Volcano Story
A volcano along the Aleutian chain erupted, this one on Unmak Island. Unless there is loss of life, these kinds of stories pass quickly through the news cycle. But with friends in Anchorage and Homer, I always want to find out more.
This one was far enough away from either of those places to have much impact. And the residents of the island, apparently less than a dozen people, were plucked quickly from the island and moved to nearby Dutch Harbor.
A volcano blowing its top is another chance to learn a little geography, and my first choice to get beyond the news story, so to speak, is to do a little exploring on my own. My first destination is Google Earth, the software program that allows you to fly over the planet at any height and see geographical features three-dimensionally. I find it infinitely useful for many things: in this case, to get a closer look at the topography than I can get from the news story or photograph.
After reading the Associated Press story -- in my local hard-copy local newspaper by the way -- I fired up Google Earth and typed in "umnak island, ak." Actually, I misspelled it and the program asked me if I wanted the correct spelling. I clicked yes and soon was hovering over the island. Zooming to a lower altitude, I easily discerned a couple of volcanic peaks covered in snow at one end and a battered caldera at the other. By that time, I had the A.P. story in another window, and read that it was the Okmok Caldera that blew.
Google hasn't finished mapping the entire planet up close, though it updates the images as the satellite (it uses the Quickbird satellite owned by DigitalGlobe in nearby Longmont and is the same technology that gave us those clear images of Baghdad in the lead-up to the Iraq War). But the caldera has a newer image that allows me to fly right into it and hover just above the lake in the middle.
Remembering, of course, that the features I am seeing, high ridges and ash flows down one side, vegetation around the edges, are all now gone or altered forever in the blast, which apparently happened without warning soon after an earthquake hit the area.
A regular Google search gives me a page that says the caldera has erupted regularly in history since at least 1805, and the last one was in 1996. Most are ash emissions and some lava flows, which are easily visible in Google Earth from the top of the volcano to the ocean below.
I click on a purple dot near the caldera and it brings up a Wikipedia page that says the caldera is at the top of a shield volcano and that it once was filled with a lake 500 feet deep which eventually drained out through a notch on the northeast rim. The notch is easily visible, and if you zoom in close you can see rapids flowing down the flanks.
Another purple dot near the caldera brings up a WP page that describes Cape Field at Ft. Glenn, aka Umnak Airport, a WWII historical site for "for providing defensive cover for the U.S, bases in Unalaska Bay." It is also described as the most intact WWII base in the Aleutian chain that, at one time, housed more than 10,000 people.
The base is about 12 or 13 miles from the caldera. It will be interesting to find out in coming days whether the base is still intact or now covered in ash. I'll put an RSS search on some keywords and see what I can find out.