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Why do high tides occur simultaneously on opposite sides of the Earth?

First of all, tides are not as simple as the "two-bulge" simplification. In reality, the diagram shown is misleading. The two bulges appear assuming an ocean of constant depth covers the ...
arkaia's user avatar
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10 votes
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How come the tide is low when the moon is high in the sky

This is based on the overly-simplified model of tides being the result of tidal bulges. As I explained in my answer to a related question on the physics.SE sister site, those tidal bulges do not and ...
David Hammen's user avatar
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The motion of tides

This question is quite interesting because it highlights some of the common misconceptions about tides. The animation from OSU shows their model results (not from a satellite as you mentioned, but ...
arkaia's user avatar
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10 votes

How will sea level rise be distributed across the globe?

There are many factors involved, so this is worth yet another answer. At the end of his/her answer aretxabaleta states: In general, the areas near the poles have a negative trend (sea level is ...
Jan Doggen's user avatar
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9 votes
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Why do high tides vary month to month?

The dynamics of the tides are quite complex. The main idea is that gravity from the Moon and the Sun affect water (and everything else) on Earth. The issue is that there are several motions that alter ...
arkaia's user avatar
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9 votes

Why do high tides occur simultaneously on opposite sides of the Earth?

Tides arise from the differences in gravitational pull across an object. That's why their strength falls as $r^3$ instead of $r^2$ (where $r$ is the distance between the two objects). Visually it can ...
Camilo Rada's user avatar
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8 votes

How is sea level measured?

There are two main approaches to measuring sea level (and thus its change): local and satellite-based. To measure local sea level we can set up gauges on the coast that record the water level every ...
Semidiurnal Simon's user avatar
8 votes
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How will sea level rise be distributed across the globe?

Sea level rise (SLR) is anything but spatially uniform. The satellite derived SLR rates that you present are a good example of the complexity of the spatial response. A good way to explore the ...
arkaia's user avatar
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7 votes

What goes into a tide power prediction for every fifteen minutes over the next twenty five years?

Tide prediction at some locale is more of an empirical art rather than an analytic science. It essentially is a reduction of decades or centuries of historical tide levels at the locale to Fourier-...
David Hammen's user avatar
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6 votes
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Definitions of tidal harmonic constituents...?

The explanation of all the tidal constituents is pretty complex because of the interactions between the different frequencies involved. The harmonic analysis is an expansion of the Equilibrium Theory ...
arkaia's user avatar
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6 votes

Is the Earth heated up by the tides?

A good estimate of the lunar tidal energy dissipated into the oceans is 2.5 Terawatts (Munk, 1997; Le Provost & Lyard, 1997). The value estimated comes mainly from two different sources: from ...
arkaia's user avatar
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6 votes

How is sea level measured?

How exactly to oceanographers measure sea level? By a number of mechanisms, some direct, others indirect. Various government agencies such as NOAA operate coastal tidal stations that measure local ...
David Hammen's user avatar
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6 votes

What has been the influence of the moon on Earth's temperature?

The complications of calculating the moon's contributions to earth's heat budget are touched on in Emergence of a Habitable Planet (2007) by Zahnle, et.al. in Space Science Reviews, a paper trying to ...
jeffronicus's user avatar
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5 votes

How was Venice flooded?

Venice can't really be flooded by rivers, since there are none worth mentioning throughout the city. High tides are predictable, yes. Take a look at how Venice is situated. The historic city is ...
Erik's user avatar
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5 votes

How is sea level measured?

(adding this as a separate answer as it's answering a different part of the question - one that wasn't there when I did my first answer...) To understand why a rise in sea level of as little as 10cm ...
Semidiurnal Simon's user avatar
5 votes

How will sea level rise be distributed across the globe?

The sea level will rise uniformly due to thermal expansion of the seas, but you are right that glaciers make things more complex. Basically when a massive glacier melts its gravitational pull is ...
Communisty's user avatar
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5 votes

Relationship between tides and earthquakes

I don't find Ide et al's recent paper to be very convincing. They only studied three earthquakes - hardly a statistically representative sample. There are millions of earthquakes on record, and ...
Gordon Stanger's user avatar
5 votes

What would be the impact on tides if the earth had no tilt?

A simple way to estimate the implications is to simplify the problem. If the orbits of Earth, Sun and Moon were circular and in the same plane, and the Earth had no tilt, the only remaining tidal ...
arkaia's user avatar
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5 votes
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How was Venice flooded?

If the winds subsided and the flooding was caused purely by tidal effects, which are astronomical events, shouldn't it have been predictable months, if not years in advance? The tides are only ...
David Hammen's user avatar
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5 votes

Do flights affect tides?

Both airborne planes and the Moon affect the tides, but the effect of airborne planes is so small as to be negligible. From your sources the mass of a Boeing 747 ($m_{747}$) is $447.696$ $(10)^3$ $...
Fred's user avatar
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5 votes
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What would be the effect of a geostationary moon?

First off, the geostationary Moon would have to be 115 times less massive as the actual one to match the gravitational pull. With that, one effect would be that the tidal pull would be stronger, but ...
Oscar Lanzi's user avatar
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4 votes
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Modelling sea levels with gravitational parameters

Starting from scratch and building a "toy model" is unlikely to be successful here, because while you could certainly model Newtonian tides, much of what happens on the continental shelves is tied ...
Semidiurnal Simon's user avatar
4 votes

What goes into a tide power prediction for every fifteen minutes over the next twenty five years?

As another answer has stated, tides can broadly be predicted far ahead by harmonic analysis (which is similar to taking a fourier transform of the tidal signal, but only allowing frequencies that ...
Semidiurnal Simon's user avatar
4 votes

Do flights affect tides?

A plane might be located 1.3*103 meters away from the surface of the ocean right underneath it, but for most of the ocean, it's located much further away, and at a very different angle. While it may ...
Erik A's user avatar
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4 votes

"Major Lunar Standstill" causing high tides?

Can a "Major Lunar Standstill" cause one-day high tides as described in the Jakarta article? Possibly "fake news", but very possibly yes. The possibly "fake news" part ...
David Hammen's user avatar
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4 votes

Effects of Dredging Estuary Channel on Water Flow

Although no information is given about the particular estuary that is the subject of this question, considering any estuary in a general manner can provide some conceptual views for clarification of ...
Thomas Perry's user avatar
4 votes

Why is the time interval between tides so irregular?

As David Hammen's answer illustrates, the dominant tide in different locations vary and the magnitude of each of the tidal constituents will change. The tide in the North Sea is relatively well ...
arkaia's user avatar
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3 votes
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What proportion of the energy input to the ocean tide system comes from the sun?

From [1, 2], the oceans are dissipating about 3.5 TW of energy. The moon and sun input about 3.2 TW and 0.5 TW, respectively. (0.2 TW of the 3.7 TW are dissipated by the solid Earth and the atmosphere....
John's user avatar
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3 votes

Can tides at night by consistently higher than in the daytime?

I find the statement in the question difficult to believe.Tides have a pretty cyclical period and I doubt the resulting effect is a day-night difference unless only S1 and S2 tidal constituents are ...
arkaia's user avatar
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