The Cascade range of volcanoes is pretty impressive to see from the ground. Stretching from California up to Washington, it includes famous mountains like Saint Helens, Hood, and Rainier. I’ve seen many of these while driving in the area, and they’re even cooler from an airplane.
But I have to say, the view from the International Space Station might be best.
[Click to cascadienate.]
This shot was taken from the ISS on September 20, 2012, and shows the region around Mount Shasta, a 4300 meter peak in northern California. It’s technically dormant – it erupted last in 1786. In geologically recent history it’s erupted every 600 years or so, but that’s not a precise schedule, so geologists keep an eye on it, as they do many of the peaks in the Cascades. As well they should.
To the west of the mountain (to the right in the picture, near the edge) is the much smaller Black Butte. I only point that out because you can see a highway winding around it to the right. That’s I5, a major north-south highway, and a few years back when my family lived in Northern California, I drove it on our way to and back from Oregon. Black Butte was a pretty impressive lava dome, looking exactly what you expect a volcano to look like. And looming in the distance was Shasta, but more standard mountainy looking. That appearance is, of course, quite deceiving.
I love volcanoes, and I’m fascinated by them. I’m hoping to visit some more very soon.. and I’ll have some news about that, I think, in the near future.
Image credit: NASA
Do you like volcano pictures from space too? Here’s a bunch of ‘em!
[Note: At the bottom of this post is a gallery of astonishing pictures of volcanoes taken from space.]
Note to self: visit Tahiti someday.
Why? Because this:
[Click to breathtakenate, and yeah, trust me here, do it.]
This image of Tahiti was taken by Landsat 7 back in 2001. We may think of Tahiti as a tropical paradise — because it is — but like so many other islands in French Polynesia it’s actually a volcano. In fact, its two: Tahiti Nui, the bigger one to the northwest, and Tahiti-Iti to the southeast. Both are shield volcanoes, built up from lava flows. Nui is older, with hardened lava flows ranging from 300,000 to 1.7 million years old, while Iti is somewhat younger, only a mere 300,000 – 900,000 years old. Both volcanoes have had events where the shield has collapsed, so there are no classic circular holes in their middles.
Not only that, but their appearance has been heavily modified over the millennia by rainfall and erosion. Those deep crevices are where water has flowed down and eaten away at the slopes, and the color is of course from vegetation that thrives there. All of this makes the pair less volcano-looking and more oh-my-god-I-want-to-visit-there-looking.
See that little triangular jut-out of land at the very top of Tahiti-Nui? That’s called point Venus, and is where Captain Cook landed to observe the 1769 transit of Venus (you should read that link; it’s a cool story). It took them nearly a year to sail from England to Tahiti. Not too many scientific expeditions these days take that long to reach their destinations… with the notable exception, of course, of planetary probes, which can take much longer than that to reach their own Point Venus.
I’ve been to three volcanoes in my life — Taburiente on the island of La Palma, Pululahua in Ecuador, and Crater Lake in Oregon (one of the most astonishing places I have ever been). They are magnificent, transcendent places, and one day, I think, I’ll find a way to visit this pair of craggy, warm, and fantastically beautiful volcanoes so far away.
NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Landsat data from the U.S. Geological Survey.
It’s been a while since I posted a cool image of a volcano from space! So here’s one that’s simply lovely: Puyehue Cordón Caulle in Chile, which has been continuously erupting for several months now:
This was taken by NASA Earth Observing-1 satellite on January 26, 2012. The ash has been falling for so long it’s covered the entire complex in a finely ground layer, coloring this area taupe (or ecru, or, as I like to call it, tan). You really should click to haphaestenate that picture; the full-sized shot is amazing. There’s so much to see, like the ash cloud streaming away from that vent, the detail in the big caldera… but my favorite part I think are the sharply-colored lakes in the region, which are such a contrast to the dull brown everywhere else (you can see one of those lakes in the bottom left corner of the picture above — look for the blue spot). For scale, the caldera’s bowl is about 2 km (1.2 miles) across.
Unfortunately, as pretty as this is, the implications are not so good: the forest in that area is suffering due to all that ash. Volcanic ash is not like some small-grained powder: under a microscope you can see it looks far more like ground glass, each grain festooned with dozens of sharp corners and edges. Breathing that stuff in is not good for your lungs. And, of course, it’s heavy — it’s rock, after all — so when it falls in large amounts it can do a lot of damage, especially if it rains.
Satellite imagery of active volcanoes is critically important: some small-minded politicians might mock it, but monitoring them saves lives. And, of course, there’s all the amazing science we learn as well.
I love these satellite views of volcanoes from space, and I’ve collected quite a few into a gallery slideshow. Click the thumbnail picture to get a bigger picture and more information, and scroll through the gallery using the left and right arrows.]
Over the course of several hundred years – most notably in the 17th and 18th centuries — winter temperatures in western Europe were much lower than normal. Glaciers came much farther south than they had before, and a famous painting shows people ice skating on the Thames river — which hasn’t been frozen since. The period is known as the Little Ice Age, and its cause has always been something of a mystery.
However, new research by scientists at the University of Colorado-Boulder (yay team!) may have pegged it: the LIA appears to have started abruptly in the late 13th century, between the years 1275 and 1300. Radiocarbon dating of plants from Baffin Island (north of the Hudson Bay in Canada) and sediment samples from a lake in Iceland indicate that there was a rapid onset of severe cooling at that time. It’s been thought that the cooling started around then, but it’s been hard to pin down until now.
More importantly, this narrows down the cause of the LIA: four tropical volcanoes erupted violently in that period. The ash would have darkened the atmosphere, letting slightly less sunlight down. Some of the gases emitted by volcanoes also cool the air. It seems clear these volcanoes are what triggered the Little Ice Age. But why did it last so long?
That may be due to what happened after the volcanoes erupted. Most likely, the warmer temperatures would have melted the north polar sea ice. This fresh water is less dense than salty water, so it would flow on top of the oceans, and wouldn’t have mixed well with the deeper water. This would have slowed the transport of heat from the equatorial waters back up north, cooling them further. That system is what maintained colder temperatures for so long. There were variations — the Ice Age was more of as series of pulses of temperature drops than one long period — but for centuries the heating of the Earth was disrupted in that region.
For a long time it’s been suspected that the Sun played a role here, too. During the period of 1645 to 1715 there were few or no sunspots, a time called the Maunder Minimum. Sunspots are dark, but they’re surrounded by a region, a rim, that emits strongly in the UV. These faculae, as they’re called, actually more than make up for the darker regions of the spots, so in reality sunspots add to the amount of light and heat the Earth receives, by a fraction of a percent. So an active Sun, it’s thought, may warm the Earth a teeny bit more.
The report lists 15 key findings about the changes at the Earth’s northern regions. Fifteen. Here are four that alarmed me particularly:
1) The past six years (2005–2010) have been the warmest period ever recorded in the Arctic. Higher surface air temperatures are driving changes in the cryosphere.
3) The extent and duration of snow cover and sea ice have decreased across the Arctic. Temperatures in the permafrost have risen by up to 2 °C. The southern limit of permafrost has moved northward in Russia and Canada.
7) The Arctic Ocean is projected to become nearly ice-free in summer within this century, likely within the next thirty to forty years.
12) Loss of ice and snow in the Arctic enhances climate warming by increasing absorption of the sun’s energy at the surface of the planet. It could also dramatically increase emissions of carbon dioxide and methane and change large-scale ocean currents. The combined outcome of these effects is not yet known.
That last sentence is — pardon the expression — chilling. The real truth of this is we don’t know how this will affect the planet. We know what’s happening (sea levels are rising as the Earth warms, for example), and we have a good idea why it’s happening (despite deniers’ claims), but we don’t know the long-term effects. All we can say for sure is, they won’t be fun.
And speaking of deniers, a claim I’ve heard bandied about is that a single volcano eruption pours more carbon dioxide into the air than humans do over the course of a year (the time scale may vary depending on the claimant, but as you’ll see it doesn’t matter).
[NOTE (added March 19): It occurs to me that some people might see the Moon rising today and think it looks HUGE because it's a "supermoon". However, it's far more likely they're falling victim to the famous Moon Illusion. You can read all about it here.]
If you believe the mainstream media, you might think this weekend’s "supermoon" will cause earthquakes, volcanoes, bad weather, halitosis, dust bunnies, and hangnails.
Guess what I think of this idea! Hint: check the name of my blog. Got it? Good.
In reality, this "supermoon" nonsense is, well, nonsense. I have some details below, but for those of you who are impatient (the tl;dr crowd) here are the bullet points:
OK, so, how about some details?
[This post is about the recent eruptions of Mt. Etna in Sicily. It's part of a set of gorgeous images of volcanoes as seen from space; the first three are of Etna. Click the thumbnail picture to get a bigger picture and more information, and scroll through the gallery using the left and right arrows.]
[This post about an erupting Russian volcano is part of a gallery of gorgeous images of volcanoes as seen from space. Click the thumbnail picture to get a bigger picture and more information, and scroll through the gallery using the left and right arrows.]
If I had to guess what planet this picture was from, I’d certainly think Mars. Wouldn’t you?
The color, the forbidding landscape, the volcanic cones seemingly untouched by time… it must be Mars right? Nope. It’s Earth.
This picture was taken by astronauts on the International Space Station back in March 2008. It shows a region of Saudi Arabia called Harrat Khaybar, an extensive lava field which is pretty recent. And I mean that geologically as well as in human terms; the eruptions may have started 5 million years ago, but some were only a couple of thousand years ago.
This area is incredibly dry today, but these types of cones form when lava mixes with water. So not too long ago this area must have been a lot wetter, but then something happened to dry it out. Now it’s volcanic rock, sand, and gravel as far as the eye can see…
… just like Mars. It goes to show you: the best way to understand the place you live is not only to study it, but to put it in context as well. Studying other worlds can only help us in figuring out how our own works.
Will I ever get tired of these satellite images of volcanoes?
No. No, I won’t.
That’s Krakatau, or Krakatoa, an active volcano in Indonesia (click the pic to pyroclastinate). If the name is familiar, then you may remember that this particular hill decided to throw something of a hissy fit in 1883. In fact in four separate monstrous explosions the volcano detonated with the energetic yield of about 200 megatons of TNT — several times the energy of the most powerful nuclear weapon ever tested. The explosions tore the island apart, and killed tens of thousands of people. It threw so much ash in the atmosphere that the global average temperature dropped over a degree.
As a solution to global warming it leaves something to be desired.
NASA, understandably, keeps an eye on Krakatau, and in this image by the Earth Observing-1 satellite you can see the ash plume blowing to the north (I rotated the image 90° to make it fit better here). The volcanic island you see here is new; it’s been building up since the 1883 event, and is roughly 2 km (1.2 miles) across. It’s hard to imagine that this beautiful and serene island was the epicenter of one of the most massive explosions in modern history, but there you go. But then, we don’t need to imagine it, when we have the science to hand us the data.
NASA Earth Observatory image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 team.