01_Sthelens1

The most dangerous volcano of the world! Talk part I

Deep Space Live 26.9.2013 Ars Electronica Center by Birgit Hartinger The most dangerous volcanoes of the world, presented in the series  „In Touch with the Earth“ in the AEC. While preparing for this speech I came to notice that people, especially younger folks do not really know what a volcano is and even less what…

PoPo from view from San Nicolás

Popocatepetl

“Popocatépetl provides an excellent example of how the perception of risk is strongly influenced by the recent eruptive history and not by a full geological record, particularly among the people dwelling in the endangered areas and the media.” I think the above is probably a good quote that describes one of the biggest issues that…

Image Wikimedia Commons. Mount St. Helens erupted often between 1980 and 1986. An explosive eruption on March 19, 1982, sent pumice and ash 9 miles (14 kilometers) into the air, and resulted in a lahar (the dark deposit on the snow) flowing from the crater into the North Fork Toutle River valley. Part of the lahar entered Spirit Lake (lower left corner) but most of the flow went west down the Toutle River, eventually reaching the Cowlitz River, 50 miles (80 kilometers) downstream.

Volcanic Hazards: Lahars

Lahars are called jökulhlaups in Iceland, or mudflows in other regions of the world. What are they? A lahar is a combination of water with volcanic ash and lots of other debris. The necesarry water can come out of many sources: Glaciers are one source: IngeB wrote a really nice post on Icelandic glacier runs. When…