Saturday, November 22, 2008

Taking a volcano's temperature

While running through my RSS feed, I came across this National Geographic article about using thermal infrared imaging to monitor and forecast volcanic eruptions. I'm currently working on a project that involves using satellite imagery to detect and map hydrothermal alteration products in a volcanic dome, so I was definitely interested, especially because the scientists involved are using data from the same instrument that I am.

First, I have to give them props for using the term "forecast" rather than "predict". I know a number of volcanologists who are touchy about using "predict", because any conclusions about what a volcano may or may not do are necessarily based on probabilities, just like a weather forecast. When people start thinking that we can say for certain when a volcano will erupt, we get the blame when it doesn't, and they have to deal with the consequences of precautionary evacuations - or if it erupts sooner and takes everyone by surprise. It's very important that people know that no scientist can be 100% sure when a volcano will erupt and what it will do - voclanoes are simply too complicated.

I also like the bit about volcanologists being "courageous scientists". I suppose that even though we're very aware of the danger involved in our work, we don't really see ourselves as courageous. It's just another aspect of a job, and for the most part a calculated risk when we venture onto an active volcano to observe eruptions. That said, if there are alternative ways to get the same information with less risk of getting injured or killed (or having to spend an inordinate amount of time and effort getting to hard-to-reach places), I'm all for them.

Anyway, the article discusses how Michael Ramsey and Adam Carter of the University of Pittsburgh are using a combination of ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) satellite images and FLIR (Forward-Looking Infrared Radiometer) camera pictures to monitor active volcanoes on the Kamchatka peninsula. This area of Russia is of major concern to both volcanologists and the aviation industry, because there a number of airplane flight routes go directly over this area. Erupting stratovolcanoes can create ash plumes that rise up to 50 km, far above the normal crusing altitute of a jet. The worldwide Volcanic Ash Advisory Centers already keeps a watch on these volcanoes using the MODIS (Moderate Resolution Imaging Spectroradiometer) and TOMS (Total Ozone Mapping Spectrometer). MODIS detects the thermal signatures of eruptions, and TOMS detects the gases - usually SO2 - associated with plumes.

(ASTER image of Bezymianny volcano lava flow from NASA Visible Earth image archive)


Ramsay and Carter (together with U.S. scientists at the University of Alaska-Fairbanks and Russian experts at Kamchatka's Institute of Volcanology and Seismology) worked at Bezymianny volcano, using the FLIR to record temperature increases in the lava dome just days prior to an eruption. They were able to correlate their ground data with data from NASA's ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) instrument, which records several bands of thermal infrared data. This is particularly significant because it means that for volcanoes with fairly well defined thermal precursors to explosive eruptions, scientists can use satellites to monitor them, rather than traveling to remote locations with expensive, cumbersome equipment.

There are a few caveats. Any thermal satellite image records not only the temperature at any one time in a location, but the temperature history. Thermal emissivity varies with the amount of energy a surface absorbs, and with the rate that the surface re-emits that energy. Some surfaces absorb lots of energy but lose it quickly; some absorb energy and emit it slowly; others don't absorb much at all. All of this shows up in a thermal image, which should be treated more as a time exposure than a single snapshot. The article sums it up pretty well:
"Because the satellite images capture an average temperature reading for the entire volcano at a given moment, the scientists knew the reading in some areas was probably many times higher."
This must be taken into account when analyzing satellite data. A single "bright" ASTER image can mean that temperature increased suddenly, or that temperatures increased steadily over the course of hours or even days, depending on how quickly the lava's surface loses heat. Several images, taken hours or days apart, however, would prove very useful. Unfortunately, obtaining even one line of ASTER data - or data from any satellite that records in the thermal band - is expensive, and requires a special requisition process. Additionally, most thermal data comes from instruments on satellites that also serve other purposes; finding a way to dedicate any satellite entirely to recording thermal imagery of volcanoes would be difficult and expensive (again). Still, it would be extremely useful - and it's exciting research even without that.

The research is being partially supported by the National Geographic Society's Committee for Research and Exploration. A Bulletin of Volcanology article about their work can be found here.

Friday, November 14, 2008

Volcanoes in fiction

Volcanoes are a really popular subject for movie-fiction - they're flashy, dangerous, unpredictable (unless you're Pierce Brosnan), and they explode. They're also appealing because moviemakers can, for the most part, get away with really spectacular CGI and not a lot of thought about the processes occurring on the volcano. (Not that they can get past us, but the average moviegoer hasn't had much volcano education beyond the cone-with-a-central-conduit diagram.)

Incorporating volcanoes into fiction, however, is riskier, because you can't just slap CGI onto the page. You have to describe what's happening, and if you have a crappy description, it makes the story less believable and generally lowers the quality of the whole reading experience.

I spend a lot of time reading fiction as well as non-fiction, and I'm always interested when I come across a story that tries to incorporate volcanoes. Here are a few that I've found so far:

Melting Stones by Tamora Pierce (an offshoot of the Circle of Magic series)
These books are meant for younger readers, but I've always found them entertaining - and very well written. This is the latest of the offshoots of a series about young "ambient" mages - people who draw their magical abilities from their environment. Evvy, the main character in Melting Stones, is a stone mage, and has to deal with a reawakening island volcano. The descriptions of eruption precursors - acidified water, sustained earthquakes, poisonous gases - are spot on, and it's really neat the way Tamora Pierce describes the forces at work within a volcano as if they were sentient beings. A good book if you like fantasy and realistic alternative worlds, and especially if you like strong female characters (a staple of Pierce's writing, and one of the reasons I enjoy her books so much).

Dark of the Sun by Chelsea Quinn Yarbro

The Saint-Germain vampire (yes, vampire) series by Chelsea Quinn Yarbro are fabulous and very well researched works of historical fiction. Yarbro gets to move her main character, who is a vampire (and thus immortal) through many periods in history, and in this book he lives through the 416 AD eruption of Krakatau. It's a fascinating book because you get to read how people might have reacted to a major eruption and its subsequent (very bad) climatic effects. Saint-Germain is forced to give up his merchant trade in China and move west; many of the people he encounters along the way think it's the end of the world, and rightly so, since their crops and animals die, diseases run rampant, and life just generally goes downhill fast. It's fortuitous for Saint-Germain because the ash in the atmosphere relieves some of the detrimental effects he suffers from exposure to sunlight - apparently volcanoes and vampires go very well together! The characters and writing can get a bit prosy sometimes, but the characters are complex and believable and you learn a lot about the cultures/time periods that they live in. (Right down to languages and clothing styles; really, Yarbro does so much preliminary research for these books that she could probably write a nonfiction companion text.)

Journey to the Center of the Earth by Jules Verne

The ultimate in geologic fiction. Volcanoes come into the story at both its beginning and its end; they are the route by which the travelers enter and exit Verne's subterranean world. I'm especially fond of the French version, since it's the original and nuances are often lost in translation (or obliterated entirely by clumsy adaptation). That said, the volcanoes in the story are not very realistic; even if they managed to get down into the crater of Snaeffels, Prof. Lidenbrock & Co would never have found an open volcanic conduit leading to empty caves and tunnels. For the most part, magma doesn't drain away after a volcano is done erupting - it sits there and solidifies and plugs up the plumbing. Likewise, the exit from Stromboli would not have happened - even providing a wooden raft had been able to withstand superheated water and magma pushing it up a volcanic conduit, one might expect that being blasted out of a volcano might prove problematic. Still, the book is great for depicting the science of geology as Verne knew it, and since no one really knew much about volcanoes at that point, it's interesting to see how he interpreted the facts available to him.


These are just a few things that I've found so far; I'm sure there are many others. What are your favorite works of fiction that include geology - accurate or not? (Book adaptations of movies don't count, and we've already excoriated those enough. Books that were turned into movies do count.)

Tuesday, November 11, 2008

Wild (and not so wild) animals in the field

I don't want to miss out on the domesticated or wild fun, so here are my contributions to the recent animal memes.

New and creepy insects are always turning up on field trips:




Fortunately, there are birds to take care of them - when they're not trying to steal your food.





Of course, why worry about birds when there are four-legged critters to watch out for?





Some are cute...



Some you wouldn't want to hug, but they could still qualify as cute...



Some definitely aren't cute or cuddly...


And some are are just so utterly comical that they require long breaks before any meaningful field work can get done.


video

Geology reference alert!

House is on, and our favorite misanthropic doctor just made a comment about mineralogy. And what's even better? One of the other doctors understood it.
[Yak yak yak how do we find this tumor if we can't bring the guy to the hospital and have only limited equipment...]
House: "What part of olivine, pyroxene and amphibole don't you understand?"
[Blank stares]
Cameron: "They're indicator minerals. You can't see diamonds so you look for the indicator minerals."
Woohoo! Geology metaphors strike again! (Although this one is kind of in reverse, but still, it's cool. I did a little happy dance when I heard it a few minutes ago.)

Thursday, November 6, 2008

This is SO right.

I just saw this and had to share. Oh, PhD, how relevant you are to my life...

Getting dirty

This week has been a fun one in my intro labs - we're doing a lab on rivers, and we get to play with the stream table. I've been pretty tired lately for various reasons, and I wasn't looking forward to teaching labs, but I am now, because this lab is just fun.

It's kind of amazing to watch a bunch of college students - most of whom are just taking the lab as a science requirement - get excited about something. It seemed like initially, they didn't quite believe they could learn anything by "playing in a sandbox", as one of the guys put it. But when I told them that the only thing I was going to do in the lab was turn the tap on and off, and made them get their hands wet and sandy and pruney, they started getting really interested. And when they reached the part in the lab where they got to design their own landscape and streamflow experiment, they were downright enthusiastic. Granted, the other TAs and I had a lot of fun testing out the table last week, but we thought that was just us being geology geeks. Turns out it wasn't just us. Some of the students wanted to stay late so they could do more experimenting.

And that, I think, is one of the best parts of geology, especially when you're just learning it. There's memorization, just like any other class, and you have to learn how science works, but you also get to go outside or to a lab and get messy and watch it work and There will always be people who complain about getting their favorite shoes dirty, or not wanting to touch the mucky fossil you just pulled out of a streambank, or not wanting to lick the halite to test that it's salty - but the ones who aren't bothered by it have fun. And that's great. There's no better draw than showing someone that geology is a science where you can do the same sort of things that you did as a little kid - playing around in the dirt and getting wet and scraping your knees up - and still learn something.

I'm looking forward to tomorrow afternoon, because the lab is mostly guys and I can definitely see potential for competition to build the coolest floodplain. I'll have to clean up the mess at the end, but it will definitely be worth it.

Wednesday, November 5, 2008

Whew

Now I feel better about life. (And yes, I'm breaking my "one election post" promise. It's worth it.)

I'm jazzed that this year, my vote did have a real effect - Virginia voted Democratic instead of Republican for the first time in forty years. At one point, the difference between the candidates was sixteen votes. SIXTEEN. That's just crazy, and it's especially crazy how long it took to call Virginia.

It's really wonderful when you actually have the feeling that you're an important part of a democracy, and what you think and do has an effect. It's a feeling I've only ever had when I was much younger and learning about how our government works, when everything was new and exciting. I'm so glad I was able to participate in a process like this, because so many people around the world can't.

I'm excited about the next few years now, instead of resigned, and the chance that I won't have to feel embarrassed by my country for a while makes me really happy.

I'm quite tired from staying up late, but glad I did; it's not often that I get to experience a positive turning point in this country's history. And, perhaps not most important overall, but the icing on the cake for me, I get to listen to a truly eloquent person make speeches at last. I can't describe how happy I am about that. The president is the face America shows the world, and I'm really proud that we've chosen to show them this one.


Now I'm going to go collapse on the lab couch for a few hours, because I am freaking tired. :)

Tuesday, November 4, 2008

Vote or die!

This will be my one and only almost one and only election post, because after spending 20+ years living just outside of Washington DC, talking too much about politics makes me twitch. (It's like the official recreational pursuit in the DC Metro area. We started, I swear, talking about this election about five seconds after the 2004 election was over. The official TV news graphics showed up a few days later).

Anyway, here's the meat of the post: GET OUT THERE AND VOTE.

Naturally, I won't tell you who to vote for - I have my own preferences and I suspect they're the same as those of most people who read science-related blogs. But I do want you to vote. I see too much apathy nowadays, especially among students, and this is one election where apathy is NOT an option.

I'm not sure how much of the election coverage I'll be able to stand watching tonight, unless it's the Daily Show, because all the other news channels have made me want to throw a brick at the TV at some point. (Too bad Dan Rather won't be around mixing metaphors until his head explodes - that was entertaining.) But I really, really hope I won't be disappointed tomorrow morning.

GO VOTE! I did...

(Yeah, I'm always a little sad about not getting the sticker since I vote absentee a lot. I'll just have to make do with this one.)

Sunday, November 2, 2008

Strumpeting

In the process of applying for extra funding for my graduate studies, I'm finding myself again stuck writing a "personal statement" essay, and I can't say that I'm fond of it. Oh, I have plenty of motivation to write the thing - what grad student doesn't want to, say, earn an NSF fellowship and not have to worry about their funding for the next three years? But I'm never comfortable writing an essay that basically demands that I trumpet how wonderful I am. (Dave Barry calls it "strumpeting", which he usually uses to describe what he does in a book tour, but it's basically the same thing.)

I don't mind writing about what I've done in terms of research, or my education, or my nonprofit work last year - that's basically just stating facts. But when it comes time to say, "I'm a wonderful scientist, and I can do better than everyone else I'm competing with, and my project will change the world"...well, I don't really like that. I'm not saying I won't do it - how else would I have gotten a job last year? - but it makes me really uncomfortable. It feels like hubris.

It's possible that this feeling stems from a need for more self-confidence. I'm constantly second-guessing myself on things, even when I'm reasonably sure that I'm right, and being able to write about myself in a confident way doesn't always come easily. I had a hard time with my grad school applications when it came to this, although judging by the responses I got, I must have been doing something right. I honestly don't know where this whole thing comes from, though. I never experienced any discouragement from my family or teachers when I let them know that I wanted to be a scientist - just the opposite, in fact. And when I got to college, I didn't come up against a single instance of anyone trying to discourage me because of my habits or gender or otherwise.

So I'm left wondering where I developed this minor phobia. I love to write, and I obviously love to write about what I do, or I wouldn't be blogging. But I don't like singing my own praises - maybe I feel that my work should be able to do that better than I can. At any rate, I'll sit here and write the damn essay, and it will be great, and hopefully it'll help earn me the fellowship. It's necessary, and it does get results, and as much as I complain about it, I'll still get the thing done. But I won't enjoy it.

(Then again, this could just be a "this is the weekend and I don't wanna work" sort of thing. But seeing as I've been putting off this part of the application for a while now, I'm betting it's more than that. Eh.)