June 26th, 2008

Coriolis Corollary

I received a bit of brilliant information from my brilliant cousin John Paul, who did his PhD research on Chaos Theory and its applications in the El Nino weather phenomenon. Not knowing much about Coriolis and his crazy effect, I am happy to reprint this for all of you:

That bit about, "toilets and sinks swirling in the opposite direction," in the Southern Hemisphere? It's actually a myth.

Take it from your cousin with the PhD in climate physics. ;) The Coriolis Effect only has an effect on motion at the scale of say, oh, Rhode Island. Or in other words: the water (or wind) would have to move several miles before the Coriolis Effect deflected it more than a foot or two.

Which means you really do need a toilet bowl the size of Rhode Island for the Coriolis Effect to make it spin, "in the opposite direction," one side of the equator vs. the other.

Water down a toilet or a sink spins whichever way the shape of the bowl and the direction of the water causes it to.

So, the Coriolis Effect really only causes hurricanes and weather systems (but not tornadoes; they're too small) to spin the other way 'round in the Southern Hemisphere. More interesting: The Coriolis Effect drops to zero as you near the Equator (and, I think, the poles).

So THANKS John Paul, I miss you alot, and you're super cool.