Sunday, March 29, 2009

No Volcanic Winter for Us

I was fascinated by the footage of the volcanic eruption this month near Tonga. However, I was even more interested in the eruption of Mount Redoubt in Alaska (which was followed by several more eruptions, most recently yesterday). I started to wonder if either or both volcanoes could affect our weather, as has happened in the past.

A little bit of Internet research revealed that the Tonga eruption (with the plume's maximum height of 25,000 ft., or 7.6 km) was not sufficiently powerful to send particles into the stratosphere (10-50 km), where they can be disseminated around the globe and block the sun's rays. Mount Redoubt, on the other hand, sent ash 65,000 ft. high on Thursday, and it's not done spewing. My first assumption was that we could see a volcanic winter resulting from the Mount Redoubt ash in the stratosphere.

However, I learned that the location of the volcano matters as much as the height of the ash. The ash from arctic volcanoes stays in the northern hemisphere, where it tends to affect the weather mainly in south asia. If these models (based on the affects of Alaska's Mount Katmai and Novarupta eruptions in 1912) are accurate, then northern India should experience a much weaker monsoon than normal this year. That will be an enormous hardship in that dry, overpopulated country.

1 comment:

Anonymous said...

i've been wondering about this (and reading about "the year without a summer").
there have been several under reported volcanic eruptions in the last month or so that i just stumbled across.
i hope it's not bad news for anyone.