Wind and Current Directions
Wind and current directions are based on opposite conventions. This can lead to confusion when looking up the direction of an ebb or flood in current tables. Even a "land lubber knows that "wind direction" tells you where the wind is coming from. Yet people often stumble on the concept that "current direction" tells you which way the ebb or flood is going (setting). So a "North wind" is coming from the north which means the air is blowing to the south, but a current that "sets North" means the water is flowing to the north. One thing that is consistent in all these directions, however, is that they are given in terms of "true directions" - not "magnetic directions".
I've never found an explanation for why wind and current directions have opposite conventions, but I suspect it may be rooted in the most basic and probably oldest methods to check these directions. Even today, one of the best ways to tell where the wind is coming from is by feeling it on your face. When a slight turn of your head in either direction causes an equal change in sensation on either cheek, you are facing upwind; to see which way the current is flowing, we look for logs etc. that are drifting. What we perceive is the downstream movement of the logs (not where they came from). - George Gronseth
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