Tuesday, August 26, 2008

Is a mega-Katrina "hypercane" possible?

The Daily Galaxy: MIT's Kerry Emanuel describes the worst nightmare hurricane that could ever happen -a "hypercane" with winds raging around its center at 500 miles an hour. Water vapor; sea spray and storm debris are spewed into the atmosphere, punching a hole in the stratosphere 20 miles above the Earth's surface; at landfall, its super-gale-force winds would flatten forests and toss boulders with a 60-foot tsunami-like storm surge flooding nearby shores. The water vapor and debris could remain suspended high in the atmosphere for years, disrupting the climate and the ozone layer.

Could this happen? Possibly. But this hypercane scenario is one of Emanuels' computer models. A professor at MIT's atmosphere, oceans and climate program, Emanuel studies the physics of hurricanes, deconstructing their behavior, and digs into their geological past -- all to understand what makes these monster storms tick.

No one knows for sure how hurricanes get started. The ingredients for cooking one up still remain a mystery. A basic recipe: ocean water 80 degrees or warmer, super humid air, and a bunch of storms with thunderheads. Some assembly still required: "Hurricanes are accidents of nature," Emanuel says. Hurricanes don't happen by themselves," he continues. "They literally need to be triggered."

To create such a monster storm, parts of the ocean would have to warm up to at least 100 degrees, and only the impact of a large asteroid hitting the tropical ocean or a massive undersea volcano could generate such intense heating. Emanuel and his colleagues theorize that asteroid-triggered hypercanes may have contributed to massive global extinctions millions of years ago…..

Katrina steps ashore, 2005. NASA, Wikimedia Commons

1 comment:

Anonymous said...

Fascinating post.