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[Robert Kirk]

Dave...

It may have been a "soliton" a rare and not very well documented isolated 
travelling wave without the presence of a full wave field. Surface 
manifestation of a non-linear internal wave. They usually occur in narrow 
bays and straits - even along a canal towpath where they were first 
documented. They have been reproduced in wave tanks (USC 1976) and seen on 
satellite pix.
See this description:

    http://www.math.h.kyoto-u.ac.jp/~takasaki/soliton-lab/gallery/solitons/index-e.html

or this 
picture: 
http://www.lpi.usra.edu/publications/slidesets/oceans/oceanviews/slide_13.html

See, also the related "Tidal Bores" which are seen in narrow funneling bays 
with large tidal excursions.

Bob Kirk
Isobar #181



Dave Terrell wrote:
>Earlier this summer while I was sailing Grand Traverse Bay in winds of 2 
>to 4 kts apparent with calm flat water and no power boats in the area, 
>there suddenly appeared about about ten wave crests - one was a breaking 
>wave - I thiink some of them might have been two feet high. The water 
>around these waves was flat like all the rest of the water on the bay. 
>When they passed - having  bumped me around  pretty well - the sea 
>remained flat and the winds remained at the same speeds for most of the 
>rest of the afternoon. The wave crests went all the way across the bay. I 
>saw an other sail boat get knocked around as I was. The whole event lasted 
>about two minutes - maybe a little more or less.
>
>Any thoughts on what this event was? no reported midwest earthquakes or 
>tremors that I know of tha day. The waves did not resemble the wake of a 
>large power boat. To be sure I looked carefully and found none. Later a 
>large power boat passed by and its wake did not resemble what I 
>experienced in any way.
>
>really curious. I have never seen this sort of thing before.
>
>David, 432


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