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Question about wave action on inland lake.
On Tue, 13 Apr 2004 22:57:34 GMT, wrote:
I have a boat on Lake Lanier in GA. The other morning I took it out,
and the overall wave action appeared to be different than usual.
It was a flat calm day, except when a passing boat produced some
waves. Most of the time the waves seem to be sort of peaked and
a bit sharp, but on this morning they were more rounded and flatter.
The first boat I noticed it from, I thought it might be simply due to
the shape of the boat itself. But after a while I noticed it was true of
all of them...which was cool with me because it meant I could go
faster without getting tossed in the air too much. It still made me
wonder *why* though. Could it have something to do with what
creates high and low tides, and/or why sometimes when you dig
a hole you seem to have more dirt than you took out and sometimes
you seem to have less? If so, is there a way to predict when waves
will tend to be sharper and when they will tend to be flatter, like
people can predict high and low tides?
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In general there seem to be two things that affect the shape of a
boats wake.
First is distance. The further you are from the boat that made the
wake, the less steep it wil become. Steep waves represent a lot of
energy, and the energy dissipates as the wave travels over a distance.
The other determinant is the type of boat and the speed it is
traveling. A fast boat traveling on plane will produce a steep
breaking wave directly behind the boat, with the height depending on
the weight of the boat and its hull shape. Large heavy boats that are
not yet on plane tend to produce a long gradual wake more like an
ocean swell.
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