12/30/2008 PERMALINK
Is a volcano big enough to cause an ice age really about to blow its top?
The most potentially destructive volcano on earth, the Yellowstone Caldera in Wyoming (see map), has recently begun experiencing an unusually strong and persistent earthquake swarm that has scientist concerned because it might indicate an impending eruption (see Today's Seismogram Display). Yellowstone is labeled a super volcano, because the pool of magma under the ground is a stunning 34 miles x 45 miles in size. Large enough that an eruption is expected to eject sufficient material to plunge the entire planet into a new ice age. The ridge shown in the photo is the rim of the huge caldera from the last eruption. Ash recovered from sediment over wide areas of North America shows that Yellowstone has had previous super volcanic eruptions 2.1 million, 1.3 million and 640,000 years ago.
The last time any super volcano erupted was 74,000 years ago, and recent advances in genetic archeology have shown that this eruption reduced the world's human population by over 90%, very nearly causing humanity's extinction. And Yellowstone's eruptions have been even bigger.
Vulcanologists aren't sure what to expect, since they have never observed a super volcano eruption, but they speculate that four warning signs are likely to precede the next eruption: 1. The ground rising due to magma building up beneath. 2. Increased geyser activity. 3. Earthquake swarms. 4. A release of volcanic gases.
Warning signs 1 & 2 have been going on for a number of years now, causing the Yellowstone caldera to be classified as a high threat for volcanic eruption by the U.S. Geological Survey back in 2005. USGS also warned that a Yellowstone eruption would produce "global consequences that are beyond human experience and impossible to anticipate fully."
Now the 3rd warning sign has arrived, but scientist disagree on exactly how much this increases the threat of an imminent eruption. What scientist can agree on is that Yellowstone remains an active super volcano certain to erupt again with catastrophic global consequences, and that our civilization has now entered the geological interval of maximum eruption risk ... more ... BBC/Discovery Channel docudrama of Yellowstone eruption (starts with a feint about a physics project, with Yellowstone eruption coming in at 1:22) ... watch ... History Channel documentary on Super volcano ... watch (Yellowstone eruption USA effects) ... watch (Yellowstone eruption global effects) ... See also: Humods Memes