Recently, there has been a noticeable increase in the number of volcanic related shows on TV and I for one think this is a good thing, (despite what some may say are unscientific and ‘scaremongering’) and here is why: 1. As a young child these shows are what inspired me to study and investigate, so in my opinion these shows encourage the scientists of the future. 2. Its always cool to see amazing images of erupting volcanoes. 3. These shows are very good at explaining things so that everybody can understand them. 4. You get to see things which you may never get to see in real life.
Among other reasons!
It has also been refreshing to see shows which not only just focus on the eruptions themselves but human interest stories and looking at how volcanic eruptions effect the natural environment and animals which get caught up in them. For example I watched a recent show based solely on Octopuses (Octopi?) around Stromboli and how they have learnt/adapted to the hazard of falling blocks from eruptions. Despite the very cheesy opening sequence involving some form of leopard/cheetah jumping into a lava dome that then erupts with Hawaiian 'runny' (or low viscosity) lava, a series of programmes called "Life on Fire" has had some very good filming and fascinating looks at the animals which live around the volcanoes, such as birds who use hot ashed to hatch eggs and the effects of erupting Alaskan volcanoes on Salmon.
Having said this, I do take some exception to some movies, most of them on the budget movie channels, not to be named here but show things with ridiculous titles such as 'Monster Shark vs Giant Octopus' (Syfy channel...cough cough). I have unfortunately had the opportunity to stumble across a couple awful volcano related films. Saying this there are some good dramas, such as the BBC Docudrama 'Supervolcano'.
If you have any comments or disagree in any way, please comment, I am always up for a healthy debate (Keep it clean please).
Just a quick update post on the eruption of Popocatéptel in Mexico. The alert level has remained at Yellow Phase 3 although activity has subdued. Below is an image of the latest webcam taken from the CENAPRED website. We can still see clear steam emissions, although current ash content looks low. This is confirmed in the latest report on the eruption which states that in the 7 hours leading up to the report the eruption bursts were small with seven occuring during that time. An image of the largest of these bursts (at 800 metres high) is available here. There are also some photos of the eruption on the BBC website.
From a Cenapred webcam.
Have you ever wanted to step inside a volcano? This summer a tour company is offering the chance of travelling down into the magma chamber/lava tube system/shallow magma storage area of Thrihnukagigur volcano. This volcano was talked about in a post by Erik from eruptions at some point last year. Whilst there is some controvesy over what to call the area beneath the volano, there is no doubt that an opportunity for the general public to explore a feature such as this is brilliant and is something I would love to do myself! If any one can read Icelandic (which I can't I'm afraid!), there is a website here which gives some info and pictures and diagrams on the volcano and the area. There is some info on the volcano and the area in English here on the tour website. The video below gives a good overview of the size of the volcano and the gap underneath. I can't comment with any certainty on the matter having not visited myself (its always best to look at things in the flesh and be there, you get a much clearer picture and can make clearer judgements for yourself!), however I am going to put my 2 cents in about the crater itself anyway. As a cinder cone the type of activity at Thrihnukagigur volcano will be much like some of the episodes at Etna which have created cinder cones there over the years, and as such, present an interesting incite into processes below the surface during such events. The vivid colours inside the volcano demonstrate the high gas content and activity of the magma, further confirming the type of activity there. In certain volcanoes worldwide there are lava lakes and these can be seen to ebb and flow in height and activity, therefore we can accept that other volcanoes in similar situations will do this too and can often be seen as 'tide marks' of sort. It is certainly fortunate for us that the magma drained away (which there could be a few reasons why this happened) as we now have access to something quite beautiful and it does provide scope for research into the shallow plumbing systems of volcanoes. A while back this tour was featured in a TV program (National Geographic) and yes while some of these shows can be sensationalist (not all of them!) one thing they do very well is promote interest in the science behind them and encourage people to investigate further so they are not necessarily a bad thing. There are a host of video and even the National Geographic program on the website which are worth a watch if you have some spare time!
A while back I posted on the Hidden Journeys project and a journey along the cascades. Today I thought I would put a brief post up with a little about the region and on one of the volcanoes which isnt talked about as much - Mount Hood. The volcanoes of the cascades arise because of the subduction of the Juan de Fuca Plate beneath its North American counterpart. From Mount Baker in the north to Crater Lake in the south the hazards these volcanoes pose are assessed by the Cascades Volcano Observatory (CVO) across the states of Washington, Oregon and Idaho. The remaining volcanoes to the south are assessed by the California Volcano Observatory (CalVO) In general, the research focus has centred on St. Helens due to the large amount of available and collected data as well as its relative ease of access. However there are many other important volcanoes in the area which shouldn't be forgotten!
A USGS graphic to show the locations of the major volcanoes in the Cascades and when they have erupted.
 Image Courtesy of NASA: Mount Hood Mount Hood, pictured to the right, hasnt erupted since 1865 (although there are a couple of uncertain eruptions after this with the latest in 1907). Even though it hasnt erupted for over 100 years it still shows signs of activity from time to time - with events such as earthquake swarms beneath or near to the volcano and the instability of its slopes. A recent seismic swarm in 2002 allerted scientists to the possibility of volcanic unrest, however a study by Jones and Malone suggested that this earthquake was related to tectonic forces. Although they also stated that earthquakes situated directly below the summit could arise from volcanic unrest.
I recieved an email recently asking some questions about Katla and the sender has kindly let me post my replies to him. If anyone has any questions like this please feel free to use the contact form or post a comment! His email:
" About a year ago, Stephen Sackur said that 'when Katla blows, we're all going to suffer'. I'm not sure what he meant by that, but since then I've seen several articles claiming that a Katla eruption can also cause lung conditions and, through the melting of the jokulhlaups or melting the Greenland and polar ice sheet, through depositing an ash deposit over them, affect the salinity of the Atlantic current, changing the climate of the northern hemisphere, and causing crop failures. (http://bit.ly/xLx4sN) I've also read that an eruption could cause acid rain if the acid coating on the ash is removed by rain. (http://bit.ly/w8VDqN)I know the media like to exaggerate, but is it at all likely that we could 'suffer' in any way other than prolonged travel disruption?"
My ReplyI could certainly write a very long reply to your question but will make it as brief as I possibly can! As with any eruption, people with lung conditions or even lite asthma can be effected by even the smallest amount of voclanic ash in the air (as occured with the eruption of eyjafjallajokull in 2010), unless the eruption were to reach into the stratosphere (which is unlikely), the effect from gases/ash on populations would only likely effect Europe if there were the correct prevailing wind conditions. Any overall effect would likely be small and limited to already underlying lung conditions. Historically, Icelandic volcanism has had an effect on European health after the Laki fissure eruption in 1783, this released a large amount of Fluorine and caused widespread health issues (involving fluorisis - not an expert but can cause bone deformation/growth). However this was of a different eruption type than will likely occur at Katla. With regard to any other effect, any covering of ash on the Greenland ice sheet would likely be small, if you look at historical eruption sizes these are around VEI 4/5, about the size of St Helens, or more recently Chaitén. Would this change salinity of the North Atlantic Drift - I doubt it, the quantities involved would not be great enough, unless a positively huge eruption occurred (at least VEI 6/7+, which is unlikely in Iceland with this type of eruption). I assume your reasoning or sources reasoning comes from the fact that ice covered in black/grey ash will absorb more light and therefore heat up and melt more quickly. Can volcanic eruptions cause acid rain, in short yes they can, whether this is prolonged and to what extent depends on the length of the eruption and the distribution of gases/ash in any plume. With regards to the possible climatic effect I refer you to a comment by someone on a previous post of mine on Katla: http://www.volcano-blog.com/1/post/2011/12/katla-the-volcano-that-everyone-is-waiting-to-blow.html#comments which explains it better than I probably could. More sulphur dioxide in the atmosphere (particularly the stratosphere) can cause temperature regime changes which would affect crops, but again, unlikely on any large or majorly noticeable scale. In summary, there is always potential for global/regional effects from an eruption of Katla on a global scale, however whilst possible on the whole they are not probable.
Hidden Journeys is a website dedicated to exploring the world through the air using amazing and awe-inspiring images of fascinating and beautiful areas by the Royal Geographical Society (London). Recently the story of the passage along the Cascades was illustrated on a journey between the two cities of Denver and Seattle and the Royal Geographical Society kindly got in touch to show me the work and share information about the project which I thought would be good to share as well.  (C) Aaron Schmidt. Rainier and Adams through the clouds. By clicking along the scrolling images along the top and selecting the Cascade Mountains section you get through to a page with three sections of images on the Cascades, the famous 1980 eruption of Mt St Helens and a section on Mt. Rainier ( featured in an earlier blog post of mine), the towering volcano which rests above the city of Seattle like a sleeping giant. Each section gives a good overview of the region, the volcanoes and the most important features around them. A graphic in the first section demonstrates how important research and study is of Mt. St Helens, not just for its 1980 eruption, as eruptions at this volcano are typically more frequent than at other cascade volcanoes. I have included a selection of the images on this blog post (click on images to see larger versions), but to see the rest you will need to visit the site, I certainly recommend a visit! In my next post I will be talking more about the volcanics of the region and more about one of the relatively forgotten volcanoes of the region Mount Hood in addition to the importance of the volcanoes further south in the cascades which generally recieve less focus online and in the media but are equally as important and fascinating.
Image courtesy of NASA. The devastating impact after the lateral eruption of Mt St. Helens in 1980.
What is Geoinformatics?
Geoinformatics (sometimes referred to as geographic information science or GIS) is a term which has been given a variety of descriptions but generally it refers to data which has been collected through techniques such as remote sensing and which are finally analysed, processed and visualised on a computer. At first glance it may seem that geoinformatics doesn’t play a large role within volcanology, however when one delves deeper, there is a huge amount of research and literature combining geoinformatics practices to solve and present volcanological problems. In the past, volcanology was purely based on written observations, however with the advancement of technology the need for processing and more sophisticated analytical techniques has led to the incorporation of geoinformatics within volcanology. Some examples of application....mapping (particularly hazard mapping), monitoring and extra-terrestrial mapping/investigation. A perfect example of Geoinformatics and volcanology is the brilliant NASA Earth Observatory website (example image below), it is through the taking of images such as these that we know about eruptions of remote volcanoes. I am sure there are many more applications of geoinformatics within volcanology out there, this was just an overview of some of the most important! If you are interested to learn more, read this summary here.
Puyehue-Cordón Caulle on the 2nd February 2012 from the NASA Earth Observatory website.
On the 12th Januray a new vent opened at the Turrialba Volcano in Costa Rica.  Turrialba Volcano, taken by Eliecer Duarte (OVSICORI-UNA) (GVP) Turrialba Volcano, stands at over 3300m high and is characterised by Basaltic to Dacitic type lavas.
The initial fumarolic vent formation was caused by overpressured rock which then collapsed to allow gases and what people refer to as non-juvenile or material not from fresh magma to escape. A fumarole is a vent which emits steam, gas or potentially other volcanic material at high temperatures, generally ranging from 100 to 1000 degrees celsius. The openeing of this vent was caused by the breakdown of the rock material, typically, but not exclusively, volcanoes in humid regions such as Costa Rica are more susceptible to collapse. This is caused by acidic water eroding and weakening rock, which, when the correct pressure is applied is liable to collapse. This process can be sped up by a constant degassing volcano such as Turrialba currently.
I highly recommend watching this video of the area after the 12th January incident, there is also a very good summary of the event by the Costa Rican Volcanology and Seimsmology Observatory available here. The video below shows activity recorded on the 18th January as an ash and steam emission began on the volcano. With another Costa Rican volcano, Irazú, a new eruption was preceeded by the opening of several new fumarolic vents, however OVSICORI-UNA have stated they do not currently believe a new eruption is expected soon, however they do state that Turrialba is an active volcano and the situation could change quickly due to its constant degassing state.
Katla lies beneath the Mýrdalsjökull ice cap and has height of approximately 1512 m. Katla has been showing increasing signs of unrest for many months now with periods of harmonic tremor prompting news reports of an impending eruption. Also, historically, an eruption of the Eyjafjallajökull volcano is often followed by one at Katla. However some of these news reports are citing the global impact an eruption may have. As a result I have a couple of comments about a recent BBC article titled New Icelandic Eruption Could Have Global Impact. First of all due to the high latitude of the volcano,a 'global impact' is unlikely, the majority of eruptions which transport ash globally and affect global temperatures are closer to the equator and if you look at past eruptions of Katla, the largest they reach is VEI 4/5 which is large, but not on the scale which Tambora or Pinatubo were. It is possible that ash will be transported through Europe again, although there are a number of factors which affect the transportation of ash other than wind direction, including ash particle size and strength of the eruption so even this isn't certain! One of my main gripes, it is very unscientific and bad practice to say a volcano is overdue! Its seen with Yellowstone all the time, its not acceptable there so it isnt for Katla either!  Steam rising over the Mýrdalsjökull ice cap. One of the major hazards from volcanoes such as Katla which lies beneath the Mýrdalsjökull ice cap is the jökulhlaup. These occur when an ice cap/glacier is heated from below, these events are usually triggered by a sub-glacial volcanic event. Such an event occurred on the 9th July from the Mýrdalsjökull ice cap and was likely trigger by an increase of heat flux from the caldera or a small sub-glacial eruption, this is a further indication of activity beneath the surface of Katla. There was also an episode of this kind in 1999. I confess that I am not the first one to write about this, but I felt the point needed to be made that caution should be taken when reading articles making claims such as the BBC article. So to summarise, Katla is showing signs of an eruption, with periods of harmonic tremor indicating the possible movement of magma beneath the caldera, however Katla will go when she wants to go!
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