Spectators watch as an undersea volcano erupts off the coast of Tonga, tossing clouds of smoke, steam and ash thousands of feet into the sky above the South Pacific ocean, on March 18, 2009. The eruption was at sea about 6 miles from the southwest coast off the main island of Tongatapu, an area where up to 36 undersea volcanoes are clustered. (AP)
It’s volcano time in Alaska. Mount Redoubt, 100 miles southwest of Anchorage, blowing miles high over the land of grizzly bear and glacier.
And in the South Pacific — off the coast of Tonga — an undersea volcano erupting up through the waves in a spectacular display.
We don’t get to talk with volcanologists often here. Today we will — about the eruptions this week, the deep-Earth plumbing that makes them blow, and the consequences on the ground, the sea, and in the air, of all that power.
This hour, On Point: It’s volcano time. We’ll bring in the volcanologists.
You can join the conversation. Have you been following the reports from Redoubt? From north and south and South Pacific? What’s your experience of volcanoes? Your question on volcanoes?
-Tom Ashbrook
Guests:
Peter Cervelli joins us from the operations room of the Alaska Volcano Observatory in Anchorage. He’s the volcanologist and geophysicist on the job there.
From Girdwood, Alaska, we’re joined by Cyrus Read. He’s an engineer and geophysicist with the Alaska Volcano Observatory and travelled to the Mt. Redoubt observation hut this week. See images of the current Redoubt activity.
With us from Washington, DC, is Marianne Guffanti, senior geologist with the U.S. Geological Survey. She is the lead scientist for the USGS on the issue of volcanic hazards to aviation and serves as a technical advisor to the Federal Aviation Administration.
And from Pasadena, California, we’re joined by Mark Simons, professor of geophysics in the Seismological Laboratory at the California Institute of Technology (Caltech). He studies volcanoes worldwide using satellite imagery to detect bulges in the Earth’s crust as volcanoes become active.
Here’s a shot from the Redoubt webcam on Monday, March 23:
Alaska Volcano Observatory / U.S. Geological Survey
And here’s an amazing YouTube video of the eruption off the coast of Tonga in the South Pacific last week (more from YouTube here):
And here’s a video from the Discovery Channel highlighting their five favorite volcano webcams around the world…
Tags: geophysics, science, seismology, volcanoes
If I remember right, the whole North West United States is sitting on a volcanic timebomb. Magma is building up in a big well beneath the North West under places like Yellowstone ready to explode in the mother of all explosions. Is this true?
Posted by Noreen, on March 26th, 2009 at 10:25 AMSpeaking of subduction zones — would it be practical to make use of these as dumping places for radioactive waste?
Posted by Ed Cobb, on March 26th, 2009 at 10:29 AMWhat do your guests think about the idea of thermal drilling as a renewable source of energy? The idea of that much deep core drilling seems (to me) a very dangerous and bad idea. Or?
Posted by Jonathan, on March 26th, 2009 at 10:29 AMWhat would happen if all the world’s volcano’s erupted at the same time?
Posted by John Anthony, on March 26th, 2009 at 10:37 AMIf global warming melts the icecaps, wouldn’t there be a significant shift of ocean volume toward the earth’s equator? Would this redistribution of mass have an increase on earthquake frequency?
Posted by Frederick Burroughs, on March 26th, 2009 at 10:40 AMGreat show! I found it interesting that Mt. Pinotubo erupted during a typhoon. Are more relationships between surface processes and plate action coming to light? For instance, I heard that melting ice sheets can increase the elevation of the ground as the mass of ice decreases. Similarly, I wonder if the huge low pressure systems of a big storm could influence the weight of water on the plate to the point that it could induce an earthquake.
Posted by Gordon, on March 26th, 2009 at 10:43 AMLooking at these photos, what amounts of greenhouse gasses are being pumped into the atmosphere? How does an eruption like this compare to the use of SUVs and other human activity?
Posted by Matt, on March 26th, 2009 at 11:02 AMWhat does more damage to the ozone: a gallon of gas burned by a Hummer or, a gallon of gas burned by a leaf blower?
Posted by Frederic C., on March 26th, 2009 at 11:47 AMWhat process put more radioactive isotopes into the atmosphere:
one year’s output from a coal-burning power plant or,
Hiroshima, Nagasaki and Chernobyl?
Posted by Frederic C., on March 26th, 2009 at 11:52 AMI’m wondering what Bobby Jindal has to say about all of this?
Posted by Jean McBrien, on March 26th, 2009 at 12:18 PMHello: I’m with the US Coast Guard in Juneau, Alaska.
Among other things, we put out notices to mariners for the safety of shipping.
Just wanted to let you know that Mount Redoubt erupted during your show.
2009-03-26 09:42:14 – VAN/VONA
A large eruption of Redoubt volcano began at roughly 09:24 AKDT (17:24 UTC). National Weather Service reports the cloud height to be at least 65,000 ft above sea level.
You can get more information at AVO’s website.
http://www.avo.alaska.edu/activity/Redoubt.php
Posted by Dave Seris, on March 26th, 2009 at 1:01 PMMissed show this morning but listened later.
What are risks for volcanoes threatening the northwest, like Portland, OR, Seattle, WA, etc.:
Hood
Jefferson
Saint Helens
Baker
Adams
others?
Mt. Tabor in the city of Portland — is it really extinct?
Posted by howardr, on March 26th, 2009 at 5:48 PMYears ago the USGS published a great periodical called “Earthquakes and Volcanoes”. The funding must have stopped because the periodical vanished, but those people writing the articles must be still around publishing. Where can we find newer articles and is there any intent to restart the periodical?
Posted by Allan, on March 26th, 2009 at 9:38 PM