A New Horizons image of Pluto showing its big heart
Its career as a planet last for less than half its year. Pluto was discovered late, in 1930, as our final planet, completing the Sun’s brood of nine. (In hindsight it had been seen, but not recognized, as early as 1909.) But it was always an odd one, the runt of the litter, banished to the far flung regions of the Solar System. By 2006 the International Astronomical Union had seen enough. It instigated a new class of objects, intermediate between planets and asteroids (or minor planets), and re-assigned Pluto to be the primary member of this class, called dwarf planets. There were good reasons to do so: Pluto was just too small, on too strange an orbit, and worst of all, similar objects were being discovered. If Pluto was a planet, perhaps as many as 50 other objects out there could claim planethood too. NASA astronomers objected vehemently. NASA had just launched a mission to Pluto, called New Horizons. US Congress would not be well pleased if its money, awarded to investigate the last unexplored planet of the Solar System, would end up at a dwarf planet instead. The objections were overruled by a convincing vote. 76 years after being discovered and named, having travelled only a third of its 248-years orbit around the Sun, Pluto’s brief summer as a planet came to an end.
Still, this newly-named dwarf planet, frozen beyond belief, is a fascinating object. It has everything: weather, enormous climate change, active geology and volcanoes, a large heart on its surface, a family of satellites, and a mysterious past. Maybe being a dwarf planet should be a badge of honour, worthy of every penny spent by NASA.
An interesting aside, the name Pluto was first suggested by Venetia Burney, 11 years old at the time and living in Oxford. Of course we don’t know who named the original planets but perhaps this was also the work of children. Children have curiosity and want to push their horizons. Space was made for them.
This post will present our knowledge of Pluto, and its place in the Solar System, prior to the New Horizons encounter. Other (later) posts will be about New Horizons itself, and what we learned from the fly-by.
Children of the Sun
(solarviews.com)
Two decades ago, when everything was simpler, the Solar System had only two types of planets: the rocky or terrestrial planets (Mercury, Venus, Earth and Mars) and the gas giants (Jupiter, Saturn, Uranus, Neptune). Pluto as a solid body was classed with the rocky planets.
The four rocky planets all have iron cores, underneath a silicate mantle. They have only small amounts of the so-called volatiles: water, methane, CO2. There is a reason for this deficit. The planets formed from solid particles which came together. Each mineral has a temperature below which it can be a solid (there is no liquid phase in vacuum). For iron and silicates, this condensation happens at when temperatures drop below a balmy 800-1000 Kelvin, but water, methane and CO2 freeze out only below a chilly 200 K. The rocky planets formed at a distance from the young Sun where the temperatures were in the range 300 to 600 Kelvin. So water, and other volatiles, were in a gas phase and absent from the solid particles which made up these planets.
The 200-K temperature was reached somewhere within the asteroid belt. This is called the snow line. Further out, water became solid. Any ‘rocky’ planets forming out here would contain major amounts of water. In reality, the boundary wasn’t as sharp as the name ‘snow line’ implies, and the fraction of water in planets slowly increases further out, being very low for Earth, larger for Mars, and larger still for many asteroids.
The four gas giants are nowadays divided into two groups. Jupiter and Saturn, the monsters of the Solar System, are true gas giants. Uranus and Neptune, rather smaller but still 15 times heavier than the Earth, are considered water giants. They contain huge oceans in their mantles, above a rocky, Earth-like core.
The moons of the large gas giants, being outside the snow line, also are a mixture of rock and ice, with more ice than found in a typical asteroid. In all these objects, ‘ice’ is mainly water ice but it also contains ammonia, CO2, and methane.
Plutonian
How does Pluto compared to the rest of the family? If you like your information in numerical form, a Pluto factsheet is maintained by NASA. But the facts need interpreting.
Pluto’s mass may seem impressive, but it is positively minute compared to the planets: it is a midget, only 0.2% of the Earth, and 20 times less than the smallest planet, Mercury. Embarrassingly, seven moons in the Solar System are larger than Pluto. The orbit is also strange for a planet, very elliptical, with the distance to the Sun varying by 50%. For comparison, for Earth it varies only by 3.5%, and for Mars (the most elliptical orbit among the planets) the variation is 18%. Pluto is in a different league. The orbit is also well outside the plane of the ecliptic where all other planets are found. It really is an outcast.
Pluto is just about large enough that during formation, the interior would have melted from the heat of the colliding fragments. The melting will have allowed the denser silicates to sink down, and Pluto is thus expected to have a rocky core, surrounded by a water mantle. There is also an atmosphere, mainly consisting of nitrogen, with a pressure of 10 microbar, comparable to the Earth’s atmosphere 100 kilometer above the surface. Temperatures at Pluto are around 40 Kelvin, or -243 C. (If you live in one of the seven countries following the Polish-born Daniel Fahrenheit, this is -387 F.)
The internal structure of Pluto. Source: wikipedia
Pluto’s giant moon is called Charon. ‘Giant’ is relative, but Charon is large enough that some consider it a dwarf planet in its own right. Whereas Pluto has a diameter of 2370 km, Charon is 1200 km across. (For comparison, our Moon is 3475 kilometer across.) Four more moons were discovered in recent years. They are very much smaller, and a bit further from Pluto than Charon. Interestingly, the orbits are in resonance: the orbital periods scale approximately as 1:3:4:5:6, which is the only way such closely spaced moons can stay in stable orbits. The four large moons of Jupiter have the same kind of resonance.
Charon takes 6.4 days to orbit Pluto (that is the ‘1’ in the 1:3:4.. sequence above). Pluto’s own rotation period is also 6.4 days, as is Charon’s day. In other words, they are tidally locked, both always showing the same face to each other, just like our Moon does to us (but the Earth does not to the Moon).
Making Pluto
How did this complex system form? It seems unlikely that a dwarf planet so far out in the Solar System can pick up 5 satellites! There are too few free objects around there for such multi-dating. The circular orbits of the moons suggest that they formed in situ, around Pluto, and were not captured from abroad. The large size of Charon is most easily explained as caused by a major impact during the formation of Pluto, which effectively split proto-Pluto in two. This impact would have been even more devastating (relatively speaking) than the one that formed our Moon. The other moons could have formed from debris from this impact. But could such a major impact have happened in such an empty region of the Solar System? Isn’t it a bit like a world-class collision in a road-less region in the desert heart of Australia, traversed by one vehicle per month?
A clue comes from the densities of Pluto and Charon. These are around 1800 kg/m3, midway between ice and rock, meaning that both are very roughly equal parts ice and rock. This is very similar to Titan and Enceladus, moons of Saturn. The moons of Jupiter, in contrast, are denser and have more rock than ice. Remember that the further from the Sun a planet or moon formed, the higher fraction of ice it contains (Earth has essentially none). Pluto will thus have formed somewhere in the general region of Saturn, which is much closer to the Sun than it is now. During a chaotic phase in the early Solar System, a lot of smaller bodies were thrown out of this region by encounters with Saturn and Neptune. It explains the strange orbit of Pluto. The collision that formed Charon could also have happened during this period of chaos.
Surface features
Long before New Horizons was launched, we knew that Pluto has an interesting surface. Its brightness changed, such that the dwarf was considerably brighter when the side facing Charon was pointed towards us. There was a more reflective material on that side, and the most likely culprit was ice; nitrogen ice, to be precise, which is white at very low temperature, around 40 K. (When ‘warmed’ to 60 K, it becomes transparent, and at 63 K it evaporates.)
The Hubble Space Telescope had a go at mapping tiny Pluto. It found a particular bright region, neighbouring a very dark area. The dwarf planet also appeared to be changing: over a decade, the northern (darker) hemisphere was brightening, and the southern hemisphere fading. Over this time, the density of the puny atmosphere had doubled. Pluto was showing seasons!
We now know that the bright region is the same as the ‘heart’ found by New Horizons. Discoveries often have history.
Seasons of the heart
Pluto’s seasons are funny. Of course, this far from the Sun’s warmth, the seasons change between winter and ice age; you would not expect to find anything resembling summer!
On Earth the seasons are determined purely by the tilt of the polar axis. The angle between the orbit around the Sun and the Earth’s rotation is 23 degrees: this tilt causes the varying length of day, and the varying height of the Sun above the horizon. Within 23 degrees of the equator, the Sun can get to the zenith: these are the tropics. Within 23 degrees of the pole, there are times when the Sun doesn’t set or doesn’t rise, depending on the season: these are the polar regions.
Pluto’s inclination is more than double that of Earth, at 57 degrees. This makes the seasons much more extreme. (The tilt is actually 123 degrees: the planet rotates upside-down and the Sun rises in the West. But the effect is the same as a tilt of 57 degrees.) As the dwarf moves around the Sun, at a certain point in its 248-year orbit the Sun will be above the equator: this is the equinox when day and night are the same length, everywhere on Pluto. A quarter orbit along, the Sun is only 33 degrees from the north pole of Pluto: the southern quarter of the planet is now in perpetual darkness and the northern quarter in perpetual sunlight. Than the Sun moves back to the equator, and finally to close to the south pole, and the polar day and night are reversed.
On Pluto, the ‘tropics’ (this name could be seen as optimistic) and the polar regions overlap: there is a region at intermediate latitudes where during the summer the Sun gets to zenith, therefore it counts as the tropics, but this Sun never sets, and half an orbit later the same region has a perpetual polar night; so it is both tropical and polar. At the moment, the Sun is not far from the equator and all of Pluto gets some sunlight. Spring has begun in the North, and the South is heading towards its century-long winter night. Pluto’s climate was designed for Sleeping Beauty.
Pluto’s year. Source: http://www.planetary.org/multimedia/space-images/charts/plutos-seasons.html
A second problem is that the distance to the Sun changes so much during the Pluto year. Closest approach occurs during the spring equinox in the North (or autumn equinox in the South). The northern summer and southern winter happen when Pluto is far from the Sun. The South therefore has more extreme temperatures – a colder winter and warmer summer. The South has climate and the North has weather. Also, note that Pluto moves much slower when further from the Sun, so that the seasons are of very unequal length.
With Pluto just coming out of the northern winter, the expectation was that at the moment there is a nitrogen ice cap in the north, in the process of evaporating, while the southern ice cap has not yet started to reform. The atmosphere is therefore denser than usual. As Pluto moves away from the Sun, much of it will condense as frost and ice, on the southern hemisphere. The ice cap resembles an anti-swallow, migrating from winter to winter.
Is there life on Pluto?
No.
Pluto’s siblings
There are four groups of objects in the outer Solar System similar to Pluto, ranging from puny to Pluto-sized. Over a thousand objects are known, several of which are large enough to be dwarf planets. Together they are called the Kuiper belt.
The first, and largest, group contains the ‘classical objects’: they have mildly elliptical orbits, around 42 to 45 AU (1 AU is the distance Earth-Sun; Pluto is at 39 AU), and most are close to the plane of the ecliptic where the planets are found.
The Kuiper belt. Source: http://www.planetary.org/multimedia/space-images/small-bodies/orbits-of-pluto-and-pt1.html
The second group have the same orbital period as Pluto but very elliptical orbits (each one different) and a variety of inclinations to the plane of the ecliptic. These are called the plutinos. Their orbits are in a 2:3 resonance to Neptune, meaning that for every three orbits of Neptune, they do exactly 2. Many cross the orbit of Neptune (as does Pluto), but because of this resonance they never come close or collide. There probably used to be more, but any that had different orbital periods were slowly removed by Neptune. Gravity is a bastard: it can be slow and weak, but it always wins.
The third group is the ‘scattered disk’: these objects are much further out and their orbits are highly elliptical. The dwarf planet Eris, almost as big as Pluto, is a member of this group. They have clearly been thrown out here after coming too close to one of the giant planets, probably Jupiter, and coming off worst. Now they are the cricket/baseball out-fielders: hanging around, not doing much, waiting to catch the odd ball coming their way.
The largest Kuiper belt objects. Source: wikipedia
Finally, a few of the moons of the giant planets are similar to Pluto, including Phoebe (orbiting Saturn) and Triton (orbiting Neptune).
Triton is in some ways the other Pluto. It orbits Neptune in the opposite direction to Neptune’s rotation. That indicates it hasn’t always been there but was captured by Neptune at some time. Triton is a bit larger than Pluto and has a little bit higher density: a bit more rock and a bit less ice; thus, it probably formed closer to the Sun, perhaps near Jupiter. Like Pluto, Triton has a nitrogen atmosphere. Triton was photographed during the Voyager encounter, in 1989. It showed a surface that is a mixture of dirt and nitrogen ice: the lack of impact craters suggests that the ice is quite young (or re-formed regularly).
The surface of Triton, as photographed by Voyager
Most excitingly, Voyagers found geysers on the surface, ejecting gas kilometers high. These were only seen where the sun was directly above Triton, in the zenith. The geysers are probably from nitrogen: phreatic nitrogen volcanoes. Nitro-thermal activity, if you prefer.
Volcanoes
The geysers of Triton raise the question how common volcanoes are, out there in Tevya’s frozen wastelands (from Sholem Aleichem’s Fiddler).
All rocky planets have volcanoes (remember Venus). These planets produce liquid rock, which rises to the surface as lava, either effusively or explosively. But the outer Solar System has less rock, and more ice. Would you expect volcanoes? And to melt the magma, a heat source is needed. Does that even exist in these small, cold bodies?
Io, the hellish moon of Jupiter, is a clear case in favour. It is the most volcanic surface in the Solar System; the heat is supplied by huge tides (on solid rock!) from its boss, Jupiter. Nearby, the asteroid Vesta once had a magma ocean, albeit only when it was young. But both of these bodies formed close to the snow line, and still are largely rock. Further out, where ice rules, volcanoes are very different.
Here, on the ice worlds, you would expect that volcanoes erupt liquid water rather than liquid rock. Many of the moons are now believed to have water oceans deep underneath the surface, and these take up the role of a ‘water magma’. But water is not a good volcanic substance. When rock melts, it becomes less dense and the magma therefore rises up towards the surface. When ice melts, its density increases and the resulting liquid tries to sink. You know this from experience: ice floats but rocks sink. Down is the wrong direction for volcanic eruptions.
Turning water into a gas does give the required upward pressure, perhaps even too much of it. This gasification can happen close to the surface and results in a Yellowstone: huge geysers erupting into the sky. (Under near-vacuum, liquid water does not exist and all eruptions become gaseous when reaching the surface.) The result is seen on Enceladus: geysers erupting from a sub-surface ocean, going so high that some water escapes altogether and ends up on other moons. The geysers of Enceladus are one of Brian’s wonders of the Solar System. Would you call this a volcano? When it goes this high, you might as well. (But to play the devil’s advocate, comets work the same way and would you call the jets that form their tails volcanic?)
Even further out in the Solar System, the surfaces are mainly nitrogen ice. When this is transparent, sunlight can penetrate and heat the material underneath. This is probably what powers the geysers of Triton. At 40K, nitrogen ice is white rather than transparent and this underground heating does not work. So one might expect that Pluto would not have such geysers.
The ninth planet
Let’s come back to the plutinos. A paper published in early 2016 pointed out that their orbits were remarkably similar, with the closest approach to the Sun occurring in the same area of space. This was a strange alignment which could not have happened by accident.
Models show that only the gravitational pull of another body could do this. This body would be perhaps 200 to 1000 times further from the Sun than we are, on an elliptical orbit with a period as long as 10,000 year, and could be as massive as Uranus or Neptune, large enough that there should be no doubt about its classification as a planet. The models appear quite convincing. We haven’t found it yet and it will be very faint. But it does appear that the Solar System again has nine planets, not eight, and the final member which occupies the vacancy left by demoted Pluto is our third water giant. It cannot have formed as far out as it appears to be now: most likely it formed close to Saturn, and was ejected during an ill-advised close approach, in the years of chaos in the young Solar System. Now it lives in the Solar System’s Siberia, far from civilization but still out there after all these years. A true wanderer.
If we only knew where it was, New Horizons could perhaps be redirected at it. It might take a century to get there, but the US Congress’ money would still be used for its original purpose: visiting the final planet of the Solar System.
New Horizons
So we knew a fair amount about Pluto. And finally a spacecraft came to have a look. New Horizons was launched in 2006, still in the years of Pluto’s planethood, and traveled for nine years, with a quick fly-by of Jupiter on the way to pick some extra speed. On 4 July 2015 it reached Pluto. Unable to carry enough fuel to stop, it flew past within hours. These hours transformed our knowledge. The dwarf planet became the world with the big heart.
To be continued
Albert
Katla Reawakening?
View over Katla photographed by Dagur Bragason today. Used by kind permission by the photographer.
Over the years I have written very little about Katla. The reason for this is that Katla has done very little to merit an article. Here at Volcanocafé we have written a few posts about Katla, but all have been attempts to put facts up against all the alarmist trash that has been written over the years.
This has though changed lately, but before we start talking about resent activity we need to look a bit at Katla to have our facts straight. In other words, we need a historic background to judge what is happening against previous eruptions. Below I will only write about eruptions that are known to really have happened and I am not included mini-eruptions or eruptions only to be found in the heads of people with feverish minds.
Background of Katla
Historic size and distribution diagram by Icelandic Met Office. Note that M3.4 was the largest recorded earthquake up to last week.
Katla is the third largest volcano in Iceland with Bárdarbunga and Grímsvötn being slightly larger. All 3 of them come with slightly different “flavours”. Bárdarbunga is more into large effusive eruptions and small explosive eruptions. Grimsvötn is all over the map producing explosive eruptions ranging from VEI-2 to VEI-6 and has had 3 known large effusive rifting fissure eruptions.
And a plot showing todays hubbub. Notice that the twin M4.5 expended 1.5 times as much energy than all recorded Katla earthquakes in one go. Image by Icelandic Met Office.
Katla is more consistent with predominantly large explosive eruptions from the caldera and one prolonged large effusive eruption. Katla has had 30 eruptions since 820 giving an average of 40 years between eruptions. That average is though just a statistical number that obviously can differ a lot.
The longest repose time during that time was 100 years and the shortest well dated repose time is 12 years.
In regards of how explosive the eruptions has been we get a pretty good picture from the records. I am here only using those eruptions that has a classification in the Global Volcanism Program from 820 and onwards. 3 eruptions had a Volcanic Explosivity Index (VEI) of 3, 14 eruptions had a VEI of 4 and 4 eruptions had a VEI of 5.
The average size of the eruptions is why Katla has such a fearsome reputation, especially since it is located unusually close to settlements. After all, the volcano has an average size of eruptions that ranges somewhere between a medium sized VEI-4 to a borderline VEI-5.
During eruptions between 0.05 to 5 cubic kilometers of ash is released and here the bad news is that the ash is very fine grained and needle like, so the effects on air traffic during an eruption could be significant depending on the weather pattern during onset of eruption.
The greatest threat to the locals is the well known very large jökulhlaups that will come pouring out of the caldera during an eruption. These jökulhlaups are so large that they can remove entire farms, take out a long stretch of the national highway and usually changes the entire landscape. During the last eruption the jökulhlaup transformed the entire coastline below Myrdalsjökull and the ash, mud and stones deposited added several square kilometers to the surface of Iceland.
The extreme oddball of the eruptions is the Éldgja fissure eruption that started in 934 and lasted into 940 and deposited 18 cubic kilometers of fresh lava.
Current activity
Alftagrof station, image by Icelandic Met Office.
In 2013 the earthquake pattern of Katla changed and recurrent brief episodes of small deep earthquakes started. Those earthquakes range between 20 and 30km+ depth and are a sign of magma moving upwards into the system of the volcano. During early 2016 the size and frequency of these earthquakes increased indicating an increased rate of magma influx from depth.
During all of the years that we have had instrumented recordings of earthquake sizes in Iceland Katla has suffered a few M3+ earthquakes with the record being at M3.4. So it was a bit of a surprise last week when Katla banged off an earthquake that was M3.5. It was shallow and the signature indicated that it was related to hydrothermal activity caused by fluid movement.
And here we come to today’s earthquakes. During the night leading to today there was a brief and intriguing earthquake swarm in the northern part of the caldera. A spot that Henrik Lovén already in 2011 pointed towards being both the most likely spot for an eruption, and as being the most likely for a slightly larger eruption in a series of articles he published here debunking that Katla would erupt soon (it was during the Katla scare following Eyjafjallajökull).
So, what makes this brief earthquake swarm so interesting? First of all we have to take into account the size. After all we had a new record earthquake size last week, and now we had 2 earthquakes within 20 seconds apart measuring M4.5. And as everyone knows the destructive force is 27 times larger in an M4.5 earthquake compared to an M3.5 earthquake. So, the record was not only broken, it was shattered completely.
Another way to look at it would be like this, within a minute Katla released more seismic energy than has been recorded by instrument for that volcano. Yes, those two earthquakes released more energy than all of the ten thousand plus recorded earthquakes at Katla, something to ponder indeed.
Another thing is that during the hour prior to the two large earthquakes we have several episodes that can be interpreted as fluid movement and one episode after. This would indicate that fluid started to move, putting pressure on the magma reservoir causing two large tectonic type earthquakes that in turn created a void that more fluid moved into.
The depth of the events makes it highly unclear if it was magma or hydrothermal fluid (super hot water) that was on the move. After the event the earthquake swarm has continued with smaller earthquakes with the largest as I write being M3.3.
Volcano forecast
Slysaalda station, image by Icelandic Met Office.
Last week I wrote an article about Grimsvötn where I described my favorite method of modeling the likelihood of an upcoming eruption, the finite element threshold analysis modeling method. It basically is a way to try to calculate how much pressure increase a volcano can take before it ruptures like an old boiler tank.
And like an old boiler tank a volcano will creak and groan as it closes in on an explosion and that the amount of creaks and groans will increase exponentially as the volcano closes in on an eruption. For Katla we do not know how much of the creaks and groans there will be prior to an eruption being inevitable.
I will here return to the known increase of magma influx from depth and the very sudden increase in energy released as earthquakes at Katla. In my view a volcano that suddenly changes its pattern is about to do so in more ways than just as being more seismically active. In my way of modeling this is exactly the kind of sign a volcano would give as it comes close to the breaking point that the model predicts.
I am certain that the volcano has reached the tipping point of no return. If things calm down now it will still be closer to an eruption and if it continues or intensifies it is only a question of a relatively short time before we get the steady thrumming earthquake swarm that we know from other Icelandic eruption run ups. Right now I would say that we are days to years away from an eruption, but if the activity continues or intensifies I would say we are days to weeks away. The change in behavior is after all that significant.
In 2011 Henrik Lovén wrote this; “While a larger “proper” eruption of Katla in the VEI 3 – 5 range cannot be ruled out, I find one unlikely at present as the current activity mostly is in areas already depleted of evolved magmas by geologically speaking very recent major eruptions. Also there is little sign of the uplift required on GPS. If one were to occur, the odds for one towards the upper end of what Katla is able of ought to be better in the Eastern to Northern parts of the caldera.”
This also follows the modeling prediction that the greatest likelihood of an eruption occurring in a part that has not recently erupted since the pressure there should be larger, a pattern that is known for the Icelandic caldera volcanoes.
In short, if I use my own model of prediction (and I should) it seems to say that Katla is nearing an eruption. Due to lack of data prior to an eruption I can’t calculate when exactly it will occur, but if the current swarm continues over an extended period or suddenly intensifies and continues we should see an eruption in the not too distant future.
For those interested in a more in depth explanation of the finite element threshold method I recommend my previous article about Grimsvötn.
CARL REHNBERG
Sunday
28.08.2016 18:41:23 64.636 -17.473 8.3 km 3.2 99.0 2.6 km E of Bárðarbunga
Sunday
28.08.2016 18:41:09 64.625 -17.447 4.3 km 2.8 99.0 4.2 km ESE of Bárðarbunga
May Clyde Tombaugh be looking down and
One of my Science Heroes …
His ashes are on New Horizons and on their way out to the Kupier
Belt…
http://www.space.com/19824-clyde-tombaugh.html
Let’s light the candle…
Small swarm on Myrdalsjökull:
Monday
29.08.2016 00:42:01 63.623 -19.148 1.1 km 0.2 82.97 5.3 km NNW of Hábunga
Monday
29.08.2016 00:41:23 63.609 -19.156 1.1 km 0.4 90.01 4.2 km NW of Hábunga
Monday
29.08.2016 00:39:06 63.605 -19.150 1.1 km 0.1 88.97 3.7 km NW of Hábunga
Monday
29.08.2016 00:37:06 63.611 -19.177 1.1 km 1.4 90.03 4.8 km SE of Goðabunga
Monday
29.08.2016 00:36:17 63.607 -19.166 1.1 km 0.7 90.01 4.4 km NW of Hábunga
Monday
29.08.2016 00:35:18 63.597 -19.165 1.1 km 1.3 90.07 3.7 km WNW of Hábunga
Source: http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/#view=table
IMO have checked the above out. Updated depths etc:
Monday
29.08.2016 00:42:01 63.630 -19.147 1.1 km 0.9 99.0 5.2 km ESE of Goðabunga
Monday
29.08.2016 00:41:23 63.611 -19.143 2.4 km 1.2 99.0 4.0 km NNW of Hábunga
Monday
29.08.2016 00:39:06 63.610 -19.161 0.1 km 1.0 99.0 4.5 km NW of Hábunga
Monday
29.08.2016 00:38:14 63.616 -19.173 0.1 km 1.9 99.0 4.6 km SE of Goðabunga
Monday
29.08.2016 00:37:06 63.615 -19.174 0.1 km 1.7 99.0 4.6 km SE of Goðabunga
Monday
29.08.2016 00:36:16 63.612 -19.150 0.1 km 1.6 99.0 4.4 km NW of Hábunga
Monday
29.08.2016 00:35:17 63.615 -19.158 0.1 km 2.4 99.0 4.8 km NW of Hábunga
Source: as above.
Heads-up… Katla.
One star already…
Three? now and one nearly:
Monday
29.08.2016 02:03:38 63.658 -19.123 1.1 km 0.9 43.91 6.6 km ENE of Goðabunga
Monday
29.08.2016 02:03:22 63.656 -19.158 1.1 km 1.2 90.03 4.9 km ENE of Goðabunga
Monday
29.08.2016 02:01:06 63.648 -19.080 1.1 km 1.7 90.11 7.6 km N of Hábunga
Monday
29.08.2016 01:58:41 63.672 -19.181 1.1 km 1.5 90.04 4.9 km NE of Goðabunga
Monday
29.08.2016 01:54:34 63.641 -19.056 1.1 km 0.4 90.02 7.1 km NNE of Hábunga
Monday
29.08.2016 01:51:08 63.642 -19.084 1.1 km 2.1 90.1 6.9 km N of Hábunga
Monday
29.08.2016 01:49:58 63.566 -19.239 16.2 km 0.7 32.76 7.0 km WSW of Hábunga
Monday
29.08.2016 01:47:28 63.644 -19.060 0.1 km 3.1 99.0 7.4 km NNE of Hábunga
Monday
29.08.2016 01:47:02 63.655 -19.086 0.1 km 3.1 99.0 8.2 km ENE of Goðabunga
Monday
29.08.2016 01:45:56 63.655 -19.096 0.1 km 2.9 99.0 7.8 km ENE of Goðabunga
Monday
29.08.2016 01:45:34 63.628 -19.105 1.1 km 0.8 83.12 5.3 km N of Hábunga
Monday
29.08.2016 01:44:32 63.626 -19.103 1.1 km 1.8 90.07 5.1 km N of Hábunga
Monday
29.08.2016 01:41:37 63.656 -19.087 0.1 km 3.1 99.0 8.2 km ENE of Goðabunga
Continuation of the swarm noted above. Not all have been confirmed. But note the three 3.1s, a 2.9 all at shallow depths and one small eq at 16.2km.
Does Carl have to look for edible hats?
I don’t think so… no strong HT.
An HT would appear before magma broke through the ice-cap?
Depends on the scale of what happens and how close to the surface eruptible magma already is – and to a degree its composition. HT is the signal of magma *moving*…
Moving or gas bubbles bursting?
Moving generally. There’s a limit to how much gas can come out of solution while still pressurized. And that’s where magma composition comes in too of course. There’s a cryptodome in Goðabunga – and Katla is capable of cooking anything from basalt to rhyolite.
Not sure how many of those were purely tectonic.
Someone is busy at IMO: one of the above eps has been upgraded to a 3.0.
Monday
29.08.2016 01:44:32 63.654 -19.080 0.1 km 3.0 99.0 8.2 km N of Hábunga
So four 3.0 or more and one 2.9.
They look a little bit more wet, but I’m no seismologist. With that said, this has the appearance of starting a run up to an eruption.
Definitely more noise than I ever remember seeing at Katla, although there is no stack – everything is on the surface. That typically screams to me that this is some sort of phreatic event, but the scattered locations throughout the caldera suggests it’s not the product of a localized phreatic event. Also, this is already more vigorous than any phreatic event we’ve seen at Katla, including the 2012 event.
There are non-crazy people who tend to believe the 2012 event was a small subglacial eruption.
Katla twitched a bit before the 2014 activity at Bardarbunga which preceding the Holuhraun eruption. But not as much as this, from memory. Other than the fact they are both near the MAR there is no immediately obvious link.
I think there’s more going on in that corner of Iceland – the Eyjafjallajökull – Vestmannaeyjar – Katla triangle I’ll call it – than meets the eye.
Micro plate?
If you squint at the IMO maps, the eps are forming either a ring or two lines. If the latter, activity would be on two rifts. I’ll try to plot these later today but if anyone else can do so sooner, feel free.
GFZ, reporting 4.7 Iceland, is she waking up?
Released from the pending queue. Once released, further comments should appear without delay
USGS, said, 4.6
One of the Katla eps has been upgraded:
Monday
29.08.2016 01:47:28 63.644 -19.063 0.1 km 4.9 99.0 7.3 km NNE of Hábunga
Source: http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/
& now downgraded but the one before it has been upgraded – both over 4 ‘though.
Tremor graph for reference. I really can’t discern if this was a large phreatic event, or something more significant. I believe if magma were moving around, we would see higher tremor on the red band, but I’m not positive on this, and it could only be the start of something more here.
Think a couple of the other stations are livelier: SLY and RJU, from memory.
Katla seems a bit restless. Maybe she is still ticked off at Barði.
http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/
For whatever it’s worth, they were nearly 5.0 quakes.. That’s a very large quake in Katla, with the one being 4.8 magnitude. It’ll be interesting to see what shows in the morning when the sun comes up.
Edit- Readjusted to a 4.5. Still quite large for Katla.
Kata should be visible on the webcams fairly soon now. But the magnitude of the 1:47 eqs is changing. Wonder if they were felt in Vik or anywhere else near Myrdalsjökull? OTH most people would be asleep then.
She’s visible on the Mila cam now. The picture is still fairly dark but nothing abnormal so far. There is a small cloud in front of the glacier which may indicate warmer water coming from under the glacier but really too soon to tell with any degree of certainty.
Yeah, quake activity seems to have stopped too based off of the drum plot.
Karen & Ross beat me to it. Katla looks like she took exception to my comments about her sulking!
I am looking out for comments about sulphur smells coming from the rivers as happened in July’s hlaup
Certainly increase in activity this morning. Keeping an eye on her.
You can get a good view on the Katla Mila Cam now. Looks very calm. Even the small cloud has gone. 🙂
The two largest is now 4.5
01:47:28 63.644 -19.063 __ 0.1 km __ 4.5 __ 99.0 __7.3 km NNE of Hábunga
01:47:02 63.653 -19.089 __ 3.8 km __ 4.5 __ 99.0 __8.1 km E of Goðabunga
Translation of the text I found on RUV (Iclandic radio and tv): Tonight at 1:41 began earthquakes north of the Katla caldera. Two earthquakes of and over four levels and a few of the three points. A dozen earthquakes have been followed. No turmoil (I wonder if that should be tremor) is visible along these earthquakes. The strongest earthquake felt in the hall in Langadal.
In responding to a previous comment by Albert ,I got to thinking about the possibility that the biology in rivers and other ground water systems may change prior to an eruption due to the change in the chemistry or temperature of the flow from the potential eruption site. I couldn’t find any data as yet but I did find this interesting article that could be used to predict an eruption.
http://onlinelibrary.wiley.com/doi/10.1029/2000GL012467/full?scrollTo=footer-citing
The problem with Icelandic predictions in this instance,
is of course the fact that most of the volcanoes there are under glaciers. . Water that emerges from under the icecaps prior to an eruption has a sulphurous smell and is an indication of geothermal activity somewhere towards the source of the stream. I would be interested to find out if, as the temperature rises, bacterial growth increases. I Just a thought.!
someone can post the link for the live drumplot near katla?
http://hraun.vedur.is/ja/drumplot/mapDRUM.php
ty
Last update: M4,5 and a M4,6 Getting bigger and bigger.
The specialist remark:
“This night at 01:41 started an earthquake swarm within the Katla caldera. Two earthquakes were over M4. The largest earthquake occurred at 01:47:02 M4.5 and another one 20 seconds later, M4.6. The largest earthquakes were felt in the area. These are the largest earthquakes in Mýrdalsjökull since modern instrumentation. About 20 aftershocks have been recorded. No tremor has been seen.”
http://en.vedur.is/
They’re now both even classified as 4.9 and both are pretty shallow.
Check out Katla webcam http://www.livefromiceland.is/webcams/katla/
Not sure what it is, steam or smoke.
Might just be clouds… but it does look quite smokey! Maybe Katla is having bacon for breakfast?
Since we have some more on the left I think it’s only sheepy clouds…
If there is any kind of significant eruption you will NOT be wondering ‘are they clouds or not?’…!
Absolutely nothing happening on the webcam. Icelandic news reports that the quakes last night were the largest in the era of modern measurements. What that means exactly is unclear but they are at least bigger than anything seen in several decades.
Had to double check when I saw the name… Almost go confused for a moment.
To quickly and wildly speculate: 1. Eruptions are often preceded by a significant earthquake, months or more before anything happens. Perhaps this series presages a future -but not imminent- eruption. 2. Iceland objects to being upstaged by Pluto.
Maybe katla’s earthquakes draw three parallel lines.
Is there a underlying geological meaning?
The question is if these quakes are tektonic or volcanic by nature…so far there has been no tremor recorded. It would be very interesting now to know what preceded the 1918 eruption.
For anyone new to VC or Icelandic volcanoes here is a handy summary of Hekla’s activities.
I think the first precursor would be local farmers noticing an increase in the smell of sulphur in groundwater (Streams & Rivers) and increasing tremors.
After the Eyaf eruption it was expected that Katla was to erupt within months. This didn’t happen ….unless there was a small eruption beneath the icecap that created a joKulhlaup.
if she does erupt then expect major disruption to Icelanders and beyond. The latter depending on wind direction and other factors. There is a great possibility of danger to livestock and humans.
http://www.icelandontheweb.com/articles-on-iceland/nature/volcanoes/katla/
The earthquakes immediately preceding the 1918 eruption are described as having been pretty intense in the nearby communities but still not so powerful that they caused any damage.
Very nice Pluto post! Curious to get more!
This is a small recount of the eruption in 1918, in Icelandic. It says on the 18th of Oct. People felt a sharp earthquake and booming around the country. The volcano erupted for 24 days
http://arid1918.wikispaces.com/K%C3%B6tlugos+%C3%A1ri%C3%B0+1918.
wow. 4.9 now
Thanks, Albert. Nice read on a favourite topic.
Well, so it’s all eyes on Iceland. Will be interesting how the next days/weeks/months (?) progress at Katla. Looks like another micro quake from Lady H too. Exciting times!
Hi Inannamoon. I agree that Albert’s post is fascinating. I omitted to say thank you to him have omitted to add my thanks because Katla sidetracked me!.
I am not too knowledgeable about space and struggle with comprehending distances especially. However the posts have ignited a serious interest shared with my step-son who explains lots to me.
I never seem to cease the learning process and wish I had this knowledge when I was much younger! I am frustrated that my life will not be long enough to learn more and to “see what happens”! Does anyone know where the fountain of youth is situated ?
Hi Diana, if I find it I’ll let you know 🙂
At times I am astounded by how much we are still learning about our terrestrial home, let alone the solar system and beyond! It’s exciting to think of what we don’t know yet that’s waiting to be discovered.
As a kid growing up I was always intrigued by, as it was known at that time, the missing 10th planet, Planet X. Now I’m lucky enough to be around as new discoveries are made.
Perhaps Planet X is where we’ll find the fountain of youth, created by the passing of a rogue planet millions of years ago.
P.S.
Good to have you back, Diana
TY 😀 How much is a return ticket to Planet X? and do they do sebior citizen concessionary fares ? 😀
Out of interest the latest quakes seem to be going deeper.
http://hraun.vedur.is/ja/Katla/myr_allt.html
The conductivity of some rivers running off Myrdalsjokull has been quite significantly increased since 25/8-ish, if I am reading the data correctly – eg Skalm, Mulakvisl, and upstream on Markarfljot.
Doesn’t seem to be any changes just yet after last night’s eqs, but it may still be too early to show.
A M7,0 at the South Atlantic ridge, a M5,1 at the mid Atlantic ridge..
http://earthquakes.volcanodiscovery.com/
Map with latest quakes
https://vatna.carto.com/viz/2cf646df-b2e8-4f17-be6d-bff452e6a4ca/public_map
Quick take on this swarm is it looks different than Katla swarms in the past which are typically scattered all over the caldera.
This looks like first a line along the SW edge and the along the NE edge of the rim. They look to me to be quakes caused by stress on the caldera faults, from what one can only speculate.
FYI
This map goes up to 0500GMT August 29th
Thank you. Interesting pattern. It looks like two W-E aligned faults. OTH I read somewhere that Katla’s eruptive fissures in the caldera were N-S alignment, but I could be wrong.
No. Got that one wrong 😳
Katla’s intracaldera fissures are SW-NE and E-W trending.
Source: https://www.researchgate.net/profile/Bergrun_Oladottir/publication/235956947_The_Katla_volcano_S-Iceland_Holocene_tephra_stratigraphy_and_eruption_frequency/links/0deec515aa4f00d7b9000000.pdf
Monday
29.08.2016 11:23:37 63.659 -19.152 0.7 km 2.6 99.0 5.3 km ENE of Goðabunga
For avoidance of doubt: can some sketch on a map and a x-section where exactly this Goðabunga cryptodome is supposed to be…? Thanks!
M3.1+ quakes since 1995
07/16/1995 3.14
04/01/1996 3.17
04/01/1996 3.17
08/09/1996 3.33
08/10/1996 3.54
09/29/1997 3.17
03/26/1998 3.46
03/27/1998 4.57
07/20/1998 3.86
07/20/1998 3.57
09/07/1998 3.12
10/24/2000 3.67
04/27/2002 3.25
06/20/2002 3.27
10/28/2002 3.4
09/22/2003 3.89
07/02/2004 3.94
07/02/2004 3.94
12/22/2004 3.27
12/22/2004 3.27
11/02/2008 3.17
07/16/2009 3.11
06/18/2014 3.17
07/15/2014 3.1
02/21/2015 3.33
09/22/2015 3.26
07/26/2016 3.19
07/26/2016 3.16
08/19/2016 3.48
08/29/2016 4.45
I am feeling a bit sorry for Albert here.
Iceland in general seems to oppose his article on Pluto. First it was postponed for activity in Grimsvötn, and I now fear that it will be a bit shortlived due to Katla.
Later this evening there will be an article on Katla that explains what is happening in detail. For those who like to keep track of things, this will be my first piece on Katla due to it being the first time that particular volcano does interesting things. And yes, I am brushing up on hat recipes.
Albert’s post has been shared by me with step-son…….I am sure Albert understands that Volcanoholics are desperate for a fix and as soon as the initial feeling of well being returns they will calmly realise what a fascinating little planet Pluto is and…Where did it come from, how and why? Only partial answers it seems. lots to learn yet.
Really minor point: Albert has not signed his excellent post (unless there is something wrong with my screen 🙂 )
Thanks. He has now.
This is a public service announcement for all webcam watchers:
Exactly, there will be 10 to 35 km high mushroom cloud, darkness, ash everywhere, equipment going offline, Icelanders selling ice cream at pre-determined lookout spots to tourists. In other words, it will be an event that goes well with the more pompous parts of the Ring of the Niebelungs (Götterdammerung).
I’m looking at the pictures on a mobile and the bottom photo doesn’t appear to show any activity. Maybe pay off the image is cropped or the photos are reversed on mobile?
Click the picture, it should then show ok.
In the bottom photo the entire bloody sky is black as the ace of spades; that’s the eruption column! A few minutes after that frame grab the entire frame was black as if it was night!
Hello from Germany !!!!
Where can i find this webcam to watch the Katla???
Thanks for a reply
Greetings and salutations from Scotland
http://www.livefromiceland.is/
Thanks a lot !!!
You can now access all NASA research papers for free, there’s bound to be some volcano related stuff there http://www.iflscience.com/space/you-can-now-access-all-of-nasas-research-online-for-free/
Hi Albert, thank you for the interesting article on Pluto 🙂
Well maybe 2016 won’t be a quiet volcanic year after all…
Thanks to 3d Bulge for these shots (http://baering.github.io/earthquakes/visualization.html):
https://drive.google.com/file/d/0B0Ga9jbjSMhfRWZ4OEUxcnhtbnc/view
https://drive.google.com/file/d/0B0Ga9jbjSMhfc3Z6MUcyVk5qdjg/view
The last plot shows the big quakes to be one the side where the mountain is steepest. Is that correct? If so, it is an important piece of information. The shallowness of the quakes means that surface topology is relevant. Has there been slippage on that side?
Comparing topographical maps with a map specifically of ice features, it looks to me from the lat/long data that the biggest quakes are situated towards the eastern edge the summit plateau of Myrdalsjokull where the ice is not sloping very much. They are not on the glaciers that flow from the central plateau. Also, and again as far as I can work out from the glacier maps, they on the same ice mass.
So perhaps not an obvious location for basal ice slippage on the basis of topography (as our discussions last week might lead us to infer). If the quakes were on different ice masses, that would I imagine reduce the likelihood of the quakes being related to ice movements.
I wonder what magnitude icequakes such as we were discussing last week can reach. Also relevant is the thickness of the ice in the area we are looking at.
“on the basis of topography” – I think I must have meant “on the basis of topology”!
Ice caused quakes are generally small. Below M2.
Thanks, and thank you for a very interesting article, too.
Updated with latest information from IMO
Also, Albert as usual the best reading on the internet!
https://vatna.carto.com/viz/2cf646df-b2e8-4f17-be6d-bff452e6a4ca/map
You may have to refresh to get the updated version
https://vatna.carto.com/viz/2cf646df-b2e8-4f17-be6d-bff452e6a4ca/public_map
Katla has another star on her this morning.
Monday
29.08.2016 15:12:45 63.656 -19.160 0.4 km 3.3 99.0 4.8 km ENE of Goðabunga
This one is a good bit further west.
But still in the area of the Katla activity. Shallow again. The deeper quakes (not very deep) are all in the northeaster cluster. (Apart from one quakes with a depth of 25km which i assume is a reflection signal rather than a real quake down there).
And in other news, a hurricane is approaching Hawaii and should pass just south of the main island on Wednesday. There may be a risk of torrential rain for Kilauea and Mauna Loa – think tsunami but coming down the mountain rather than up the beach. The waves could make shore collapses more likely but you shouldn’t be there anyway during a hurricane. Another hurricane is scheduled for Saturday but may pass north of the Hawaiian islands.
And another storm is heading for Lurking for Thursday.. I’ll be enjoying the warm Manchester sunshine!
I’m getting a kick out of watching our local weather twit mess up her lines. The “storm” is still having a lot of difficulty getting the storms over the central rotation. They bloom over Cuba and rain out before they can contribute to the strength.
The current GFDL model has it nailing Panama City. Tate’s Hell is probably gonna get wet. Which is okay, it’s what that ecosystem is made from. The hominids living around there might not like it.
Yeah, our local yahoos are going bat-guano crazy here as well (Lowcountry, SC), with Gaston going “fish” around Bermuda, the little thing off to our north, and the one brewing around The Big Bend you referenced above.
Just as long as we do not get the amount of rain we did last October (my Flickr album for it: https://www.flickr.com/photos/laconicphotog/albums/72157663242177624), we should be just fine.
The article has now been reposted as a dual article with Alberts original article on Pluto and a new part that is about the Katla unrest.
http://www.volcanocafe.org/pluto-the-big-hearted-dwarf/
I am surprised that I could invent a predictive model that gives a result contra my own intuition like this. The good thing with science is that it shaves you quite close when you just assume instead of doing the work proper.
And yes, I have a new recipé for BBQed hat.
The thing that had started to pique my interest earlier in the year at Katla was the increase in deep earthquakes. I’ve noticed this year, that two volcanoes specifically have seen a notable uptick in deep quakes, with the first being Katla, and the second being the Askja system. Askja has gone quiet over the last 1-2 months, but Katla has kept chugging along.
Carl, do you have any thoughts on the alignment of the earthquakes? There are two pretty clear lines on the quake map, likely following faults or regions of a ring fracture. All of the green stars are on the north end, but I think the presence of the second line is really quite interesting.
I think this could maybe suggest an inflation point that is somewhat between the two regions, although more northerly focused judging by intensity.
As a final note for people, Katla HAS been inflating for years at a pretty constant rate. The problem here, is that there is not real historical data we can go off to compare the inflationary data to past eruptions.
I think that it could indeed be a representation of the outer edges of an inflating reservoir that is made manifest by two faultlines. But that is a guess on my part.
In regards of inflation, few Icelandic volcanoes suffer from a burst of inflation prior to eruption. Slow and steady is the pattern for most of them. I know that CBUS knows this, my comment is more for all new readers.
I find the quake pattern of +20km deep shows the possible path of the feed for any possible inflation?
This map shows the latest swarm in red and the quakes that are deeper than 20km(since 1995) are in blue.
Click on the blue quakes to get the specifics including date, hover over the red quakes will give you Depth and Magnitude
https://vatna.carto.com/viz/b862bcad-fb04-4b10-8b34-d5d433ffd377/public_map
Seems like there might be a conduit leading up to where the two big ones happened. Hard to see in top down 2D.
I have looked at the 3D shape and it looks like an wedge shape (pointed side down) that runs East to West starting around 30km deep running the length of the swarm show in blue.
Suspected as much. Thank you for clearing that one up for me.
Double yummie article! Thank you Albert and thank you Carl for a great read!
I’ll be overflying Iceland ( or quite close to it anyway) a few times in the next couple of weeks.
Then again, maybe I won’t if Katla erupts…
Exciting!!!
Hopefully we can stay on top of an eventual upcoming eruption.
I feel that I should clarify that both of my latest articles represent the point where my modeling states that an eruption is inevitable and start to be possible to put a “when” on. It is not statements that an eruption will follow in the next few days necessarily.
Even if the current action at Katla is tectonic, Katla may have a shallow magma chamber at 3km (alternative theory is that this is caldera infill) so fault movement may provide a path for magma ascent sometime in the future.
Katla has had a the occasional deep earthquake over the period I have been watching Iceland’s eps and no doubt many before so magma may have been “quietly” ascending, albeit slowly over some time.
As an addendum to the brief mention of GPS inflation, here is a chart to help illustrate the gradual inflation that has occurred at Katla.
And for those that are new in here.
This shows how much the annual Ice melt affects the GPS trajectories.
Press have picked up the story:
http://www.independent.co.uk/environment/iceland-volcano-katla-eruption-ash-cloud-warning-alarm-biggest-tremors-earthquakes-40-years-a7215111.html
I have updated the article with a plot that shows the large effect the twin M4.5s had on the Cumulative Seismic Release.
Those two earthquakes released 1.5 times the amount of energy compared to all other registered earthquakes. Quite a whopper…
Deep quake energy has been rising in the last couple of years as well
Nice plot, mine was to uggly to publish 🙂
And then a star at Grindavík
Monday 29.08.2016 17:51:28 63.869 -22.445 4.2 km 3.4 99.0 3.4 km N of Grindavík
Using Ian F’s CartoDB graphs, I was able to work a little bit of magic to better visualize the earthquakes beneath the Glacier.
Earthquake locations (based on Iceland historic data)
Earthquake Cloud & Density Representation.
I hope the second image here can better reveal some of the tectonic structures beneath the glacier. I wouldn’t be surprised if one or more of these represent a nested caldera structure that is hidden beneath the ice cap. Alternatively, they could just be focal points for earthquakes, or possible resurgent dome structures, or something altogether different.
The grey western blob is Godabunga, the other are known spots of previous eruptions and may indicate individual magma reservoirs.
Excellent maps, thanks!
Discounting Godabunga (which lies outside the Katla Caldera) there are three major centres of activity. The most southerly one is the location of the 1823 and 1918 eruptions, the westerly one the 1755 eruption. Because it takes a very long time to “cook” the evolved magmas, the best bet for a major, explosive eruption is the third locus under the name Myrdalsjökull (or possibly one of the other three, minor loci in the northern part of the caldera).
Yes, that really highlights the “soft” spots and I am thinking the same as Henrik when it come to the most likely spot
Even if Katla does not erupt from this event, might be worth your while checking your volcanic eruption DR plans now or when she or one of her friends does.
Albert, I got this comment on FB in regards of your article.
“Marc Byrne: Pluto’s radius is said to be 2370 km in the article, but this should say ‘diameter’.”
Funfact regarding Pluto, Russia has larger surface area.
Good catch, now fixed. It was actually correct later in the sentence when it said ‘across’, but radius was most certainly wrong.
What a fantastic article Albert, thank you! I really look forward to part two, especially as it will the be possible to make a comparison of what we can deduce and how accurately from deep down the Sun’s gravity well. Is there any research done on such comparisons between “Earth-based” observations and robotic forays into the unknown?
People are advised to keep a distance to Múlakvísl due to high gas levels.
“Glacial water is flowing into Múlakvísl river, south of Mýrdalsjökull. Increased conductivity has been measured in the river and gas measurements in the area show high concentrations of sulfur dioxide and hydrogen sulfide. People are advised not to travel near the river, due to gas pollution. It is not uncommon for glacial water to flow into Múlakvísl, causing increased conductivity and gas pollution.”
The IMO report also mentions the northern side:
“According to local reports, the level of the Bláfjallakvísl glacial river is unusually high. Bláfjallakvísl originates from the northern side of Mýrdalsjökull and people are advised to show caution when crossing the river.”
The earthquakes may have released melt water from underneath the glacier.
The increased water output on the north side of Myrdalsjökull has been ongoing for a few days and precedes this morning’s eq activity.
New warning from http://en.vedur.is/#tab=vatnafar
Glacial water is flowing into Múlakvísl river, south of Mýrdalsjökull. Increased conductivity has been measured in the river and gas measurements in the area show high concentrations of sulfur dioxide and hydrogen sulfide. People are advised not to travel near the river, due to gas pollution. It is not uncommon for glacial water to flow into Múlakvísl, causing increased conductivity and gas pollution.