Vatnajökull and the volcanoes under the glacier in Iceland
Over on Jon Frimann's Iceland Volcano and Earthquake Blog, there has been a lot of talk about the activity under Vatnajökull (see map below), the largest glacier on Iceland and specifically near Grímsfjall/Grímsvötn. I thought I'd take a closer look at the great glacier of the island nation and specifically, the volcanic activity that occurs around and under the icecap (and then take my speculative stab at what might be going on near Grímsvötn).
Map of the Vatnajökull glacier, Iceland.
First things first: Vatnajökull is big (see below). Real big, at least as modern glaciers go. It covers 8100 km2 of the landmass of Iceland with a maximum thickness around 1000 m (1 km) thick, but the average thickness is closer to 400-500 m, leading to a rough estimate of the total volume of ~3300 km3 glacial ice. The glacier is still actively accumulating snow that will become glacial ice (after ~100 years) - almost 60% of the ice cap is still above what is known as the "equilibrium line altitude," which is ~1100-1300 m for Vatnajökull. This ELA marks the boundary between the zone where snow/ice is melted away each warm season (below the ELA) and where snow/ice doesn't melt, so it can accumulate year after year (above the ELA). The whole icecap actually pulsates throughout the year as the weather changes ~ remember, most glaciers actually have a large liquid water drainage system underneath them ~ so the elevation of the ice surface can change from 1400 to 1800 m. There are also a number of subglacial lakes under the icecap, likely produced by the high heat flow in that part of Iceland.
NASA Earth Observatory image of the Vatnajökull glacier, taking during the 2004 eruption of Grímsvötn.
Now, any glacier this large on an island as volcanically active as Iceland is bound to have a lot of subglacial volcanoes, so it should be no surprise that Vatnajökull has at least 7 identifying volcanoes under the glacier. The three most famous of the subglacial volcanoes under Vatnajökull are the aforementioned Grímsvötn, Öraefajökull and Bardarbunga. Öraefajökull, on the southern edge of the glacier, is the least active of the three, with its last known eruption in 1728 - however, that event was a VEI 4 - and the previous known eruption to that, a VEI 5(!), was in 1362. Both of these events were explosive eruptions. Bardarbunga is a part of a long fissure system that runs along the west side of Vatnajökull - in fact, it extends 100 km to the S and 50 km to the N of the glacier - and lies close to where the Mid-Atlantic Ridge comes on land in Iceland. Like many Icelandic volcanoes, it has a central caldera that then has fissures that radiate from it (the Veidvötn and Trollagigar fissures). Bardarbunga last erupted in 1910 but a number of unsubstantiated, small subglacial eruptions may have occurred within the Loki caldera over the last century. Most confirmed eruptions have been explosive eruptions that lead to lava flows and rank around a VEI 2, although the 1477 eruption from the Veidvötn fissure was a VEI 6 that produced over at least 2.5 km3 of basaltic lava.
Grímsvötn erupting in 2004 through the Vatnajökull glacier.
Finally, the most famous subglacial resident at Vatnajökull is Grímsvötn - not only is it one of the most active volcanoes on Iceland, but it also erupted as recently as 2004 (see above). Much like Bardarbunga, Grímsvötn is a central edifice on a long set of SW-NE trending fissures, a set of lineaments that produced one of the most significant historic eruptions, the 1783 Laki (Skaftar Fires) fissure event. The Laki eruption produced over 15 km3 of basaltic lava over a mere 7 months over 27-km of fissures (see below). The Laki eruption did produce significant changes to weather in the northern hemisphere due to the release of volcanic aerosols like sulfur dioxide and was the source of one of the first connections between volcanoes and climate made by Benjamin Franklin (although he incorrectly attributed the eruption to Hekla) - it tends to be somewhat tenuously linked to all sorts of world events at the time. Grímsvötn has also had a number of non-fissure eruptions, producing explosive eruptions and accompanying jokulhlaups in 2004, 1996-98, 1983-84 and many more over the last few centuries. Most of these eruptions where in the VEI 1-2 scale, so fairly small, although in 1902 and 1873, the volcano produced explosive eruptions that ranked upwards of VEI 4. Grímsvötn is also known to produce jokulhlaups that are not directly related to volcanic eruption, such as the glacial outburst flood this last fall, likely caused by a breach of a subglacial lake near the volcano.
Part of the Laki fissure system that erupted in 1783.
Now, in such a volcanically active area, it should be no surprise that there is a lot of oscillation in volcanically-related activity, such as seismicity and hydrothermal activity. This is because many of these Icelandic magmatic systems are getting a constant input of magma from depth, much of it stalling at different depths in the crust, or that magma from previous eruptions continues to cool in the volcanic systems. An important interplay under Vatnajökull is between the glacier itself and the rock below - with all the fissures and crustal lineament, the weight of the glacier can potentially cause some seismicity. Iceland is also a very seismically active area due to the presence of the active Mid-Atlantic spreading center, so many earthquakes are associated with the processes of spreading. So, how does one tell if one of these volcanoes might be headed towards eruption? Using Eyjafjallajökull as an example, we might expect to see signs of an eruption for years before an eruption - and that earthquakes related to intrusion of basalt magma might not lead to an eruption directly. By combining with other monitoring tools like inflation, GPS and hydrothermal activity, we can start to get a grasp on how likely an eruption might be - and even that might be dicey. One thing can be sure: a subglacial eruption under Vatnajökull is likely because we have seen so many over the last few centuries. We have even seen a number of these large-scale (>2 km3) fissure eruptions, including the Laki eruption, so another fissure eruption isn't out of the realm of possibility. None of these fissures have opened since the advent of modern volcano monitoring came about, so we really don't have a good grasp on the signs that will indicate a fissure eruption might be on its way.
So, what to make of the current activity reported at Grímsvötn: (1) it isn't surprising; (2) more likely than not, it will need to anything from no eruption to a small VEI 1-2 event; (3) it could also lead to a larger fissure event, but right now there isn't any strong evidence that suggests it will. Iceland is a very volcanically-active region, so we should expect a lot of "noise" - lots of earthquake swarms, inflation/deflation, changes in hydrothermal activity - that is unrelated to an impending eruption. This makes the job of volcanologists in Iceland all the more difficult to discern the true volcanic signal from the noise of an active island.
Top left: A view of Vatnajökull from Höfn. Image by Flurin Juvalta.
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A vertical map might better represent a world dominated by China and determined by shipping routes across the iceless Arctic.
- Europe has dominated cartography for so long that its central place on the world map seems normal.
- However, as the economic centre of gravity shifts east and the climate warms up, tomorrow's map may be very different.
- Focusing on both China and Arctic shipping lanes, this vertical representation could be the world map of the future.
The world, but not as we know it<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg1NS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNTkwMjIyNn0.qmQfwUdjQka8JX6q4KGANagleiuucpWay5ytMenZxUU/img.jpg?width=980" id="b95e4" class="rm-shortcode" data-rm-shortcode-id="ac088ec55c0585a93a9a310faab9a4c7" data-rm-shortcode-name="rebelmouse-image" />
A Chinese 'vertical world map,' showing the world in a different perspective from the one we're used to.
Image: Prior Probability<p>Europe is tucked away in a corner, an appendage of Asia dwarfed by neighboring Africa. North America is stood on its head, facing the rest of the world from the top of the map — cut off from South America, which cuts a solitary figure at the bottom. Africa is justifiably huge, but equally eccentric. </p><p>The eye scouts elsewhere for a place to land: not the Indian Ocean, which dominates the middle of the map, but some terra firma. Antarctica and Australia are too small, mere stepping stones for the land mass of Asia. Ultimately our gaze is drawn toward China, the lynchpin of this unfamiliar world. </p><p>Managing to leave both poles intact, this "vertical" world map is about as far away as you can get from the classic Mercator projection – which slices up both, giving center stage to a puffed-up Europe. Perhaps this new map will become more familiar soon: It may do more justice to the world of the near future, dominated by China and determined by shipping routes across the iceless Arctic. <br></p>
China's 'ten-dash line'<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg1Ni9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NTI4MzQyNn0.sBe0oFTif4Jef1vWh1kAnUylU_QMPXT5xQjm-5aA3sA/img.jpg?width=980" id="a3b81" class="rm-shortcode" data-rm-shortcode-id="80fc6e4f5c9c1c978f698be2c8de5484" data-rm-shortcode-name="rebelmouse-image" />
'China without any part left out': includes Taiwan and the islands and atolls in the South China Sea, surrounded by a ten-dash line
Image: Global Times<p>While there's no indication that this map represents the Chinese government's "official" worldview, it is no secret that China has a thing with maps – and more specifically, the country's representation on them. </p><p>In China, the country's current economic success is seen as a redress of the unequal treatment meted out by western superpowers in the 19th century. China's world dominance is a return to a more natural state of world affairs, many feel. Cartographic rectifications are a symbolically significant corollary of that sentiment.</p><p><a href="https://www.citylab.com/equity/2015/12/china-cracks-down-on-politcally-incorrect-maps/421032/" target="_blank">Fines are regularly imposed</a> on companies – domestic and foreign – that fail to represent China to the fullest extent of its external borders, disputed though they may be by others (e.g. India, Taiwan and any of the countries with claims overlapping China's in the South China Sea). But the People's Republic's cartographic obsession doesn't end at China's territory itself. It also includes the country's position on the world map. <br></p>
The Kingdom at the Middle of the World<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg2MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyOTkwODEzMX0.SGrAZBH6iJVggFYSaIahzv9GvfEh17y1SwUNINbVicQ/img.jpg?width=980" id="1774c" class="rm-shortcode" data-rm-shortcode-id="99790d80a909d17a948f7c5d463d7d98" data-rm-shortcode-name="rebelmouse-image" />
Early Japanese color copy of Ricci's world map
Image: public domain<p>China's name for itself is <em>Zhōngguó</em>, which means 'Central State' or 'Middle Kingdom', reflecting its ancient self-image as the civilized center (<em>Huá</em>) of the world, with wild tribes (<em>Yí</em>) at the edge. That view is not unique to China. Vietnam, for example, at certain times also styled itself as the "central state" (<em>Trung Quóc</em>) – considering the Chinese in turn as the uncouth outsiders.</p><p>It may be surprising to recall, but Europeans themselves once considered their own continent a relative backwater, viewing Jerusalem as the true center of the world. That changed with the Age of Discovery, which placed Europe at the center of an ever-expanding world. Maps reflected that worldview, and largely continue to do so. That's why today's standard world map still has Europe at its center – with China off toward the periphery on the map's right-hand side. </p><p>The most notable feature of the very first major modern world map produced in China, the <em>Kunyu Wanguo Quantu</em> (1602), is that it places China firmly at the center of the world. Produced for the Chinese emperor by Jesuit missionary Matteo Ricci, it was the first map ever to combine that perspective with modern western knowledge: it was the first Chinese map to show the Americas, for instance. </p><p>That representation may not have taken off elsewhere, but it will be instantly recognizable to Chinese students, as it's the standard format for world maps in China's schools today.<br></p>
America on its head<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg2My9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYwMzQ5NTc0MH0.EqadI2Yp-2dPwi3VccFZelIDK4V9t0ZOfTfHjdB6wVw/img.jpg?width=980" id="97104" class="rm-shortcode" data-rm-shortcode-id="2b66e8de389b3d736bc28e019e445cd0" data-rm-shortcode-name="rebelmouse-image" />
Upside down you turn me: North America on its head, in Chinese characters
Image: Prior Probability<p>For those used to "classic" Eurocentric world maps, Europe's marginalization may come across as a bit of an upset. America's new position on the horizontal Chinese world map is less jarring: It merely moves from the left- to the right-hand side of the picture. But then there's this vertical world map, which deals a similar blow to the American land mass: divided in two and pushed to the upper and lower edges of the map.</p><p>Unfamiliar? Sure. Shocking? Perhaps. Wrong? Not really. First off, no world map is totally right, since it's mathematically impossible to transfer the surface of a three-dimensional object onto a flat surface without some distortion. And since the world is a globe, where you center that map is a matter of purely subjective choice.<br></p><p>Those choices have historical reasons. Mercator's map was not specifically designed to put an inflated Europe at the center of the world. That was just a side effect; its main purpose was to aid shipping: Straight lines on the map correspond to straight lines sailed on the seas.</p>
By 2050, a completely melted Arctic could enable the Transpolar Passage, shortening trade routes between Asia and Europe and boosting business for Alaskan ports like Nome and Dutch Harbor.
Image: The Maritime Executive<p>The vertical world map, showing the relative proximity of China (and the rest of Asia) to Europe and (even the East Coast of) North America, has a similarly maritime <em>raison d'être</em>, or it will have by mid-century. <a href="https://www.maritime-executive.com/editorials/the-arctic-shipping-route-no-one-s-talking-about" target="_blank" rel="noopener noreferrer">Experts project</a> that by 2050 (if not sooner), the Arctic will be sufficiently ice-free to enable the so-called Transpolar Passage, i.e. shipping straight across the North Pole. </p><p>That would shave more than three weeks off a traditional sea voyage between Europe and Asia, via the Suez Canal – and even be significantly faster than other northern alternatives like the Northwest Passage (via Canada) or the Northern Sea Route (hugging the Siberian coast). Since ships would not need to go through locks or pass over shallow waters, it would also remove current restrictions on tonnage per ship. <br></p><p>The only country seriously preparing for such a future: China. None of the other Arctic powers is giving the Transpolar route any strategic thought. On the other hand, China's Arctic Policy document, released in January 2018, already matter-of-factly refers to the Transpolar route as the 'Central Passage' – one of several 'Polar Silk Roads' that China seems to want to develop. And they already have the world map to go with it.</p>
The Labour Economics study suggests two potential reasons for the increase: corruption and increased capacity.
Cool hand rebuke<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQyMTIyNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NjY1NTYyOH0.0MCPKN3If94mYCNf3mMNrnTvJXjXN_bKLhgk9203EXk/img.jpg?width=917&coordinates=0%2C0%2C0%2C0&height=453" id="1627b" class="rm-shortcode" data-rm-shortcode-id="6d76421ba1ea0de4b09956b97e80c384" data-rm-shortcode-name="rebelmouse-image" />
A chart showing prison population rates (per 100,000 people) in 2018. The United States has the highest rate of incarceration in the world.
Who profits with for-profit prisons?<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="97ac37e6c7f6f22ec130ea2d56871701"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/dB78NV2WpWc?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>The Labour Economics study suggests that privately-run prisons do convicts a few favors at the moment of sentencing. However, proponents of private prisons often point to other benefits when making their case. Specifically, they argue that private prisons reduce operating costs, stimulate innovation in the correctional system, and reduce recidivism—the rate at which released prisoners are rearrested and return to prison.</p><p>In regard to recidivism, the research is mixed. <a href="https://journals.sagepub.com/doi/abs/10.1177/0011128799045001002" target="_blank">One study</a> compared roughly 400 former prisoners from Florida, 200 released from private prisons and 200 from state-run facilities. It found the private-prison cohort maintained lower rates of recidivism. However, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1745-9133.2005.00006.x" target="_blank" rel="noopener noreferrer">another Florida study</a> found no significant rate differences. And two other studies—one from <a href="https://journals.sagepub.com/doi/abs/10.1177/0011128799045001002" target="_blank" rel="noopener noreferrer">Oklahoma</a> and another out of <a href="https://journals.sagepub.com/doi/abs/10.1177/0734016813478823" target="_blank" rel="noopener noreferrer">Minnesota</a>, both comparing much larger cohorts than the first Florida study— found that prisoners leaving private prisons had a greater risk of recidivism.</p><p>The research is also inconclusive regarding cost savings. <a href="https://www.hamiltonproject.org/assets/files/economics_of_private_prisons.pdf" target="_blank" rel="noopener noreferrer">A Hamilton Project analysis</a> noted that such comparisons are difficult because private prisons, like all private companies, are not required to release operational details. In comparing what studies were available, the authors estimate the costs to be comparable and that "in practice the primary mechanism for cost saving in private prisons is lower salaries for correctional officers"—about $7,000 less than their public peers. They add that competition-driven innovation is lacking as the three largest firms control nearly the entire market.</p><p>"We aren't saying private prisons are bad," Galinato said. "But states need to be careful with them. If your state has previous and regular issues with corruption, I wouldn't be surprised to see laws being more skewed to give longer sentences, for example. If the goal is to reduce the number of incarcerated individuals, increasing the number of private prisons may not be the way to go."</p>
What exactly does "questions are the new answers" mean?
- Traditionally, intelligence has been viewed as having all the answers. When it comes to being innovative and forward-thinking, it turns out that being able to ask the right questions is an equally valuable skill.
- The difference between the right and wrong questions is not simply in the level of difficulty. In this video, geobiologist Hope Jahren, journalist Warren Berger, experimental philosopher Jonathon Keats, and investor Tim Ferriss discuss the power of creativity and the merit in asking naive and even "dumb" questions.
- "Very often the dumb question that is sitting right there that no one seems to be asking is the smartest question you can ask," Ferriss says, adding that "not only is it the smartest, most incisive, but if you want to ask it and you're reasonably smart, I guarantee you there are other people who want to ask it but are just embarrassed to do so."