Loading...

Flashes of power

3,111 views

Loading...

Loading...

Loading...

Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Published on Apr 4, 2013

In the early 20th century, an American volcanologist named Frank Perret introduced a new term to the science of volcanoes, volcanology: "flashing arcs".

http://www.vesuvius.tomgidwitz.com/ht...

He described these as luminous flashes expanding radially from a violently exploding crater moving at enormous speed, too fast to be photographed. As we know now, these "flashing arcs" are compression (or shock) waves produced by very strong explosions, that travel through the air almost like a lightning. In recent years they have been filmed at a few volcanoes, including Eyjafjallajökull in Iceland in 2010

http://www.youtube.com/watch?v=zXBER2...

and Sakurajima (Japan) in 2011

http://www.youtube.com/watch?v=Gbrw2f...

Also at Etna, this phenomenon has been observed on a number of occasions, and I managed to film a few on 9 February 2012, at the end of one of those amazing episodes of lava fountaining also known as "paroxysms".

http://www.youtube.com/watch?v=h-bwBM...

The site of these paroxysms, since January 2011, has been a vent on the side of the youngest of Etna's four summit craters, the Southeast Crater. Initially this crater was a depression formed by collapse, a "pit crater", but during the latest and ongoing series of paroxysms, it has grown into a large cone, which is informally called "New Southeast Crater". In the past 6 weeks, this crater has produced nine paroxysmal episodes, the latest on 3 April 2013, and I had the opportunity to see, photograph, film, and HEAR this event, which was one of the loudest I have ever witnessed. (And I have seen - and heard - a great lot of eruptions on Etna in the past nearly 25 years.)

The sound level was still moderate when I recorded this video during the waxing phase of the 3 April 2013 paroxysm, and the audio is dominated by the gale-force wind blowing at my vantage point, an old cone on the upper southwest flank of Etna named Monte Vetore, about 6.4 km distant from the New Southeast Crater. The activity was characterized by frequent, and very powerful explosions from the crater itself (in the center-right part of the view), and low lava fountaining from a vent further west, in the "saddle" between the new cone and the old cone of the Southeast Crater, which is partially visible at left. The strongest explosions produced "flashing arcs" that can be seen travelling through the vapor plume of the old Southeast Crater cone at left - this short video shows no less than three of them, at 00:02, 00:55, and 01:09.

Loading...

When autoplay is enabled, a suggested video will automatically play next.

Up next


to add this to Watch Later

Add to

Loading playlists...