[Note: at the bottom of this post is a gallery of volcano pictures taken from space.]
Just in case you forgot that the Earth is one of the most geologically active worlds in the solar system*, the Icelandic volcano Grimsvötn has sent a very loud reminder: after seven years of relative inactivity, the volcano woke up on Saturday, rocketing a plume 11 kilometers (7 miles) into the air. The ash column blasted through the cloud layer, and was seen by weather satellites in space! Check out this amazing animation:
That was the view from the Meteosat-9, a European satellite in geostationary orbit. The animation is composed of visible light images and covers just under a three hour time span on May 21. You can clearly see the plume breaching the cloud layer and spreading out, then a second plume blowing through shortly thereafter. The shadow of the plume on the clouds gives an excellent but eerie sense of the scale of this event.
Here's a similar view from the US GOES 13 satellite showing 3.5 hours of the eruption:
Note the oblique angle and distance; GOES 13 orbits the Earth far west of the volcano. In the last frame of the animation you can see the outline of Iceland to give you an idea of the size of this event.
This volcano has erupted many times over the past few decades. I knew Iceland was active, but what really brought it home to me in this case was a quote by a company that operates the airport facilities in Iceland, when a 220 km no-fly zone around the volcano was established: it was described as "standard procedure around eruptions".
Yikes. The fact that they even need a "standard procedure" is eyebrow-raising to me; where I live, volcanoes are somewhat rare (maybe more so now than a millennia ago). However, this eruption doesn't currently look like it will be a big danger to air travel like last year's eruption of Eyjafjalajökull was; the ash is made of bigger particles which fall to the ground more quickly, and the volcano itself is located in a relatively isolated part of southeast Iceland.
Still, clearly, researching volcanoes and their eruptions is critical to many areas of life. Besides the knowledge added to our basic scientific understanding of geology and the Earth, monitoring and understanding volcanoes has a huge impact on air traffic, weather, and the daily lives of millions of people.
Image credits: CIMSS, UW-Madison (from images by EUMETSAT and NOAA). Tip o' the caldera to Jonatan Gislason.
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.]
* Jupiter's moon Io actually beats us in that category.