The tempests seem unremitting. Just as the awful news of Typhoon Haiyan’s devastation fades from the headlines, leaving millions destitute and desperate, tornadoes eviscerate Midwestern towns. In November. November??? The powerful tornado that struck Washington, Illinois is the only November EF-4 in Illinois history; there have been only 20 EF-4′s in recorded history in November for the United States (records began in 1950).
For climate –change deniers, these are unfortunate perturbations in the planet’s normal, chaotic cycle. For climate-change believers they are evidence of yet more horrendous events to come. For Kerry Emanual, a hurricane researcher at M.I.T., computer models predict that as climate warms, tropical cyclones will increase in number and intensity everywhere — except the western Pacific. Go figure.
But whether you are a climate denier, believer, or researcher, there is a new cause for concern. The Antarctic ice sheet may be doomed. Not from warming atmospheric temperatures above, but from volcanic heat below.
The Antarctic continent is infested with volcanoes. They include Mount Erebus (12,500 ft.) and Mount Siple (10, 200 ft.) which are active, and Mount Sidley (13,712 ft.). Stuck in the Earth’s freezer, the volcanoes are quiet and well-behaved. The chain, known as the Executive Range, may represent a mantle plume and possibly a rift zone that is slowly tearing East an West Antarctic apart. Its burbling, basaltic volcanoes are progressively younger from one end to the other.
Now, Doug Weins of Washington University has discovered the onset of new volcanic activity, just south of the youngest volcano, Waesche, and a half-mile beneath the surface of the Antarctic Ice Sheet. Weins expects this rising plume of hot basalt to erupt, though it’s unlikely to breach the surface of the ice.
The more imminent threat, when the 2000 F lava nears the surface, and likely erupts, is it that it will melt millions of tons of subsurface ice. And lubricate the bottom of an already warming ice sheet with millions of gallons of tepid water. The MacAveal Ice Stream is the likely recipient of this watery largess. And it is a major contributor to the Ross Ice Shelf—which has already demonstrated a suicidal talent for heaving vast chunks of itself into the Ross Sea.
The threat of rising seas that come with global warming is solemn enough. When coupled with storms it is hideous. But when geology gets into the act, it begins to seem like a planetary plot. Or maybe an urgent warning.
We still have time before this new and un-named volcano erupts beneath the Antarctic ice cap. The duration and volume are yet unknown. But it seems certain, climate change or not, that we are going to loose more ice, that sea levels will rise, and that , consequently, storms like Haiyon, or Sandy, or Katrina will be more devastating, regardless of their cause.
For the original paper: http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1992.html