In the Company of Volcanoes

- Dr. Janine Krippner Today marks another anniversary of the deadly eruption of Mount St. Helens volcano in Washington, USA. This eruption was one of those events where most remember where they were around the world when they heard the news. It changed the lives of those around the volcano - those who lost friends or family, their homes, their view of the local landscape, and their belief that 'it won't happen to me'. Fifty-seven people were lost, including volcanologist David Johnston ( his biography is out now here ). People around the world know this volcano after this day. Mount St. Helens on May 18, 1980. Courtesy of USGS. Thirty-nine years ago the world watched as the eruption took place, so what did they see? What it was like for those who experienced the eruption firsthand? What did the rest of the country see through the experiences of reporters and those who were there? When the next continental-US volcano erupts some of us will be there. Some of us wil...

- Dr. Janine Krippner We are fortunate that there is a large availability of volcanic eruption videos online for all of us to enjoy (see below warning), and we can learn a lot from them too. When I am looking at my satellite images of dome collapse block and ash flow and column collapse pyroclastic flow deposits on Shiveluch and Mount St. Helens volcanoes I have videos of these processes running through my mind. This is a short guide to what you are seeing in these incredible videos. WARNING: There are very dangerous and life threatening hazards associated with retrieving this footage, and here at In the Company of Volcanoes we strongly discourage anyone from trying to take your own. It is never, ever worth risking your life. --- This video shows the dome at Unzen volcano undergoing a partial collapse in 1991. This shows how a near-solid body of rock rapidly fragments down to smaller pieces of rock and ash, creating a billowing ash plume rising from the block and ash...

-Alison Most of my research can be described as looking at rocks to figure out what happened in the past.  There are many deposits from volcanic eruptions that don't just contain rocks. As volcanic soils are very fertile, many volcanoes are forested which means that falling ash or debris flows interact with trees and other plants. The way trees are damaged by the eruption can tell us a lot about what happened. The trees in the blast zone of Mount St. Helens are a dramatic example. Trees blown down by the 1980 later blast at Mt St Helens (image from 2015). I was recently lucky enough to visit Calbuco Volcano in the lake region of Chile. You may remember the impressive pictures of Calbuco erupting at sunset on April 22, 2015.  This heavily forested stratovolcano produced a large plume (which dropped tephra, coarse scoria on the slopes of the volcano and ash all over eastern Chile and Argentina), pyroclastic flows, and lahars (debris flows) from melting gla...

- Janine and Alison This morning I (Janine) was researching the May 18, 1980 Mount Saint Helens eruption to begin the next phase of my research. Reading through the descriptions of the start of the eruption - when massive blocks of the volcano slid to the north, I enthusiastically jumped out of my chair surprising my office mates. Marking out 1 meter with my feet I looked up at them and told them "this is one meter, now imagine 50 of these. Now imagine a massive chunk of rock moving 50 of these in one second! 50 m per second! This is nuts!" The joys of sharing an office with an over-enthusiastic volcanologist... 50 m/s is how fast the side of the mountain began to travel down and away from the volcano, taking chunks of rock the size of 30 story buildings northward. As the slide evolved into a debris avalanche, the sediment mass began flowing, the blocks reached speeds of up to 80 m/s [1]. So this got us talking about the insane speeds involved in volc...

- Janine Cotopaxi volcano is Ecuador's most intensively monitored volcano. With an active past, glacier-covered summit, and surrounding population it is watched very closely by the local team of volcanologists at IGEPN . Monitoring network on and around Cotopaxi volcano that has been growing since the first seismic station installation in 1976. Courtesy of IGEPN. Cotopaxi started quietly rumbling to life again in April with an increase in seismic activity. A Seismic swarm on 14th of August preceded phreatic (water) explosions on the 15th, and now Cotopaxi is on Yellow Alert in a phase of near-continuous ash emission (for more details see the Smithsonian Reports ). The above video was posted on August 18th and shows white steam/gas plume emission and ash fall on the snowy flanks. The above video shows ash emission on the 21st of August with the ash plume that did not exceed 2 km on this day. Ashfall affected the south to west, west, and northwest of the vol...