In navigation, what is 'fetch'?
Short answer
The unobstructed distance over water that the wind has been blowing, which determines wave size
Fetch is the continuous distance of open water over which the wind blows in a constant direction. Greater fetch allows waves to build to greater heights. In enclosed waters (short fetch) seas are typically smaller; in open ocean (long fetch) seas can become very large.
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In navigation, what is 'fetch'?