Ask Me Anything: Reddit quizzes volcanologist Dr Tom Pering

Dr Tom Pering stands in front of Sakurajima volcano in Japan. Credit: Tom Pering/Volcano Blog.

Volcanologist Dr Tom Pering from the University of Sheffield’s Department of Geography recently took part in a reddit Science Ask Me Anything — an online Q&A session with one of the the internet’s largest and most active science communities.

Dr Pering’s research regularly finds him sitting on top of some of the world’s most active volcanoes as he monitors which type of gases they release. In particular, he is interested in volcanoes which have basaltic magmas. This type of magma allows the constant release of gases at the surface, which can then be measured using remote sensing techniques.

His research also looks at modelling of how gas behaves within magmas, which then leads to a range of volcanic activities such as strombolian eruptions, where pressure built up from entrapped gases causes lava to fling into the air in a series of small explosions.

Dr Pering is part of the University of Sheffield’s Volcano Remote Sensing research group which has been working on developing low-cost approaches to monitoring volcanoes, including an ultra-violet camera built with the Raspberry Pi platform.

Here are some of the best questions redditors had for him:

Q: Do gas emissions from a volcano tell you anything about its status? Will sensors like this work congruently with seismographs to better prepare for an eruption?

Yes! Here we need to consider the different behaviours at each individual volcano before we think about what gas emissions may tell us. We can broadly think of volcanoes as being “open vent” which constantly release gases from a central vent to the atmosphere, or “closed vent” which have a solidified vent and therefore don’t emit gases constantly or only at diminished levels.

The key to all of the studies of gas emissions following this is the understanding of what the normal level of gas emissions for a given volcano are. Any departure from these normal levels could tell us something about an individual volcanoes status. A change relative to this normal behaviour could then tell us whether an eruptive episode is ending (e.g., via a decrease in gas emissions) or whether we may have heightened unrest (e.g., via an increase in gas emissions), although these are not hard and fast rules as each volcano can behave differently (in terms of gas emissions) prior to a change in eruptive behaviour. In addition to this we also have to consider the type of gas released. There are three major constituent parts of volcanic gas: water vapour, carbon dioxide, and sulphur dioxide. Each of these gases are released from a magma at different depths below a volcano so a higher concentration of one gas compared to another can tell us a little bit about the depth of the magma that is present within the sub-surface plumbing system.

Monitoring seismic signals is another key method for monitoring volcanic activity, and they are already used quite extensively in tandem with gas emissions at certain locations worldwide, for example, Mt. Etna (Sicily, Italy) is a volcano I have done quite a bit of work on and the combination of seismic and gas monitoring has unlocked some really interesting things about the volcano. Our sensors, given their low-cost nature, could certainly open up gas monitoring more widely where it is not done as a matter of course currently.

Q: What’s it like to work at volcanoes? Are they lonely? Are there roaming teams of volcanologists around the base? Are there popular volcanoes to study?

Working on the flanks and at the summits of volcanoes is often an awe-inspiring experience. The volcanoes I travel to and work on are basaltic volcanoes which constantly emit gas and are often producing mild explosive eruptions while I am there (hence the awe-inspiring!). Depending on the volcano, accessing them can be quite hard physically, and whilst you are in and around the area, you always need to be thinking about safety. Hard hats and gas masks are almost always an essential.

Personally, I have never found a volcano lonely, this may be because we most often travel in research groups. There is a lot of comradery among these trips so they are nearly always great fun! Even when the group may split to perform tasks at different locations there is a sense of purpose, silence, and connection with the landscape that I can appreciate and find calming. The only time you get teams of roaming volcanologists around a base would be during a time of volcanic unrest at a specific volcano or during planned workshops where groups of volcanologists with like-minded interested convene to test and discuss methods.

Yes, there are more popular volcanoes to study (these of course depend on what you want to do and your core research interests). The most popular locations (in my experience) tend to be those locations which are easier to access and therefore require less money to get to, and also those with much more reliable activity, so you know that if you travel to that location you will more than likely be able to use your instruments to gather actual data!

Q: Great to see another use of the Raspberry Pi! How often is this type of low-cost technology used in the field now and what are the drawbacks compared to say the most expensive UV camera?

I know a lot of volcanoes are in remote parts of the world and this feels like a great opportunity to improve access for citizen scientists.

A: Low-cost technologies are now creeping in to science more widely across the board (i.e., not just in volcanology). In my view this is, at least in part, due to platforms such as the Raspberry Pi which are so flexible in their potential uses that they can easily be adapted to unique and individual scientific issues. At the moment, in the field of volcanology, we are just starting to see a more general interest in low-cost technologies in the field, such as our ultraviolet (UV) camera.

However, the main drawbacks of these are that you don’t get the “finished package” which would generally be provided by a more expensive commercial UV camera. We have spent the past 18–24 months developing our own UV camera (with full research and development costing less than an expensive commercial UV camera) to a stage that we are happy that it could be disseminated to others to enable more widespread use. So I guess here the major drawback is the development time needed.

You also touch on another key point here, citizen science. With cheaper technology and more widespread access to the internet and processing devices (smartphones are very powerful these days) the types and range of science that citizens can become involved with should broaden out. This is quite simply good news for scientists as some of the big questions of today just couldn’t be answered by scientist’s alone.

Dr Pering documents his trips up volcanoes on his Youtube channel.

Q: Are strombolis a popular food among volcanologists? If not, why not? What is a strombolian eruption and how can gas modeling tell you about them?

Unfortunately, I have never had a stromboli! After a quick Google these look tasty so now I wish I have had one…Probably haven’t had one because I wouldn’t know where to get one in the UK, and my cooking is notoriously average.

A strombolian eruption is a very short explosion which is associated with the release of hot and incandescent (glowing red/orange) material mostly a short distance from the eruptive vent.

A strombolian eruption is likely driven by a very large gas bubble, which we call gas slugs as they resemble the shape of bullet (they are also called Taylor bubbles). These bubbles can be almost as wide as the conduit (the conduit connects the magma chamber with the vent at the surface) and 10s of metres long. We can then model the behaviour of individual bubbles within a conduit under different conditions, for example: different magma properties such as density and viscosity, different conduit geometries, and different sizes of bubble. We can then try and match up our observations at a given volcano with our models to understand more about an individual volcanic system. A great example of a well studied volcano which exhibits strombolian activity is indeed Stromboli.

Q: Are you worried that increasing automation of these detectors will take you out of the field?

Not at the moment, but I do wonder where we will be with the standard of volcano monitoring in decades time. I think with the technology advances we are having in volcanology at the moment (and generally in science) there will continue to be research groups who seek to improve the performance of the current instruments we have and develop new ones which perform their functions better.

In short, there will always be a need to update and improve our available equipment. There is also a need to go out into the field and test, monitor, maintain, and replace existing equipment, or even expand beyond existing networks. In the future, we will be able to place many more scientific instruments of a wider variety around a volcano, so I think there will always be a need for fieldwork.

Enjoy reading this Q&A? You can follow Tom on Twitter or subscribe to his YouTube channel!

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