Volcanoes are badass

Alaska's Mt. Redoubt, after months of seismic activity, finally erupted on Sunday. It erupted explosively 5 times in 6 hours. It sent plumes of ash 12 miles into the air. Ash is landing all over the state, forcing people to seal up their homes and cover up their cars, lest they become ash-breathing psycho mutants. It's not so great for air traffic either:

Mt. Redoubt has erupted several times before, most notably for five months in late 1989 through 1990, when its ash stopped the engines of a KLM jet in mid-flight. The plane dropped two miles before its crew could reactivate the engines.

Imagine being on that flight.

So, Redoubt is like the bane of the entire state of Alaska, and the rest of us might see some effects too. When volcanoes erupt explosively, they inject tons of aerosols (fine dust particles) into the atmosphere, and these are often light enough that they don't fall right away (some linger for as long as 3-4 years). With the help of air currents, these clouds are distributed around the globe.

This messes up the atmosphere pretty effectively: for one, the aerosols can scatter incoming solar energy and absorb terrestrial energy in a process called radiative forcing, which turns out to be the same phenomenon produced by the greenhouse gases we all know and love. For another, CFCs that we've poured into the atmosphere (but not so much any more, thanks Montreal Protocol) can start chemical reactions on the surfaces of the aerosols, speeding up ozone depletion (and getting us all a sweet tan).

One nice thing is that Redoubt's aerosols should make for pretty sunsets all around the northern hemisphere, since they scatter light pretty well. Go out and watch the sunset in the coming days, look for a characteristic purple color.

So, in sum, volcanoes are badass and they make pretty sunsets, but they're also kind of dicks.