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14

I don't know about the size of land masses, but their distribution and the shape of ocean basins definitely play a big role. When considering the ideal case of an all-ocean globe, i.e. one with no land masses (equilibrium tidal theory), the combined effect of sun and moon give a theoretical tidal range of less than 1 m(1). As tidal ranges can be much larger ...


11

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 any kind) on waves: (i) Wave generation by wind—the effective wind is that relative to the surface current, and the wave age (cp/U*) and effective surface ...


9

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 the distance between the 3 systems and those motions cause interactions between the different frequencies involved. The Equilibrium Theory of Tides separates ...


9

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 cannot exist. Instead, the tides are dynamic responses to the tidal forcing functions from the Moon and the Sun, with the orbits of the three bodies about one ...


9

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 from a model that assimilates satellite data) for the global tides for a day in 2010 a week removed from the full moon. The page can be easily access on the day ...


9

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 so often - hourly is common. These use various methods, which have evolved over time, all aimed at having a very precise (sometimes down to millimetres) long-...


7

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 sea level height. There are about a thousand of these worldwide. In addition to these official tidal stations, there are even more private stations such as those ...


7

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-like coefficients. Tides at a locale are modeled as a sum of various frequency components, each with a magnitude and a phase offset from some reference. The ...


7

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 entire surface of Earth. Clearly that is not the case and in the diagram you can see the continents. Considering the different sizes of the basins and the distinct ...


6

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 of Tides into a set of harmonic terms. The list of relevant periods includes: the lunar day (period of lunar rotation), 24.84 mean solar hours. the sidereal ...


6

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 regional, and typically they offer a grid of points with constituents available at any of these points. The products listed below are all produced by global ...


6

(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 can be significant: Imagine a place that floods occasionally. Maybe just once a year, or less. Now think about how often it almost floods - where the water ...


5

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 harmonic calculations and from altimetry estimates using satellite observations (e.g., Topex/Poseidon). The input of energy into the coastal ocean is not uniform ...


5

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 measurement, and so as you note, all estimates are based on models or other means of prediction. To answer the second question first - how much the currents are ...


5

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 thermocline where internal waves are strong (South China Sea). These areas are typically associated with strong turbulence as a direct result of the strong ...


5

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 hundreds of really big ones, of more than about MM 7.0, so there is plenty of scope for a more rigorous study. They occur at all phases of the tides. Some have ...


5

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 constituents would be $M_2$ and $S_2$ (also the overtides and combination tides: $M_4$, $MS_4$...). The rest of the tidal constituents can be expressed as linear ...


5

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 sheltered behind low sandbanks/islands, which form the foremost coastline. Still the laguna is - obviously - connected to the open sea. Meaning: Huge waves, like in ...


5

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 partially caused by astronomical events. There's always some difference between predicted and observed tide levels. The former typically only use astronomical ...


5

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 be understood as follows Does that makes sense? The key is to consider the differences in gravitational pull felt by the Solid Earth and both the water ...


5

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 $447.696$ $(10)^3$ $kg$. Likewise, from your sources, the mass of the Moon ($m_{Moon}$ is $7.347$ $(10)^{22}$ $kg$. Typically a 747 would fly at an altitude ($r_{747}$) of around $...


4

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 very closely into the shapes of coastlines and bathymetry, the interaction between the inertia of the tidal wave and friction on the seabed, and so forth - a lot ...


4

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 correspond to various astronomical periods of the sun, the moon, and interactions between the two). There are some caveats to this. As David Hammen has noted, ...


4

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 pull more than the moon on the water it flies over for the short time it flies over it, that doesn't make a tide by any definition. At most a wave. But I think ...


3

Tidal constituents follow the expression: $\eta(t) = A cos (\omega t + \phi)$, where $\eta$ is the tidal elevation at a specific time, $A$ is the amplitude of the constituent, $\omega$ is the speed of the constituent (the rate of change in phase), and, finally $\phi$ is the phase of the constituent at the initial time from which the time is measured. The ...


3

For a general view of the surge in the region, the maps in u-surge give a pretty good idea of numbers and more affected regions. The USGS provides a comprehensive view of High Water Marks (HWM) in the entire region. If you are looking for observations, then the HWM database gives you the best spatial coverage. While HWM do not provide surge information per ...


3

The equilibrium tide is a theoretical concept developed by Newton in the 17th century that considers only the gravitational pull by the Moon and the Sun and the centrifugal forces, with no inertia, no friction and no land masses. From the NOAA definitions: equilibrium theory — A model under which it is assumed that the waters covering the face of the ...


3

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 important in that location, which I find very unlikely. In fact, the portal https://www.tide-forecast.com/locations/Fremantle-Australia/tides/latest shows the ...


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