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Patterns on loch's surface

Posted: Tue Feb 20, 2018 1:09 pm
by Grian
These sometimes direct and sometimes meandering paths and roads of smooth water through textured. What causes them? Sometimes they are so narrow but distinct and don't seem to relate to air flow and any obvious landforms. Hopefully visible in photo... Hopefully not the stupidest question ever!Image

Re: Patterns on loch's surface

Posted: Tue Feb 20, 2018 1:51 pm
by Jim
All sorts of things.
Depth differences affect the size of waves and even ripples over an area, they may also increase or decrease flow which again can affect the ripples and waves.
Presence of vegetation can also have an effect of stilling the surface locally, and I'm told fish shoaling can create a surface pattern too, but I can't claim to have ever identified such a phenomenon
There are currents and streams from tide, and from wind effects which push the surface around in different ways, and when 2 areas under different influences meet up you get a new pattern in between them. The surface water may continue to move for some time after the effectthat started it moving has stopped.
Some of the currents may be from fresh water sources (streams) extending further out to sea than is obvious and gradually mixing with the sea water.
Some sources may be warmer than the sea (power station returns, sewage outflows, even rain water runoff), or colder (rivers at some times of year) and that affects viscostiy and how the water reacts to other influences.
And of course there is pollution - a still area with brown fibrous matter is well worth avoiding in areas where the buildings may have septic tanks.

Sometimes you can read the patterns and find a calm patch to paddle in for while other times the patterns don't appear to relate to anything, it is all part of the mystery of the sea!

Re: Patterns on loch's surface

Posted: Tue Feb 20, 2018 2:06 pm
by Grian
other times the patterns don't appear to relate to anything, it is all part of the mystery of the sea!
Thanks Jim. Relieved it wasn't a simple answer.

Re: Patterns on loch's surface

Posted: Tue Feb 20, 2018 2:47 pm
by Stoney Mike
They can also be wakes from boats. Like vapour trails from planes in the sky, if the conditions are right, boat wakes can persist for a surprisingly long time as strips of flat water.

You might find the book 'how to read water' by Tristan Gooley an interesting read, covers this and loads of other stuff.

Re: Patterns on loch's surface

Posted: Tue Feb 20, 2018 4:47 pm
by Tom the Dane
Nessie!!!😎😉

Sorry, had to let it out!!

Sincerely

Tom the Dane

Re: Patterns on loch's surface

Posted: Tue Feb 20, 2018 8:46 pm
by Douglas Wilcox
Jim>
and I'm told fish shoaling can create a surface pattern too, but I can't claim to have ever identified such a phenomenon
Hi Jim back in the sixties the seas used to boil with shoals of mackerel quite commonly though nowadays it is rare. Last year we were traversing the Corryvreckan west to east at slack water. All of a sudden the water darkened round us then started rippling and vibrating. Murice had not been through the Corry before and nearly jumped out his boat as he thought the Hag herself was about to create a huge whirlpool round us.

Image
It was just a shoal of wee fish.

Of course tides do create some lovely patterns such as this one...
Image
...on the eddy line on the south edge of the Dorus Mor.

Dolphins also make some lovely patterns on the water....
Image

...then they go and spoil it all...
Image
...by coming up for air just when you were about to take a photo.

Douglas

Re: Patterns on loch's surface

Posted: Wed Feb 21, 2018 8:05 am
by Grian
I only once witnessed the sea boil with a shoal of fish and caught several mackerel with just a bare hook where the smaller fish were pushed close to shore. When the tide receded the seaweed round the bay was scattered with the silvery bodies of sprats.

I'll dig out the 'read the water' book, found it really interesting at first reading but must have skipped the relevant part.

Re: Patterns on loch's surface

Posted: Thu Feb 22, 2018 9:13 am
by seawolf856
So, do "still waters run deep" ??

Re: Patterns on loch's surface

Posted: Thu Feb 22, 2018 12:56 pm
by PeterG
Water arriving at the surface in a gentle upwelling doesn't have time to be affected by the wind so looks and is smoother, the sea is a 3 dimensional entity whereas we only work on two planes.

Re: Patterns on loch's surface

Posted: Thu Mar 08, 2018 3:47 pm
by 999birdie
This is a brilliant read if you're interested in this kind of thing - was bought it as a present, and have now read some other books by the author.

https://www.naturalnavigator.com/books- ... read-water

Re: Patterns on loch's surface

Posted: Fri Mar 09, 2018 12:00 pm
by Grian
999birdie wrote:
Thu Mar 08, 2018 3:47 pm
This is a brilliant read if you're interested in this kind of thing - was bought it as a present, and have now read some other books by the author.

https://www.naturalnavigator.com/books- ... read-water
That looks interesting, thanks.

Re: Patterns on loch's surface

Posted: Fri Mar 09, 2018 12:13 pm
by Chris Bolton
This is a brilliant read if you're interested in this kind of thing
I've ordered a copy.