Alaskans Prepare For Volcanic Eruption 293
An anonymous reader writes "Mount Redoubt, or Redoubt Volcano, is an active stratovolcano in the largely volcanic Aleutian Range of Alaska. The once quiet volcano has begun to roar once again. Its last eruption was in 1989 and geologists suggest that the next one is upon us. Alaskans who lived through the earlier eruption are stocking up on breathing masks and goggles. Starting on Friday, January 23 2009, the level of seismic activity increased markedly, and on Sunday AVO raised the Aviation Color Code to ORANGE and the Volcano Alert Level to WATCH. On the basis of all available monitoring data AVO regards that an eruption similar to or smaller than the one that occurred in 1989-90 is the most probable outcome. We expect such an eruption to occur within days to weeks." From the AP article: "Alaska's volcanoes are not like Hawaii's. 'Most of them don't put out the red river of lava,' said the observatory's John Power. Instead, they typically explode and shoot ash 30,000 to 50,000 feet high — more than nine miles — into the jet stream. 'It's a very abrasive kind of rock fragment,' Power said. The particulate has jagged edges and has been used as an industrial abrasive. 'They use this to polish all kinds of metals,' he said." The server for the Alaska Volcano Observatory appears to be overloaded and is unresponsive.
I have a vague memory of St. Helens (Score:5, Informative)
I find this to be pretty exciting. I was just a little kid when St. Helens blew her top. I remember the ash coating our cars in Colorado. I thought it was so cool that it was snowing dirt.
Then again, I don't live right under the thing and my home, livelihood, health and property aren't currently being threatened by microscopic airborne razor blades.
Have any slashdot readers been close to an erupting volcano? Especially the subduction zone variety? Can you give us an account of what it's like?
These ring-o-fire volcanoes usually explode rather than ooze due to the composition of their magma. There's lots of dissolved gasses that like to become undissolved in massive bangs.
Re:I have a vague memory of St. Helens (Score:5, Informative)
Re:I have a vague memory of St. Helens (Score:4, Informative)
Then again, I don't live right under the thing and my home, livelihood, health and property aren't currently being threatened by microscopic airborne razor blades.
Those microscopic airborne razor blades will probably be distributed across much of the US due to the jet stream.
On the plus side, a dust mask is probably sufficient protection for those without beards.
Re:Let's work to avoid another "Katrina" (Score:5, Informative)
The entire state of Alaska has around 680,000 people.
So while this has the potential to be a major disaster, it will never be anything as bad as Katrina in scale and number of people affected.
Sitting here in Anchorage right now 'preparing' (Score:3, Informative)
Re:Let's work to avoid another "Katrina" (Score:0, Informative)
Based on all current reports, Alaaskan's are on top of it.
Re:Bah! (Score:5, Informative)
Ah, I'd forgotten about that one. Yeah that was pretty cheesy. They did actually manage such a feat [articlesextra.com] in Iceland once upon a time. Of course it took millions of gallons of water (far more then you'd get from fire trucks) and they didn't stop the lava flow -- all they did was divert it from a harbor that they were trying to save.
Re:Let's work to avoid another "Katrina" (Score:1, Informative)
The problem is that some of the most fertile ground you can find is right next to a volcano (usually, but not always). Not so important now, but it was hugely important during our agrarian days.
Re:I have a vague memory of St. Helens (Score:2, Informative)
Perhaps your hearing is limited in the low frequencies, or you haven't been in enough earthquakes, or you need to be in one away from buildings?
I have been in countless minor but very local earthquakes and some major ones, and have often noticed a deep rumbling or "roaring" sound before the first bit of obvious shaking arrives. The local ones were the loudest, sometimes consisting of a rumble and then one sharp bang which sounded like something crashed into my house.
Re:Damn globe (Score:3, Informative)
Re:Let's work to avoid another "Katrina" (Score:4, Informative)
In comparison, my impression is that most of the Anchorage metro area is at risk from a tsunami.
Negative. I've never seen it actually documented (or else I'd provide a link), but the urban legend (at least) in Anchorage is that Cook Inlet isn't conducive to tsunamis reaching the Anchorage area. Most of the water near Anchorage is pretty shallow, which you can verify for yourself by looking at Cook Inlet, Knik Arm and Turnagain Arm at low tide -- especially this time of year, when the glacial-fed rivers that empty into Knik and Turnagain arms are just barely trickling. Therefore, most of the energy of a tsunami would be dissipated before reaching Anchorage. Also, Anchorage sits on a ~100 foot high bluff. The airport elevation at Merrill Field is ~130 feet above sea level. While there are parts of Anchorage that are lower (the port and some of the area near the Coastal Trail), I suspect it would take a really large wall of water (which I already showed isn't likely) to flood most of Anchorage.
Re:And with all that ash in the air... (Score:3, Informative)