Coriolis effect at the equator?

So what happens at the equator? Does water just go straight down the drain?

Cecil’s Take

I was just watching Michael Palin’s travelogue Pole to Pole this past weekend, and when he was at the equator in Africa, there was someone who did a demonstration of this. According to the footage I watched, it did drain in one direction north of the equator, another direction south of it, and straight down right on the equator. He used matchsticks to demonstrate the direction of the water movement.

So I was all set to respond, but said shit, it’s GQ I should have a cite. I read your Wikipedia article. I also read Cecil’s, and both even take to task that it’s the Coriolis effect to begin with. So hells bells, I don’t know what I saw…

I saw a similar trick in Ecuador where the water went one way in the south and the other in the north, and straight down in the middle. The thing is, they only moved the tub a meter at most. I suspect a trick, as they were doing a bunch of other demonstrations that certainly were BS, like having a bunch of oldsters link arms while standing along the equator and saying they couldn’t pull apart for some reason. :dubious: This place is a few hundred meters away from the giant equator monument, which is certainly in the wrong place. The outfit had all the markings of a roadside tourist trap, and I doubt they have used anything more than a cheap GPS unit to find “their” equator.

As Cecil mentions above, the Coriolis effect has little, if any, effect on drains. There are far greater forces at work that determine which way water going down the drain rotates. Besides, I have drains that drain clockwise and counterclockwise in my house, and, last I checked, the equator doesn’t bisect my property.

I also saw the Palin episode about the Coriolis effect. Since I knew that weather patterns differ above and below the equator, and from what I was taught in school, I thought the demonstration looked feasible. Well, it ain’t!

There’s an explanation of what you saw here.

The trick can be demonstrated anywhere - no equator required.