One More Way in which Global Warming Can Kill You
Melting the glaciers might trigger massive volcanic collapses, like the one that occurred during the 1980 eruption of Mt. St. Helens but with less warning and more panic. Or at least, that’s the sensationalized version of a paper in this week’s Journal of Volcanology and Geothermal Research. Lucia Capra looked at the dates of volcanic collapses during the last ~30,000 years and found that most of them occurred during periods of abrupt deglaciation.
Work done in Iceland has already shown a correlation between eruption volume and changing glacial cover. The kinds of volcanic collapse Capra talks about, though, are slightly different: rather than a simple outpouring of lava, these eruptions are initiated by a landslide. They start with a mountain that’s already been weakened by other developments in the volcano, and just need a little extra something – added ground water from climate change or glacial melt, for example – for the top to fall off and the whole mountain to blow. They’re much deadlier than Iceland’s nice effusive eruptions.
This note of doom only sounds for volcanoes that are currently covered by glaciers, of course. And the precise chronology of climate change, deglaciation, and volcanic collapse is still murky – the local paleohydrology of the volcanoes isn’t that well constrained, nor are the dates of many collapses. But still, if you felt like making another ridiculous global warming disaster flick, “melting ice caps set off explodey volcanoes explode explode fire boom” wouldn’t be a bad angle. Better than “it’s a hurricane AND a snowstorm AND a billion tsunamis!”, anyway.