Friday, March 17, 2006

Photo Quiz: What's Happening in this Photo?

How come this boat is cruising along nicely even though there is no wind?


Tillerman said...

They must be sailing on a lake. Any lake sailor knows that the wind at the surface of the lake can be totally different from the wind a few feet higher and different again from the wind at the top of the sail. You can fool yourself by looking at the ripples on the water thinking that gives you a clue where the wind is - but the clues are often wrong. It's quite possible to have totally flat water but enough wind higher up to fill the sails and drive the boat.

Either that or
a) photoshop
b) hyperdrive
c) how sails work is even more mysterious than some of the folk commenting at my blog think
d) carol anne from five o'clock somewhere has put a spell on the boat.

Litoralis said...

Why must it be a lake?
Why is the wind different at different heights?

I think the answer to the second of these questions is part of the answer to Tillerman's "How Sails Work" posts.

Tillerman said...

Wind is a 4-dimensional phenomenon; most sailors have 2-dimensional brains.

Carol Anne said...

If you look at the terrain in the background, you will see that the boat is sailing not only on a lake, but on a desert lake, where winds are even more bizarre than ordinary lakes.

Winds on desert lakes are influenced by the air flowing from canyons and around mesas, and it is certainly possible for a tall boat such as that one to have very different wind conditions at the top of the mast than are at the surface.

Some of these wind conditions are so well known as to get names, such as the famous "Elephant Fart" that occurs at the tail end of the butte for which Elephant Butte Lake was named.

Or you can take Tillerman's choice d) and give me all the credit.

EVK4 said...

4th mode?

Litoralis said...

Here's a clue: The lake is the Great Salt Lake.

Here's another: Boundary layer.

kamagra said...

How come this boat is cruising along nicely even though there is no wind? I think that the answer of this question is that the work that do the people who work in the boat is so important!