Fabian - dont misrepresent what I am saying; of course the gravitational effect is not different in your backyard. (I am assuming that you live on the same planet as the rest of us.)
Do you agree that tides in the Med are negligible?
Originally posted by wolfgang59 Fabian - dont misrepresent what I am saying; of course the gravitational effect is not different in your backyard. (I am assuming that you live on the same planet as the rest of us.)
Do you agree that tides in the Med are negligible?
Sorry, I was just trying to be funny.
Let's consider a swimming pool as large as the Med, then the effect would be roughly the same. I don't know much of the actual tides in the Meds, but I reckon you're right there. But it is certainly bigger effects there than in the Baltic Sea. Or in my normal sized swimming pool.
But in the Channel, the tides are bigger. Why? Because of the shape of the Channel. Waters is forced to be higher of reason that doesn't have to do with the gravitational pull from the Moon and the Sun. I think your expression 'slopping waters' is the key.
Originally posted by FabianFnas Sorry, I was just trying to be funny.
Let's consider a swimming pool as large as the Med, then the effect would be roughly the same. I don't know much of the actual tides in the Meds, but I reckon you're right there. But it is certainly bigger effects there than in the Baltic Sea. Or in my normal sized swimming pool.
But in the Channel, the tides ar ...[text shortened]... onal pull from the Moon and the Sun. I think your expression 'slopping waters' is the key.
That is just water forced into a small conduit so it naturally rises more than the overall seas. But I don't understand why the Med has not much in the way of tides. Wouldn't it just be a matter of the ratio of lengths of the atlantic v the med? The atlantic being say, 4000 Km across and the med 800 Km, whatever, then wouldn't it just be 4000/800 as the difference in levels? or its inverse.
Looking out from Dover and seeing the tide 'go out' most people think of it as going to France, ie the tide in 'Calais is coming in'. But as we know that is NOT the case. Low tide at Dover is high tide in ... (?)well potentially 90 degrees west or east of Dover.
So low tide in the South of France is low tide in Italy is low tide in Algeria etcetera. Where does the water go? Its trying to get to the mid Atlantic but cant - the Straits of Gibralter are too narrow. Hence negligible tides in Med. (But I believe fierce currents around Gibralter)
Thinking about British tides I guess another important factor is the continental shelf, if the surrounding seas were deeper the tides would be less (same volume of water moving but less area).
no-one has answred the original question yet,your all busy going on about how tides form. The sun does have an effect on tides (as does the moon) working with or against the moon but how do the effects of the sun form?
Originally posted by battery123 no-one has answred the original question yet,your all busy going on about how tides form. The sun does have an effect on tides (as does the moon) working with or against the moon but how do the effects of the sun form?
Originally posted by battery123 no-one has answred the original question yet,your all busy going on about how tides form. The sun does have an effect on tides (as does the moon) working with or against the moon but how do the effects of the sun form?
I think your question was well answered. What part is still not answered?
Is this the part not yet answered?: "how do the effects of the sun form?"
Then the answer is of cousre: Gravitationally.
Originally posted by FabianFnas I think your question was well answered. What part is still not answered?
Is this the part not yet answered?: "how do the effects of the sun form?"
Then the answer is of cousre: Gravitationally.
More exactly, it's the result of the gravity GRADIENT from side facing the sun to the side away from the sun and similarly, the gravity gradient of the moon on the moon facing side of the earth V the gradient on the side of the earth facing away from the moon. These two forces can compete or become additive, competing when the sun and moon are on opposite sides of the earth and additive when the sun and moon are on the same side of the earth. And all shades in between. So tides get much stronger and weaker twice a lunar month depending on where the moon is in relation to the sun and Earth.
The curious thing is that we get a spring tide (thats the big one) TWICE per lunar month; thats when the moon and sun are pulling together (obvious) but also (counter-intuitively) when they compete.
The neap tides are when the pull of the moon is at right-angles to that of the sun.
correct, the earth is orbiting at a constant rate, the centre at just the right speed to maintain a near circular orbit, however the side facing the sun is slightly closer and moving at the same speed so but with the gravity slightly stronger so the water on the surface would fall inwards on a more elliptical orbit if the earth had no gravity. But because of the gravity the water is held on the surface of the earth. on the other side of the earth the reverse happens.
12 Oct '07 20:00
Tidal Forces
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