized? Any new species in a new range of habitat could be called “invasive.” Nature appears to be equal parts creation and destruction, as are we humans, her most precocious offspring.

        Feeling philosophical today.

        Rescued from the dungeon /admin

    • My comment is defunct → please ignore.

      (Deleting it would cause comment flow problems)

  3. In keeping with the Shakespeare theme… A year or so ago, I brewed up a batch of beer using a variation of the formula common at the time for quayside pubs. Barley augmented with oats. One of the most vile beverages I have ever had.

  4. A very scholarly piece of research and fascinating, too. Thank you Albert!

  5. I’m just curious, but you mention 70 cm of sea level rise as the high end worst case scenario, but when I have done research on sea level rise this century, it comes back with 1 meter being a conservative estimate and somewhere between 1.3 and 2.5 meters by 2100 is expected. The only sources suggesting a rise of less than 1 meter are about 5-10 years old and don’t mention thermal expansion of the ocean, only melting of ice which was also not as extreme then as it was this year (allegedly there was open water north of Greenland over this winter…)

    • That is the difference between the full models run by the IPCC, which give the lower rates, and the projection from past relations between sea level and temperatures, which give higher rates. Thermal expansion is included in the full models, by the way.

      • In truth it is probably almost impossible to know how much higher the sea will be in 2100 until it is actually 2100. But the number will probably continue to get higher as time goes on. To be honest I wouldn’t be surprised if the number turns out to be something completely out of what is predicted now. We dont really know how long it actually takes for an ice sheet to collapse and it could be way quicker than we think. If that happens then whatever we predict now is useless. But I am lead to believe that the higher estimates are more likely with the current evidence.

        • We have some idea from what happened in the last ice age. Once the melting began in earnest, sea levels rose by about 1 meter per century over a very long time (10,000 years). At times the rise may have been faster, of course. It is likely that we will have something similar, and less likely that it will be much larger.

          • That holds true as long as we don’t continue using fossil fuels and increasing CO2 emissions. As far as I know and have done research on, the last time there was over 400 ppm of CO2 was in the early pliocene when the sea was well over 20 meters higher and even east Antarctica was mostly ice free. And I think the projection is that over 700 or 800 ppm will exist before the end of this century. The last time that happened there were alligators on the northern coast of Greenland and 15 meter snakes in South America. There were also no polar ice caps at all and hadn’t been for a very long time. So going from an impending ice age to a thermal maximum event within 300 years is something completely out of what we can compare to anything in the fossil record, and as a result I think we might be underestimating the severity of our current situation and how fast it will happen. For all we know the west Antarctic ice sheet could undergo a mass calving event and break up entirely within the next 50 years. Whatever we plan for using our current predictions suddenly becomes a useless effort.

            Sorry if I come across as arrogant or bossy, I just like to debate my ideas, as I’m sure everyone else here does too 😉

          • But it takes a long time to reach that equilibrium. The equilibrium you quote is itself not in doubt: if we double CO2 from current levels, and keep it there for a long time, that is the kind of world we could expect. (Not identical: there is much more north-south ocean circulation now than there was.) We can guess how long ‘a long time’ should be. Currently, we have a net heating of 2W/m2, due to the CO2 excess. Make that 4, at higher CO2. Over a year, that is an excess energy of 100 MJ per square meter. That is enough to melt 300 kg of ice. Over a square meter, that amounts to 30 cm of ice. A kilometer of ice would take 3000 years.

            Now there are many reasons why locally, melting can go very much faster. (That is the case in Iceland and may be the case in Greenland.) But at the end of the ice age, it took 10,000 years to melt 2 kilometers of ice. That is 20 cm per year. So the numbers do make sense. To get to the type of world you describe will take thousands of years. And CO2 does get removed from the atmosphere, so when fossil fuels run out, over a thousand year we go back to the old levels. But this is why, for the next hundreds of years, sea level rise of 5-10 meter is much more realistic than 20-50 meters.

  6. I live in the northeastern part of The Netherlands, in our neighbour’s backyard there is another Pinatubo-like caldera. It is the famous Laacher See Caldera in southwest Germany in the eastern part of the VulkanEifel volcanic province. Laacher See had a VEI-6 eruption 12,000 years ago, just like the Pinatubo in 1991. Pyroclastic deposits of this eruption are visible at the Wingertsbergwand. I call Laacher See Volcano “Pinatubo am Rhein”, Pinatubo upon Rhine. Laacher See is still an active volcano which still able to erupt again. CO2 is still bubbling from this caldera. A new VEI-6 eruption of Laacher See will spell disaster for Germany and the rest of Europe.

    Pyroclastic deposits:

    Laacher See Caldera:

    Multiple links in the same reply cause posts to go into the moderation queue, no big deal it’s rescued now! /admin

    • I applaud your actions. This proves that it isn’t just me with the concept of “don’t be there”

      Meanwhile… from a few years ago…

      • We have a little guy next door about 6 years old bright curly red heir freckles -the works.
        he was outside the house when some lady asked him (this was yesterday)
        “Ohh aare you a leprechaun?” he looked perplexed and said ‘No I’m a Mormon..”

        • 😀

          My reason for posting the vid was so ‘yall could get an idea of the general intellect in the deep south. (Grin)

    • Portland has a lot of older brick buildings. Those tend to fall down in even moderately large quakes e.g. 6.8 or 7.2.

  7. we are watching a movie “Magma: Volcanic Disaster” with 2 stars…. probably from both people who made it thu the whole movie… Anyone seen it? Should i just bail now and go to bed?? It’s almost midnight here. ???

    • It takes real talent to turn a volcano into a movie with only two stars! But perhaps not the right kind of talent.

    • Its not the worst one out there. (Even though recent events in iceland made it quite dated and the volcano is polite enough to hang lights in their lava tubes). But doesnt really do anything new with the disaster genre either like “Airplane vs Volcano” did. Nor does it have the charm older movies like “When time ran out” or “The devil at 4o clock have” But atleast it doesnt use shots from 911 to make believe a volcano is erupting in New York

      Once they start discussing nukes you can probably go to sleep. Unless you want a chuckle out of the world map shown later.

      • The debris cloud from the 911 collapse has been studied due to its remarkable similarity to pyroclastic flows from eruption column collapse. The greatest difference being the flow temperature.

      • i laughed at the lights hanging in the lava tubes too! And You are right; it’s not the worst one out there. Thanks for the reply, Best!motsfo

    • I usually try to find the blatant errors in how the volcano is depicted. Such as hawaiian style basalt from a rhyolite eruption. Sure, it can happen in a bimodal eruption, but not a whole lot of places give you those circumstances.

      • What’s your opinion on Frodo and Samwise surviving on a rock with their skin intact and their lungs functioning well enough for speak, let alone their eyeballs having enough moisture to see and blink? What kind of volcano belches highly fluid, non-toxic, cool lava?

        Loved the movies though.

        Rescued from the dungeon /admin

      • I tend to call those hollywoodian style eruptions.

        Activity starts with a single earthquake which can only be recognized as magmatic by disproven experts or most insane conspiracy nut. Then without any earthquakes or other signs, the rising magma forms dykes around the volcano towards natural or manmade caves filling them with lava before finally forming two main dykes.

        The biggest one goes to the top of the volcano or nearby drilling instalation where it erupts in a large fountain of lava and spits out the occasional fireballs. This activity goes on for hours until a cataclysmic explosion occurs and the volcano goes back to sleep. Ash is rarely created in this type of eruption.

        However, if the second dyke is opened up, like with a nuclear explosion. The volcano loses pressure and shuts down instantly.

        Claims by witnesses of this type of eruption that the lava deliberatly targets scientists with outlandisch theories or beautiful woman. Or has a sense of karma against sceptical scientist or corrupt businessmen have yet to be proven.

        • Don’t forget the air burst nuke for yellowstone in “2012”. Thats the one where pickle eating Woody Harrelson got hit by a small stand of trees + dirt.

  8. Great piece – one possible error near the beginning:

    ‘The cause is bradyseism, where water circulating underground causes periodic inflation and deflation’

    Shouldn’t that be ‘where magma circulating…’?

    Our spam filter has gone into overdrive today and quarantined this comment. Hereby released – admin

    • Thanks! But it is not an error. The ups and downs in large calderas are caused by underground, heated water. Of course magma can also cause inflation but in these calderas the main effect is from water.

  9. The Chinese space station, Tiangong-1, is coming home. The regular orbit-raising rocket firings became impossible two years when the control system failed. Ever since, it has slow been drifting down. In January, it was still 280 kilometer above the ground. Now it is down to 240 km and from here the decent will accelerate

    Best projection are that it will come down over the Easter weekend or the following week. Most will burn up but parts will probably reach the ground. The area at risk runs from 43N to 43S, with the largest risk between 30 and 43 degrees latitude, either north or south. This includes part of the US and China and other places include a lot of ocean.

    • From what I understand, the Chicago to Detroit segment has a high probability of catching it. Some have recommended hitting it with projectiles to break it up. Given Chicago and Detroits reputations, there’s a good chance it will receive gun-fire on the way down. 😀

        • You could say the same thing about Texas or northern Michigan for that matter. I have family in both.

        • 37% higher chance of being gunned down over the rest of the US?

          • …well, maybe Austin…where police open fire on vehicles that just exploded.

    • I actually live literally right on the southern extent of the green area, where it has a very high chance of entering… Noice. Might see it happen.

    • “Best appreciated in the original Klingon”

      One of the funnier lines in the movie.

  10. ok so with tiangong falling – how hard is the impact calculated to be (if it stays more or less in one piece) – and (for fun) is it hitting camp phlegri the biggest (and/or most likely – as its a fairly large area) disaster movie plot coupon ? are there better target volcanoes in the ‘likely to be hit’ areas ?

    • This thing is gonna be scattered over many kilometers. The worrisome bit are the larger denser chunks. Empty spun fiber (graphite/fiberglass) tanks of about 40 lbs can get to the surface without leaving an obvious crater. That happened in Spain a few years ago from (asumedly) one of our platforms. How wide the debris field is depends on how it’s put together and how high it is when that part falls off. Aero drag will become greater as time goes on and speed the deceleration.

  11. New inflation on the pu’u o’o tiltmeters. Nothing new really with this being hawaii, but there might be a new lava flow soon. The last two lava flows there started this way in 2014 and 2016 so a new one in 2018 would fit the trend pretty well. Might be the end of Johns epic lava buisness for a while though if the lava breaks out to the north again though.

    • A very notable burst of inflation:

      This may well end in a new event on Pu’o’o . But not yet: compared to the previous events, this inflation has some way to go

      • Either way there will probably be a bit more lava in hawaii in the near future, even this amount of inflation would probably cause a small surge if it breaks out through the existing 61g vent, but the fact it is inflating while possessing a low elevation vent probably means that vent is sealing up or the magma supply rate is increasing, or both. If lava flows start from vents in pu’u o’o’s crater then things are probably going to get interesting. If the summit starts inflating or erupting as well, then we might be looking at a bit more than just a new small vent on pu’u o’o (think 2011 but more).

  12. Thanks Albert for a really on-point article! The effects of Pinatubo on the global weather have long been a particular interest of mine since it happened, but the change in GMSL was something I’d never considered.
    That the GMSL seemed to respond to a “known” atmospheric alteration that could be reasonably quantified, is a powerful observation. Climatologists (meteorologists) struggle with the specifics regarding ocean-atmospheric coupling/teleconnections (such as El Nino and La Nina episodes)…which as we know can/often evolve into closed-loop, or self reinforcing patterns on a global/hemispheric scale. The question then becomes if a particular atmospheric setup is causing ocean SST to rise/fall or is a change in SST causing an atmospheric response? (a good example is our “Ridiculously Resilient Ridge (RRR) that developed in the NE Pacific from 2011 to 2015 which in turn was responsible for a nearly 5 year mega-drought here in California). In conjunction with the RRR, was an anomalously warm “blob” of water that was also pooled up in the far NE Gulf of Alaska…and I don’t think the jury is in (even today), whether the warm water “blob” was setting up the ridge, or the ridging (and clearer than normal skies) was increasing insolar heating of the ocean water (obviously both, but which one was the “main driver” that triggered the loop is what’s poorly understood..very much a chicken and egg scenario). In the case of Pinatubo, we get perhaps the first glimpse (since the satellite era began) of coupling going in one direction—-i.e. the air cools firstly, independent of the existing SST’s, which then later responds.
    Pretty powerful stuff, IMHO…and I’m sure will be useful in future modelling of atmos/ocean coupling events….even those not directly volcanically related).
    And lastly, I do have one question perhaps you can answer?
    Last year, we were CLOSELY monitoring the critical situation regarding a possible Oroville Dam collapse.
    At this reservoir, inflow and outflow is well monitored, and what we observed was that with a steady inflow, the rate of rise (in elevation) of the lake slowed down. What we deduced was the areal surface area of the lake was increasing, so the lake level rise was becoming predictably less for a given acre/ft of inflow….ie.. think of the lake as a bowl.

    Fortunately, this was all just a fun exercise since the dam held (but the nearly $1B price tag to repair it is hard to swallow), but it raises the question of whether surface area changes of the oceans due to inundation(s) is being factored into predicted rate of rise of GMSL…..or is the effect too insignificant to worry about?

    • I would expect that the increase in surface area is included in the models (it is an easy thing to add) but it will be a very minor contribution. Two other effects come into play. One is the level of the sea floor, which goes down when glaciers melt and sea rises, because of isostatic rebound and because of the weight of the added water. The second is the gravitational force of the glaciers themselves which pulls up (a little) the water around them. I believe that both are accounted for in the models.

      • Thank you Albert for the additional information!
        That’s now 3 items of interest that I’ll need to do more research on.
        Love this place.

  13. From the article.

    “Examples of cities with increasing flood risks due to (probably) self-inflicted subsidence include Djakarta and New Orleans.”

    New Orleans is particularly strange. Pretty much the entire city is within the levee system and drained. As the water table drops, it exposes the old buried cypress swamp debris to air, which then rots and looses volume, lowering the soil elevation. The outlying islands are loosing mass due to normal erosion and are not being replenished with silt from the river because it has been confined to a navigable channel. Lower and smaller outlying islands mean hurricane surge is less impeded.

    Katrina was not a one-off. In 1965, Hurricane Betsy also breached the levee system and flooded New Orleans.

    Trivia ‘yall may not know. The Army Corp of Engineers had been in litigation over the 17th st levee from a construction company trying to recoup losses it had while trying to make the sheet wall stay in compliance. (It kept shifting out of alignment) Their argument was that the geology of the subsoil was not as stated in Corp of Engineers geological reports. The Corps of Engineers judge ruled in favor of themselves.

    • The canal next to that levee is the outflow conduit into lake Ponchetrain from one of the pumping stations.

  14. OT help please, DH says that the missing Indonesian plane(the one they never found any trace) has been found…… i hadn’t heard it…. searched but could only find other plane wrecks; several were lost in the area. Does anyone here know for sure? Sorry to be so OT but You (collective) are one of the few spots on the internet that i trust for accuracy. Thanks, Best!motsfo

      • are You sure?? sounds like a gunshot?? and a vol. is usually a more constant roar. but i’ll be the first to admit i don’t know everything.. 😉 Best!motsfo

        • I could be wrong. I don’t know everything either. 🙂 I’ve heard volcanoes do many different sounds. I went back and listened again with my earbuds on a couple of times. I think it is Shinmoedake. It’s the first part of the eruption with some rumbling after that.

          • That’s the shockwave from the explosion. The delay is around 30s which puts the camera at roughly a 10km distance from the volcano.

          • Thanks.😀 I knew somebody on here would explain and was wondering how far away it was from the cam.

          • Another very good example is this video. Watch the clouds and you can actually see the shock wave. “Holy smoking toledos” pretty much says it all 🙂

          • That’s a great video of Shimoedake cdaley55, good find.
            The PNG video is a favourite, i especially like the Wilson clouds and the onlooker’s choice of language – think i’d have said something a little harsher. I’d also imagine that those below deck on that freighter close in would have had ringing in their ears for days after.

          • Tomas, I had seen this before & forgotten about it. It’s a great video for showing shockwaves. I’d feel safer watching it from a distance on land than on a boat though. 🙂

            Swebby, It sounds like the guy caught himself before saying Toledo or had a loss for words. 😀 😀 Can you imagine feeling that in your chest when it got to you? Amazing!

    • Thanks for the video. Recently I found this page on the japanese meteorological website that has quite a bit of current reports on their active volcanoes. It’s updated daily and google translate works fairly well (except of course the fully japanese pdf files)


      When Shinmoe-dake started erupting, I also started checking the webcam of Ebino (Iozan), a tiny volcano also part of Kirishima and I noticed that the fumarole got quite big about a few days ago (over 100 m easily, usually it’s hardly visible). The reports confirmed it as well.

      I wonder if the unrest at nearby Shinmoedake is effecting this one as well now.

    • Says it happened near a place called Suswa, which I’m presuming is near the volcano of the same name. This looks like a pretty significant rifting event so maybe there could be some volcanic activity too. I dont know if there is much monitoring in the area so things might happen by surprise.

      • Looking at the video, there looks to have been serious surface flooding on the plains/fields. Maybe the fissure was there for a while having grown slowly and has now collapsed at the surface due to erosion from flood water? If not, that is a large surface movement, comparable to some of the photos of the graben that formed at Hohlraum.

  15. HVO was kind enough to respond to my curiosity:

    Is there any discussions available to the public about the activity around Pahala? Is it a “new” magma chamber at 20mi depth? Are there or will there be any gps instruments installed nearby? thanks


    VHZ HVO ASKHVO, GS-G-WR (sent by jbabb@usgs.gov)
    1:28 PM (1 hour ago)
    to me
    The number of deep earthquakes in the Pāhala area has indeed been high. In fact, the seismicity rate in that area has been building over at least the past 10 years, with some suggestion that it is at its highest level in several decades. Most of the earthquakes are deep—in the 20-40 km range—and have small magnitudes. Thus, they have not posed a seismic or volcanic risk.

    The Pāhala earthquakes are part of a family of earthquakes that we believe mark the subsurface conduit from the mantle hotspot (greater than 40 km depth) to the magma storage area beneath the summit of Kīlauea (about 3-5 km depth). The magma appears to rise nearly vertically below the seafloor just offshore of Pahala, and then travels more-or-less horizontally at a depth of 20-40 km from there to Kīlauea’s summit magma reservoir.

    We have seen swarms of similar earthquakes (20-40 km deep) at this location six or so times in the last 30 years, but none of these earthquake swarms have correlated with Kīlauea summit activity.

    We are closely monitoring the Pāhala earthquakes, tracking their depths and magnitudes, as well as watching for any signs of deformation through our existing monitoring network.

    Hope this info helps.

    • Wow. A governmental agency that gives a useful response. Impressive.

    • So the deep magma source for kilauea is actually under that area? I wonder if that is significant seeing as that area is basically straight line between loihi and mauna loa. Also if the last time there was earthquakes was before the lava lake in halemaumau formed, them that is one difference between the earthquakes recently and those from before. And seeing as the lava lake has been consistently very high basically all the time since 2015, maybe it is related. Maybe the impending new breakout on or near pu’u o’o (based on recent sudden inflation, see above) might be a bit bigger than anticipated if the lava from the summit drains out to pu’u o’o simultaneous with a new breakout. Not much significant volcanic activity has happened in hawaii since 2011 so i think something is about due to happen 🙂

    • That is very interesting. Kilauea was claimed to be on a secondary line of volcanoes, connecting to Mauna Kea, with Mauna Loa and Lo’ih’i on the first line. Putting the magma conduit of Kilauea on the Mauna Loa track changes that. The magmas are not identical though, so presumably there are separate, long-lived magma stores below each of them.

      The Pahala swarm is located underneath the steepest part of Mauna Loa. The magma may be coming up through cracks / faults caused by the stress from the weight of Mauna Loa.

      • If the swarm is at over 20 km deep though would fractures on mauna loa actually extend that far down? Maybe its sort of a coincidence that the magma comes primarily from a place that is today exactly under the southern coast on mauna loa, because kilauea isnt entirely younger than mauna loa, a lot of mauna loas existing volume probably predates the formation of kilauea.

        In this paper it does mention something interesting though. Some of the earthquake patterns and magma composition of the 1959-1960 eruptions are different to the main magma supply, apparently originating deeper and further to the north of the caldera, which is a pretty huge distance from the earthquakes at pahala, so unless that information is outdated, it seems like the potential catchment area for the hawaiian volcanoes is huge but usually localised. Maybe kilauea and mauna loa actually do partly share a common source around that depth where their catchment areas overlap, and maybe that is why pu’u o’o is so long lived while mauna loa has been entirely dormant since pu’u o’o was newly formed – some of the magma was going to kilauea when it usually would go to mauna loa. I guess the same situation would apply to loihi only on a smaller scale.

  16. Wednesday
    21.03.2018 22:56:02 64.621 -17.414 8.0 km 4.3 99.0 5.9 km ESE of Bárðarbunga

    • Some more quakes followed in the same area (southeast of Bardabunga). Wonder if this is at the southern plug rim and if they are the large quakes that Thomas A postulated to come and balance the northern rim quakes? Or are these ones to far east?

      • Yes, this is on the southern rim. It is a bit smaller than I expected and it took a couple of weeks too long to arrive for me to feel happy. Since it’s a bit smaller than expected, I think there is a decent chance that we will see another one of similar size in the same area in the next few days.

        • There were two precursor quakes, one SE but not in the same area, and one in the NE but within the caldera. Both a bit shallower than the main quake. They all look tectonic. The earlier quakes perhaps show how the stress is transfered between the SE and NE parts of the caldera. The fact that the precursors were more shallow would be consistent with inflation but that is a bit speculative.

        • After looking at the data again I realize I probably extrapolated a bit too much. Here is a cumulative seismic moment plot of the southern caldera rim. I have added a line that upper bounds the staircase plot. It is striking how well the corners of the staircase matches the straight line. I’d like to think that the difference between the straight line and the cumulative seismic moment curve is a measure of the currently built up strain and thus a hint on the potential size of the next quake. For the south side the last quake actually brought the staircase all the way up to the straight line, so contrary to what I said earlier today it probably released most of the built up strain for now.

          Looking at the north side instead, the data does not fit quite as well. Since July 2017, the slope has changed significantly. If the line I have drawn here correctly represents the current average rate, then the current separation between the staircase plot and the straight line suggests that there is enough built up strain for a single M4.8.

          I’m aware that the way that the staircase touches the line in a few points may well be a coincidence. Maybe tomorrow we get a big M5+ that throws everything off the scale again, who knows. We can try to find patterns, but in the end volcanoes still do whatever they feel like.

          • Not in a while and when I did I only did it for the entire caldera. Last time I checked I binned the energy release over depth into 1km segments. At that time, the distribution was uniform down to about 10km. If I get time I can do the same exercise again tomorrow and include separate graphs for the south and north caldera rims respectively.

    • Sadly not. No sign of a SSW on the weather models and the cold air is being pulled down by a mid latitude low pressure this time. It’s Artic air rather than Siberian.

      I doubt there’s any correlation between the eruptions of this year on stratospheric conditions. There’s been nothing big enough.

      Don’t believe anything in the express, it’s pure scaremongering nonsense.

    • correct me if i’m wrong, People, but i think the unusual cold is from global ”
      “warning” (as ‘warming’ is considered NonPC) as the jet is wobbly and not containing the polar low… anyway not due to volcanoes… Best!motsfo and there is an upside… Your dyed eggs will be easier to find in the snow… Best! from motsfo still in the snow but this is alaska so …

      • Dunno. A few years ago, I had a grandkid find an egg from the previous year. When it exploded in a puff of yellow powder on him, he shrieked. At first I thought he had found a snake that the dogs missed. (I let the dogs run the yard prior to any egg activity to lessen the hazard)

        • april first (april fools day) for easter sunday – so egg hunt begins at dawn with no eggs to find until after lunch seems to be in order.

    • Hi Janet, not read the article (tend to avoid the our tabloids) but the SSW happened in Feb, it was a biggy and the effects of a SSW tend to take their time to work their way down to weather at the surface. At the time it happened in Feb, i read that a classical response in weather at the surface to a SSW would probably happen in three waves, one at the end of Feb, one in the middle of March and the biggest at the very end of March. If we get a white Easter here in the UK, that would turn out to be an impressive prediction!
      The causes of a SSW seem difficult to pin down with a number of suspects being proposed. Ozone movement in the stratosphere is meant to one possibility so large eruptions could well have a bearing on this but as beardy gaz points out we’ve not had anything of that order for a while.

  17. Inflation at pu’u’o’o is accelerating. The amount it not (yet) large but it is impressive. And the inflation is beginning to show a bit at KIlauea as well.

    • I think the tiltmeter or gps is on the rim of the crater, and before the 61g flow started there wasnt much inflation at the gps but the thermal camera showed the floor of the crater visibly getting higher for about a week before the breakout, so there actually might be a pretty significant inflation happening inside the crater that isnt obvious at the edge. When the breakout eventually happens HVO will probably release a short video showing the said inflation.

      • The summit lava lake has risen to 20m below crater rim, it has been hovering around 30-40m for the last several months, definitely some pressurisation going on.

        • Its been above 40 meters about 90% of the time since April 2015 when it overflowed. At the same time since 2011 pu’u o’o has bee a bit less productive (which is why the lava flows since then have usually only reached the ocean once and then never have enough flow rate to get that far again) Maybe someone could make a plot of this to roughly extrapolate when pu’u o’o will stop erupting.

          I think the constant lava flows will continue long after pu’u o’o stops though as the summit vent will probably overflow frequently in the years immediately after pu’u o’o goes extinct. I wouldn’t be surprised if it fills halemaumau before this century ends, providing that the magma supply rate stays relatively constant. It did the same sort of thing in the middle ages up until 1480 or something before its caldera formed and started to fill in 1790. It filled very fast after that.

  18. Press Release: Ijen Volcanic Activity, East Java Related Toxic Gas Events In Watucapil Village, Sempol

    Partly Translated.

    ”According to Sempol residents, on 21 March 2018, at 21.00 WIB, in the village of Watucapil there has been a sulfur gas poisoning that happened to 27 people and the victims were treated in Pukesmas Ijen, Bondowoso.

    Coordination with BKSDA Region III Jember as the manager of Ijen Crater, sulfur miners, Head of Ijen Puskesmas, Polsek Ijen and Dandim Bondowoso. Agreement with the head of Resort BKSDA Ijen to temporarily close the ascent to the top / crater of Ijen from start Paltuding.”

    Full article:


    • I don’t have a good location for the village, but Gurgle Eart places it at Air Terjun Gentongan, a tourist attraction. This is 7+ km from the sulfur mining operation at the crater…. but slap dab in the middle of the main Kendeng caldera. Ijen and the crater lake are later structures along the ring fault system of it.

    • And a pretty decent paper describing the main caldera. Complete with a cross section of the system at ground level.

      From the paper (edited for readability);

      “…The caldera formation is associated with the eruption of a large volume (~80 km³) of pyroclastic flow deposits, which reach a thickness of 100-150 m and are most widespread on the northern slope of the complex. The event occurred some time before 50,000 years ago, based on a K-Ar date (50 ± 20ka) of a lava flow of Mt. Blau, which is considered to be the oldest post-caldera unit… “


    • Still from that same paper; “A survey in 1997 also revealed that concentrations do not vary markedly with depth”

      This likely means that the lake is fairly well mixed and doesn’t show stratification. So, lake overturn is an unlikely source. (plus it’s probably 7+km away)

      My interpretation is that it is probably sourced from local seepage near the village. The caldera system is well known for high sulfur concentrations, and it is a highly fractured caldera floor with multiple resurgent features and cones. At about 50kyr age, it really hasn’t had time for the caldera floor to re-seal into solid rock. Large Caldera eruptive event unlikely… but a new vent is not out of the question in the geologic future. (in other words, yeah it could happen, but within a very long time on the human time-scale)

      For anyone who is not familiar with my terminology. “Large Caldera Event” is my preferred term rather than the media constructed and much hyped “Supervocano,” which has no real definition. Granted, my term also has no definition, but it lends itself to a defined set of conditions, that being in the upper 25% to 50% of all caldera forming events. That also allows it to encompass more catastrophic eruptions than just the assumed VEI-8s that has been cobbled onto the medias Stupervolcano term.

      Is it important? Not really. The VEI scale already has enough problems as it is, and my pet term doesn’t really merit much attention. I just don’t like being played by the media and will stick to my term since it’s more useful in my eyes. Carl and Albert made a stab at sort of fixing the VEI scale and came up with one that takes into account Flood Basalts, but I don’t know the details.

      The problem with VEI → It is based off of how much stuff came out of the hole and doesn’t really address how fast it came out of the hole. A long duration mediocre eruption can easily score a higher VEI number than a short period high energy eruption. If I remember, one of the recent Indonesian volcanoes let loose a very high energy eruption that lasted for all of 15 to 20 minutes. The column was nearly high enough to inject SO2 into the stratosphere. Had it lasted for 6 hours (not uncommon for volcanoes) it would have easily been VEI-4 or higher.

      Now, when you try to factor in Flood Basalts, the whole system goes to hell in a hand-basket. Lakagígar, Eldgjá, or Veiðivötn all put out a copious amount of lava, but may or may not have been able to produce a high altitude plume. (The magma spray from Laki (fire curtain) has been reported to heights higher than the tallest modern buildings) Much of the energetic activity was from groundwater interaction. (Rootless cones)

      Trivia note. Though the 1783 Laki event carries that name quite a bit, the volcano Laki never actually erupted. The fissure line ran up to the base of Laki, then reappeared on the other side of it and kept going. That it didn’t suffer the fate of Mt. Tarawera is sort of amazing. Tarawera was cleaved in two by a fissure. (10 June 1886)

      • More Translation.

        ”On March 21-22, 2018, the visuals are sunny to cloudy, the winds are weak to the southeast and south. Air temperature 18 – 28 ° C. The volcano was clearly visible until it was covered in fog. Crater smoke is white with moderate to high intensity about 100 – 200 meters from the peak. Earthquake recorded 2 times the volcanic earthquake (VA). 19 times shallow Volcanic earthquake (VB). 1 time Blowout earthquake (HB). 3 times the tectonic distant earthquake (TJ). 1 times Tremor (TR) earthquake. Anomaly changes in the number of shallow Volcanic Earthquakes (VB) dated February 24 – March 2, 2018, March 10-11, 2018 and March 18-21, 2018.

        Gas concentrations detected three gas anomaly concentrations during the period of January – March 2018, ie: January 10, 2018, at 12:56 WIB where CO2 gas is about 2563 ppmv, SO2 3,6 ppmv, and H2S 2,4 ppmv; February 19, 2018 at 13:26 pm, detected CO2 gas reached 5139 ppmv, SO2 146 ppmv, and H2S 23 ppmv; and on 21 March 2018 at 19:24 WIB, CO2 gas reaches 5140 ppmv, SO2 is not measurable (may exceed sensor capacity), and H2S 175.8 ppmv. This anomaly is interpreted as a sudden gas blowing or outburst gas in the crater lake caused by “over pressure” mainly by the continuous accumulation of CO2 and H2S gas in the crater lake.

        Potential hazard

        Potential danger of G. Ijen eruption in the form of threat of toxic gas flow, hot cloud flow, hot mud, lava flows, heavy ash rains and eruptive lava within a 1.5 km radius of the eruption center. The flow of hot clouds, lava eruptions, rain lava, heavy ash rains, the possibility of avalanches of volcanic debris and bursts of incandescent rock within a radius of 6 km from the eruption center. Under lava flows, possibly expanding hot clouds or eruptive lava, heavy ash rains, may be exposed to incandescent rocks within a radius of 8 km from the eruption center.

        Recent activity

        After the occurrence of gas blast on March 21, 2018, visually not visible changes in smoke, smoke color, smoke pressure, and water color crater. Shallow Volcanic Earthquake (VB) until March 22, 2018, at 16:00 pm seismograph recording 14 times Volcanic earthquake and 1 times a blowout earthquake. This condition shows that the seismicity of G. Ijen is still recorded above the daily average. Based on the result of visual monitoring, seismicity and gas concentration, activity level of G. Ijen is still Level I (Normal).

        In connection with the occurrence of such events, then:

        People and visitors / tourists / climbers / miners are not allowed to approach the crater lips or near the base of the crater at the summit of Ijen Crater Volcano and can not stay in the area of ​​Volcano Ijen Crater.
        Communities / visitors / tourists do not need to panic with the emergence of the phenomenon of the emergence of toxic gases, and do not trust the issues related to the situation in G. Ijen is not clear source.
        Community / visitors / tourists to keep following the direction of the tour manager G. Ijen (BKSDA).
        Tour manager G. Ijen (BKSDA) should make a warning boards “Watch Out Danger of Poisonous Gas” starting from Paltuding to G. Ijen crater.
        If the smell of sulfur / sulfur gases that sting / concentrated, then the community / visitors / tourists to use a mask cover the breathing apparatus. For short term / emergency can use wet cloth as cover of respirator (nose / mouth).
        Tour manager G. Ijen (BKSDA) is expected to always coordinate with Observation Post G. Ijen in Licin, and Center for Volcanology and Geological Hazard Mitigation, Geology Agency, Bandung directly or via telephone (022) 7272606.”


        • H2S

          0.00047 ppm or 0.47 ppb is the odor threshold, the point at which 50% of a human panel can detect the presence of an odor without being able to identify it.[34]
          10 ppm is the OSHA permissible exposure limit (PEL) (8 hour time-weighted average).[19]
          10–20 ppm is the borderline concentration for eye irritation.
          20 ppm is the acceptable ceiling concentration established by OSHA.[19]
          50 ppm is the acceptable maximum peak above the ceiling concentration for an 8-hour shift, with a maximum duration of 10 minutes.[19]
          50–100 ppm leads to eye damage.
          At 100–150 ppm the olfactory nerve is paralyzed after a few inhalations, and the sense of smell disappears, often together with awareness of danger.[35][36]
          320–530 ppm leads to pulmonary edema with the possibility of death.[26]
          530–1000 ppm causes strong stimulation of the central nervous system and rapid breathing, leading to loss of breathing.
          800 ppm is the lethal concentration for 50% of humans for 5 minutes’ exposure (LC50).
          Concentrations over 1000 ppm cause immediate collapse with loss of breathing, even after inhalation of a single breath.

          SO2 see https://www.atsdr.cdc.gov/toxprofiles/tp116.pdf

  19. Maly Semyachik in Kamchatka raised to Yellow alert. Last eruption 1952.

    • Well, Janet, i’ve been watching that area since our last big’er’ one located just in the northern Pacific plate… i’ve got my ideas (not an expert) thinking about maybe another plate breaking off like the Juan de Fuca plate?? But You are right; somethings up. Maybe the Pacific plate isn’t so excited to just slip under the north American plate any more. Best!from motsfo on the Kenai Peninsula just north of all this rock and rolling… 😉

      • You sure live in one of the most breathtaking part of the world (just been looking at photos and videos on Lonely Planet ):)

    • You got there before me! Yes, interesting article from the Beeb. Rainfall, seismic activity, magma bulges… I think there are plenty of threats that could exacerbate the movement and flank collapses in volcanoes has a bit of a history. Glad folks are watching it. However, I suspect we could be looking at decade, if not hundreds of years before anything significant occurs.

      I wonder what the annual movement is in La Palma?

      • Mt etna has been really quiet for the past few years, it has only erupted 3 times since 2015, which is pretty low rate there… Maybe it is forming a magma chamber under its central summit vents and there will be some more significant activity in the coming decades, something like the period from 1600 to 1669 when there were multiple very large lava flows and long lived flank eruptions at low elevations.

    • “The Yellowstone hotspot, located in North America, is an intraplate source of magmatism the cause of which is hotly debated,”

      Pun intended? 🙂

    • That is the Öræfajökull volcano slowly approaching its next eruption. Most likely it will take about a decade to prepare for the action, much like Eyjafjallajökull did before its 2010 eruption, but as always volcanoes don’t do schedules so things may happen sooner or they may take longer.

  20. Don’t forget that the sea also is rising due to the Land rise where the ice age ice cap used to be (huge areas in Canada and Scandinavia). Another big source of sea rise is all the water that used to go into lakes bu now ends up in the sea due to agriculture. Dead sea and other lakes without outlet are lowered drastically. Almost half of the sea rise can be bound to that source. This has however decreased during the last fourty years as New power dams has been built at astonishing speeds, compensating for the loss of water in natural lakes.

    In reality roughly half of the current sea rise comes from global warming.

    • The isostatic rise of the land around the old icecaps is included in the models and is not part of the global rise. It only affects a few, relatively small areas around Scandinavia, Scotland, and Canada (you forget how big the Earth is, and that the ice caps only covered a small area.) The lake levels and agriculture you mention have no significant effect, and the hydro dams are also insignificant on a global scale. There is some impact from the fact that the atmosphere now holds more water, because it is warmer (of the 55 inches of rain in Houston from the hurricane, 5 inches can be attributed to this.) Half the current sea level rise comes from melting of land ice. The other half comes from warming of the oceans, causing the water to expand. There is no third half.

      • Not to be forgotten about isostatic recovery is the ‘downside’. In the UK, as the north and Scotland rise up from the release of pressure, so the south of the UK sinks. I’m collecting sandbags here in central Surrey. Just in case the sea floods the Mole Valley!

Comments are closed.