dingbat
Supreme Mariner
- Joined
- Nov 20, 2001
- Messages
- 16,334
On that note, have you found that when looking at charts, (and you see the depth change) are there any guidelines to help anticipate conditions? For example, if I was moving from an area of 40 fathoms to one of 20 in depth, can I expect a certain rate of change in waves per change in depth? Does that make sense?
The rule of thumb is that the thickness of water affected is equivalent to half of the wavelength of a wind wave.
Using your 3 ft. x 2 second example, the wave would have a wavelength of less than 20 ft. This would make the wave less than 10 ft. deep. Moving from a deep of 40 fathoms (240 ft.) to 20 fathom (120 ft.) would have absolutely no effect on the waves.
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