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12 votes
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What visual wave behaviour help to tell if a tide is going in or out?

As SimonW points out strong tidal currents will modify the wave shape and significant height. The Wolf & Prandle (1999) study provides a neat summary description of the effects of currents (of ...
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11 votes
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Why 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 ...
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10 votes
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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 ...
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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 ...
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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 ...
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9 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 ...
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9 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 ...
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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 ...
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8 votes

Why 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 ...
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7 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 ...
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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-...
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6 votes
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What tidal databases are available to be used as model boundary conditions?

The boundaries to coastal models are frequently forced using information on water level (or, less commonly, velocities) predicted from databases of tidal constituents. These databases may be global or ...
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6 votes
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What are the effects of underwater "windmills"?

As you have noted, this technology is new, and so far only small numbers of experimental tidal energy converters (TECs) have been deployed. For this reason, little has been possible in the way of ...
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6 votes
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What is the area with the largest velocity vertical shear in the ocean?

Areas associated with velocity shear at a stratified interface are notably strong in the region of the Equatorial Undercurrent, straits (ex: strait of Gibraltar, the Bosphorus) and regions of the ...
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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 ...
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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 ...
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6 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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 $447.696$ $(10)^3$ $...
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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 ...
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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 ...
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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 ...
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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 ...
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