I've heard quite a few times "The wind should kick in at the change in tide" or something to that effect and am having trouble figuring out how this could be so.

I can see how the inverse could be true, with the wind either accelerating or decelerating the speed of the tide coming in or out depending on whether it is blowing with the wind or against it.

But I can't see how the tide would change the wind speed. If it does, can someone please explain how without resorting to anecdotal evidence. ie. This one time the wind really kicked in when the tide changed....

Thats the exact theory. Basically at high tide the pressure gets squeezed a bit, especially if its cloudy apparently. Not sure how true this is though.

I reckon I should probably do some calculations, but it's POETS day today and I've already started drinking so I'll probably get them wrong.

GreenPats close

Its actually a "Vacuum" caused by volumetric change in sea level, not noticeable by human perception due to its vast expanse and has more effect coinciding with the Moons gravitational pull...

Of course other factors are involved too - but this is its origin.

Hopefully this answers your question as i have guessed and made some up too

whilst walking back up-wind for the umpteenth time, along the beach one day a few years ago, an old salty walking home in the opposite direction struck up a conversation with an introductory 'that looks fun'
'yeah' i said, 'but its heaps more fun when the winds stronger', to which the old salt replied, 'incoming tide always brings the sea breeze, she's on the move, give 'er an hour'.
i smiled, bid him good day and continued my way back up the beach.
the wind did pick up as the tide increased, and over the last few seasons i've paid attention as this has happened time and time again, even when its already blowin its tits off, it gets stronger when the time comes in. we quite often plan our indo island hops in relation to moon cycles to make the most of the swell and more often than not it pays off, and last kiting season we set our calendars to mid day and afternoon high tides to ensue we got the winds, now i know seabreezes hit during the afternoons mostly, but they were always stronger and got stronger last season on an incoming tide.

I would say the above therory is right, it's what i was also thinking.

I would have thought the atmosphere was subject to the same gravitational influence that the sea is. If the waters at high tide the air is too. So there must be some air movement due to this. I had always assumed it was trivial but maybe not.

jumpindave said...

ADEN said...

the simplest way to explain is:
kite when the tide is running opposite to the wind. you figure out the rest, it's not that hard.

Maybe in a river mouth set up, but the theory being disscussed here is that the wind comes in or increases with the incomming tide. so the tide is actually running with the wind in this situation.

but say the wind is blowing 15 knots and the tide is running with the wind at 5 knots, than you are only going to have the same power as if you were riding in 10 knots!!

stamp said...

^^ i've heard that too, the theory was something to do with the incoming tide bringing colder water in from out at sea, creating more temperature contrast with the land and increasing the strength of the seabreeze.
guess it depends on local tidal directions and strength as to how much and how cold the water is

Ahh, thermal differences, another quantifiable property for the equation. Anyone any good at thermodynamics?

stamp said...

^^ i've heard that too, the theory was something to do with the incoming tide bringing colder water in from out at sea, creating more temperature contrast with the land and increasing the strength of the seabreeze.
guess it depends on local tidal directions and strength as to how much and how cold the water is

That's it!

Bringing the cold ocean water closer into the shore, increases the air to water temperature difference, which as we know causes a seabreeze

I found this:

www.sailingworld.com/how-to/four-ways-to-win-sea-breeze-game/

3rd paragraph under "Pure sea breeze"

Great article, I think this answers the original question...

The tide brings in cooler ocean water which accelerates the seabreeze formation due to increasing the temperature difference between land and sea.

That works.... but seems to indicate that the tide only has an effect when a seabreeze is in play, ie the summer months....

andyy said...

Physics

and stuff

Clintos said...


That works.... but seems to indicate that the tide only has an effect when a seabreeze is in play, ie the summer months....

It should always have the same effect.
Although the tide would not be able to change the temperature difference enough to cause a seabreeze by itself, so yeah, it would only create a noticable increase when there already is a decent temperature difference caused by warmer air temp over the land.
It may slow down a land breeze slightly (not that we care!)

short answer[ not much]
except at a river mo

ADEN said...

the simplest way to explain is:
kite when the tide is running opposite to the wind. you figure out the rest, it's not that hard.

that is ok if you want to kite straight downwind and into the beach once because when you kite back out you are kiting with the tide therefore losing apparent wind. im tipping most people kite 90 degrees to wind, so how would your theory work? I think you meant to say that if the wind is blowing crosshore and tide is going out you would have more apparent wind coming in and less going out!