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sea smoke vortices
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| [Note Guidelines] Photographer's Note |
| This three frame composite shows four vortices in sea smoke over the Atlantic Ocean. These look like mini-tornadoes, but are more like an extreme cold version of dust devils over water. All were shot at -20 to -25°C before sunrise. They are not connected with water or clouds (see L frame), so are very different than waterspouts or tornadoes. They appear to be a conduit for the warmer less dense surface air to flow up through the cold dense layer above, much like a dust devil. They are more common than I thought at first, but are still not routine and can be very difficult to photograph. I now have several dozen images recorded including a 2 min life cycle composite and one decent short mpg. It takes a long lens (35 mm equivalent focal length of 380 mm used here), vigilance, luck, and planning. Most important is a tolerance for getting up before dawn on the coldest mornings of the winter and being outside for an hour or two. These vortices have a structure and life cycle like a tornado (see R frame), but usually last 2-3 minutes at most. After sunrise the solar heating disturbs the stable inversion that seems to be critical for their formation, so you won't see them if you get up late (at least according to my 4 years of experience since seeing my first one). Contrast and lighting are major problems shooting them, so some enhancement like the color inversion in the R frame can help show the structure (see the tornado like spray zone). Scale varies widely, but some seem to be in the 50-100 m range in height. The left frame has a partly obscured navigation buoy between the two vortices and the middle frame shows some birds (cormorants?) flying by, so you can get a sense of size. If anyone else has photos of these vortices, please contact me. Likewise links to the same. There is one such shot on TrekNature, but virtually nothing elsewhere on the web. |
Dave, bobair has marked this note useful
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- Dave
![Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 517 W: 47 N: 663]](http://i1.treknature.com/misc/g-s-g.gif)
(2127) - [2007-11-13 14:29]
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Hi Bob,
You wrote an excellent note regarding this phenomenon which is always appreciated.
While obviously not being in the "beautiful nature photography" category your shots are very appropriate for learning about nature. By the note it looks like it took a fair amount of dedication to capture these shots.
Well done!
I hope to see more of your work although time constraints have not allowed me to spend as much time as I'd like here on TN.
Welcome to TrekNature!
![Silver Note Writer [C: 2 W: 0 N: 42]](http://i1.treknature.com/misc/n-n-s.gif){kind=small}