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Topic: The Tides ... Take 5 (Read 3131 times) previous topic - next topic

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Re: The Tides ... Take 5
Reply #225
You are making things up again.  I clearly wrote what I am saying.
I read it years ago, and posted a link to it. I also noted he is wrong, which is ironic.
Quote from: Butikov
Observations do not agree with
this prediction. Instead, almost the opposite is usually observed: the moments of low tide occur approximately
at the culminations of the moon.
That's simply not true at all. That he doesn't know this, makes it hilarious.

Your claim is that tidal waves cannot exceed the speed of a free wave in the absence of tidal forces.  Butikov's mathematical results and computer simulations disagree.  Where is the mistake in his work?  What is he doing wrong?

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #226
Your claim is that tidal waves cannot exceed the speed of a free wave in the absence of tidal forces.
There you go again. Just making shit up.  If you would bother to check, and quote what was actually on the page, you wouldn't do this.
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • uncool
Re: The Tides ... Take 5
Reply #227
:ironicat:

Re: The Tides ... Take 5
Reply #228
There you go again. Just making shit up.  If you would bother to check, and quote what was actually on the page, you wouldn't do this.

You mean like this?

The dynamic theory explains the real world tides, and it is based on the real world physics, which clearly state friction prevents tides from travelling fast enough to follow the moon.  And this is based on ocean depth.  Nothing you say will change this.

And there is no physical way for a tide wave in a shallow canal to move fast enough to follow the moon.  Only if it is deep enough, in theory, can that happen.

 Butikov's mathematical results and computer simulations disagree with that.  Where is the mistake in his work?  What is he doing wrong?

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #229
Your claim is that tidal waves cannot exceed the speed of a free wave in the absence of tidal forces.
There you go again. Just making shit up.  If you would bother to check, and quote what was actually on the page, you wouldn't do this.
There you go again. Just making shit up.  If you would bother to check, and quote what was actually on the page, you wouldn't do this.

You mean like this?

The dynamic theory explains the real world tides, and it is based on the real world physics, which clearly state friction prevents tides from travelling fast enough to follow the moon.  And this is based on ocean depth.  Nothing you say will change this.

And there is no physical way for a tide wave in a shallow canal to move fast enough to follow the moon.  Only if it is deep enough, in theory, can that happen.
That wasn't hard was it?  You see how what you claimed wasn't the same as what I have been repeating?  (for almost 10 years now)
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #230
Here's yet another source that explains why tide waves can't go fast enough.

http://www.soest.hawaii.edu/oceanography/courses_html/OCN201/instructors/Carter/SP2016/tides_2016_handout.pdf

Bottom friction.  The thing Butikav leaves out of the equations.  It's why, as I have shown you in multiple sources, the forcing outruns the wave.  Which is a big part of why there are amphidromes, not two bulges.

"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #231
As for Butikov's papers, he is trying to explain the ideal tidal forces, not what actually occurs.
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • uncool
Re: The Tides ... Take 5
Reply #232
Your own source says forced waves can go with a speed corresponding to that of the force. Slide 13 (first slide on page 5). Bottom friction is something that affects the models after forcing is taken into account. And in the simplified model (either all-water Earth or canal Earth), the wave goes with the speed of the forcing.

  • uncool
Re: The Tides ... Take 5
Reply #233
On a side note, it does fail to take dynamics into account, instead presenting the two bulges as in the static version - it doesn't have the phase difference cold one has discussed.
  • Last Edit: June 11, 2018, 04:50:15 PM by uncool

Re: The Tides ... Take 5
Reply #234
As for Butikov's papers, he is trying to explain the ideal tidal forces, not what actually occurs.

He says he is solving the equations of the dynamic theory of tides.  But his conclusions directly contradict your assertions.  So what is his mistake, F X?

Re: The Tides ... Take 5
Reply #235
Bottom friction.  The thing Butikav leaves out of the equations. 

OK, that's at least a coherent statement.  Unfortunately for you, Butikov does not leave friction out.  Instead, he writes

Quote from: Butikov
If we ignore friction (dissipation of mechanical energy in the excited oscillation),
the forced motion occurs exactly in phase with the driving force, provided the driving
period T is longer than the natural period (T > T0). Otherwise (if T < T0) the forced
motion occurs in the opposite phase with respect to the driving force.

In equations (18) of http://butikov.faculty.ifmo.ru/TidesOD.pdf, you can see there is a parameter gamma - which would be zero if Butikov ignored friction.

Care to try again?


Re: The Tides ... Take 5
Reply #236
You know F X, if you were correct about the speed of tidal waves, it would mean that in the canal earth the number of high tides per day would depend entirely on the depth.  If the canal was pretty shallow, the wave speed would be small and the high tide line would move slowly.

As a numerical example, suppose the canal is 100 meters deep (uniformly).  Then the period of a free wave would be about 23 days - so someone living by the canal would observe one high tide every 11.5 days.  Change the depth, and you can get any period you want.  Getting two (or one) high tides a day would require the depth to be exactly tuned to the right number. 

This would also mean that the standard harmonic analysis of tides used on the real earth - which breaks tides down into harmonic constituents at discrete frequencies determined by the period of motion of the moon and sun - would fail completely, since the periods would be determined by ocean depth, not by astronomy.

Doesn't that bother you a little?  Feel some doubt creeping in?

Of course no such strange periods are observed anywhere on earth, including in shallow water near coasts, because tidal wave frequencies are not determined by the depth, but by the driving force(s).
  • Last Edit: June 12, 2018, 07:50:43 AM by cold one

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #237
You know F X, if you were correct about the speed of tidal waves,
There you go again.  You keep claiming it's "my view" of how physics and the world actually works.  Do you really think I came up with any of this?  (I did not of course) I have done nothing but use source after source to explain why I write things out about the tides.

Quote
In shallow water the tide and the tidal currents will be modified by the friction to which the waters are subjected when moving over the bottom. This bottom friction influences the currents to a considerable distance from the boundary surface, owing to the turbulent character of the flow (p. 480).
https://publishing.cdlib.org/ucpressebooks/view?docId=kt167nb66r&chunk.id=d3_6_ch14&toc.depth=1&toc.id=ch14&brand=eschol

Quote
On the equator where the planet's circumference is about 38,700 km (24,000 mi), the tide crest would travel at about 1600 km (1000 mi) per hr. On the real Earth, continents break up the ocean into separate basins and the ocean has a finite depth. Tides are shallow water waves so that wave celerity depends on water depth. For an average ocean depth of 4000 m (13,000 ft), the tidal celerity is about 200 in per sec (444 mi per hr).
http://oceanmotion.org/html/background/tides.htm

Quote
From this Earth-centric reference frame, in order
for the sea surface to "keep up" with
the forcing, the sea level bulges need
to move laterally through the ocean.
The signal propagates as a surface
gravity wave (influenced by rotation)
and the speed of that propagation is
limited by the shallow water wave
speed, C = gH , which at the
equator is only about half the speed
at which the forcing moves.
https://faculty.washington.edu/luanne/pages/ocean420/notes/tidedynamics.pdf

There is just so much wrong on the internet about tides.  Even an article about what is wrong about tides (Butikov mentioned the following ) has wrong shit in it, which is ironic.

Quote
You might think that with global positioning satellites we'd know the measurements of water and land tides accurate to a fraction of a smidgen. You'd be wrong.
https://www.lockhaven.edu/~dsimanek/scenario/tides.htm

Granted back in 2003 the esteemed Donald E. Simanek might not have known about the TOPEX data, but certainly in 2018 he could edit his page to reflect that we know a lot about the actual ocean tides now.

Even a hundred years ago actual research showed the depth of the ocean is what limits the speed of the tide, and shallow areas of the worlds oceans are where most of the tidal energy is lost to friction. Currently (as I showed in several links) there are calculations of how much energy is lost, and where it happens, which results in the changing of the earth's rotational speed, and the acceleration of the lunar orbit.  Because friction matters.  A lot.




"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #238
In your seemingly, magic world, because tides don't slow based on ocean depth, much of what we know happens due to the changes in ocean depth just couldn't happen.  I find that fascinating, that you still think that.
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • uncool
Re: The Tides ... Take 5
Reply #239
Whatever you say.

Re: The Tides ... Take 5
Reply #240
Quote
On the equator where the planet's circumference is about 38,700 km (24,000 mi), the tide crest would travel at about 1600 km (1000 mi) per hr. On the real Earth, continents break up the ocean into separate basins and the ocean has a finite depth. Tides are shallow water waves so that wave celerity depends on water depth. For an average ocean depth of 4000 m (13,000 ft), the tidal celerity is about 200 in per sec (444 mi per hr).
http://oceanmotion.org/html/background/tides.htm

That's a bit vague, but probably wrong.

Quote
Quote
From this Earth-centric reference frame, in order
for the sea surface to "keep up" with
the forcing, the sea level bulges need
to move laterally through the ocean.
The signal propagates as a surface
gravity wave (influenced by rotation)
and the speed of that propagation is
limited by the shallow water wave
speed, C = gH , which at the
equator is only about half the speed
at which the forcing moves.
https://faculty.washington.edu/luanne/pages/ocean420/notes/tidedynamics.pdf

That one is definitely wrong.  Well done!  I'll see if I can get that one corrected too, like the oceanography textbook.

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #241
Well done!
I posted all of those almost 10 years ago.  Which is why your idiot claim (that I quoted in the OP) is so damn funny.
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #242
Here. let me remind you.

that oceanography textbook you quoted while flailing around trying to support your FysiX? 
See how easy that is?  You posted something stupid and wrong, and I explain why you are an idiot.
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #243
that oceanography textbook you quoted while flailing around trying to support your FysiX? 
While I find it amusing (but ultimately boring) to watch you make shit up, I actually find your hard nosed math only approach to tides interesting. I posted this link many times, and it agrees with the Gravity book, which has also been posted multiple times.
Quote
Under these idealized conditions, we find that the moon's gravity attracts the surface of the ocean toward the moon. This creates a tidal bulge on the side of the Earth that faces the moon, like in the image below.

On the opposite side of the earth, another tidal bulge also is created. This is because the centripetal force of the rotation of the earth and moon "throws" water to this side of the Earth to balance the center of mass.

So what causes the other bulge? And since there isn't actually two bulges, why are there so many different sources explaining a non-existent two bulge situation?  And along with  all that, why are there different claims about the bulges?  Some claim they are ahead of the moon, others claim they are lagging behind the moon.  It's all so fucked up.  It really is.
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

Re: The Tides ... Take 5
Reply #244
So what causes the other bulge?

If you are actually asking, I'd be happy to explain it.

Quote
And since there isn't actually two bulges, why are there so many different sources explaining a non-existent two bulge situation? 

The right way to understand things is to start simple and gradually add complexity.

Quote
And along with  all that, why are there different claims about the bulges?  Some claim they are ahead of the moon, others claim they are lagging behind the moon.  It's all so fucked up.  It really is.

There are certainly a lot of wrong things on the internet.  The irony here is, by posting them because they support you, you're helping me correct them so they refute you...

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #245
  The irony here is, by posting them because they support you,
There you go again.  It's like you think I came up with the idea, then after the fact went looking for sources to support my idea.  Trust me, and you should know this by now, I ain't that smart. I got the idea from the sources.
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #246
"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

  • F X
  • The one and only
Re: The Tides ... Take 5
Reply #247
The right way to understand things is to start simple and gradually add complexity.
Stating something that is well known is a meaningless statement. 

Here's a simple start, which I used years ago, to explain why a tide can't move at 1000 mph.  (I usually say "because physics")



See?  That you think I came up with this is hilarious. 




"If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man."
― Mark Twain 🔭

Re: The Tides ... Take 5
Reply #248
The right way to understand things is to start simple and gradually add complexity.
Stating something that is well known is a meaningless statement. 

Here's a simple start, which I used years ago, to explain why a tide can't move at 1000 mph.  (I usually say "because physics")



See?  That you think I came up with this is hilarious.

You're such a fool.  There's really no other word for it. 

That book is an excellent source, and I agree completely with everything I read in it - which directly contradicts you.

(The page you reproduced is 111.  Did you read p112, by any chance?)

Re: The Tides ... Take 5
Reply #249
Quote from: Biology and the Mechanics of the Wave-Swept Environment
[so far] we have dealt with free waves...[that] travel under their own steam.  In contrast, tidal waves are forced...this requires the crest of a tidal wave to travel...every 12 hours and 25 minutes....a free wave would travel with celerity of 196 m/s and require 19 hours...Thus, the tractive forces must coerce the tidal wave to move faster than it otherwise would.
(my bold)

Now, F X, are you finally going to concede?  Or are you just going to hide from the burn for a few days and come back with more trolling?   The choice is yours....

  • Last Edit: June 14, 2018, 05:45:51 AM by cold one