Questions tagged [tides]

Tides are the periodic fall and rise of sea-level due to gravitational forces of the moon, sun or earth-rotation. When asking questions specifically about tides, use this tag and also include the [ocean], [moon], [sun] or [earth-rotation] tag if appropriate.

Filter by
Sorted by
Tagged with
0 votes
1 answer
62 views

Have we mined more on earth than 1% mass of moon? Because doing that to moon could potentially effect its gravitational pull

They say humans would need to mine 1% of moons mass to have an effect on earth's gravitational pull. Since the moon is 1.2% of the size of earth (tiny) & the minerals mined on the moon will be ...
0 votes
0 answers
22 views

How can a tidal height be lower than 'Chart Datum'/'LAT' e.g 'Lowest Astronomical Tide'?

We just had a very low low tide in the UK, an equinoctial tide on the 12th of March that was calculated as -0.13m above chart datum, i.e 13cm below the 'Lowest Astronomical Tide'. Check here for tidal ...
3 votes
2 answers
120 views

Do tidal forces affect subduction?

I know subduction in plate tectonics is mainly density driven. Probably a hypothetical question, but can weaknesses caused by tidal forces have an influence on the start of a subduction zone? Would ...
3 votes
0 answers
25 views

How to de-tide a daily averaged sea level data?

Coud you help me to resolve this situation? : I have a raw daily averaged sea level time series, as you know when we perform a harmonic analysis (e.g. using T_Tide from MATLAB) we need to put our data ...
5 votes
2 answers
99 views

Difference between two types of spring tides that occur every month

A spring tide is an unusually high tide that ooccurs when the sun, earth, and moon are colinear. I understand why this would be the case when the earth is on the far side of the sun and moon. The ...
2 votes
0 answers
30 views

were can I find the Greenwich equilibrium argument for tidal prediction(Vo+u)?

the closest i've got was with a table in the following manual that only went up to the year 2000. https://tidesandcurrents.noaa.gov/publications/SpecialPubNo98.pdf
1 vote
0 answers
67 views

Reason behind diurnal tides

I know that an area has a diurnal tidal cycle if it experiences one high and one low tide every lunar day. Many areas in the Gulf of Mexico experience these types of tides. I read that: Diurnal tides ...
2 votes
1 answer
235 views

How to construct the tide signal from harmonic constituents?

I am trying to reconstruct the astronomical tide time series from harmonic constituents (calculated from T_Tide).I am using the equation that all knows H(t) = Amplitude * cos ( t * harmonicSpeed + ...
14 votes
2 answers
24k views

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

Most explanations for high tides say high tides come from water being attracted by the moon (2/3) and the sun (1/3). Attraction occurring in the direction of the moon is visible on the side close to ...
3 votes
0 answers
119 views

How do I determine the phase lag for a tide

I want to determine the height of a sine wave for some tidal constituents for which I would use the following equation: 𝑌(𝑡)=𝐻cos⁡(𝜔𝑡−𝜙), where H is the amplitude, 𝜔 is the speed of rotation, t ...
3 votes
1 answer
65 views

Do the 600 satellites that orbit the Earth have any gravitational pull on the tides like the moon?

I know that space is big and satellites are small compared with the moon, but do they have, or will they if we get more, any effect on the sea and ocean water on the earth?
3 votes
1 answer
249 views

What would be the effect of a geostationary moon?

What kinds of differences from our Earth would we see with a moon in a geostationary orbit over the equator? Assuming the gravitational pull is roughly the same as it is with ours (my back of the ...
6 votes
2 answers
717 views

Why is the time interval between tides so irregular?

Looking at the tidal calendar for the German North Sea, I wonder why the interval between times is so irregular. Internet searches lead to pages that say the tides should be regular 24 hours 50 ...
2 votes
1 answer
82 views

What are good oceanographic journals

I am a developer with a oceanographic side project. I did some ML on wave & tide data and thought of publishing it in a paper. What are some good journals to send it to? Any recommendations? ...
2 votes
0 answers
28 views

Velocity boundary conditions from water depth time series

Currently, I am setting up a hydrodynamic model for a coastal zone. For this purpose I need to impose the velocity and water level at the open boundary. Tidal models (e.g. TPXO) can give both velocity ...
4 votes
1 answer
253 views

Effects of Dredging Estuary Channel on Water Flow

Is it possible to make some generalizations about the hydrographic effects of dredging a channel into an estuary? Or is it too complex a problem and each case must be considered independently? Let me ...
3 votes
2 answers
363 views

How large were Mars' ocean tides and to what extent could they keep the oceans mixing and tend to keep salinity uniform? Has this been modeled?

This answer to Salinity of Martian water 3.5 Billion years ago in Astronomy says that most estimates of Mars' ocean's salinity are pretty high; The article "Water Activity and the Challenge for ...
4 votes
1 answer
71 views

Why do ocean tides have negative and positive terms in their effects on Stoke's coefficients for calculating geopotential?

I have recently started working on calculating a Geopotential model based on GGM05C. In order to obtain a model as accurate as possible, some corrections must be applied to the normalized Stokes' ...
14 votes
3 answers
6k views

How will sea level rise be distributed across the globe?

Sea level rise from melting glaciers will not be uniformly distributed across the globe. However, it isn't clear to me what places will have the most and least extreme changes in sea level rise. I ...
5 votes
1 answer
228 views

Why is the tidal range at the entrance to the bay of fundy so high?

This question is a continuation of my previous question: Questions about the validity of a certain model for tidal resonance at the Bay of Fundy. I need to answer this question in order to return to ...
3 votes
0 answers
116 views

Questions about the validity of a certain model for tidal resonance at the Bay of Fundy

I'm currently working on a (relatively-simple) fluid-dynamics model of the tidal resonance at the Bay of Fundy, a place which is known for his world-breaking tidal range (15 meters on average, while ...
6 votes
1 answer
257 views

Calculating Love numbers (tidal deformation) for non-homogeneous planets

I have a question about planetology. I'm not sure if it belongs here, but the astronomy stack exchange seemed a bit odd, too. I would like to enhance my understanding of Love numbers. Love numbers ...
1 vote
1 answer
56 views

Would it be possible, from the earth’s creation or during its various geomorphological changes, for all the following hypotheses to be probable?

I’m designing a fictional world setting for a game, and I would like to know whether it has a relative coherence based on science. (Don’t mind if it is an almost improbable scenario). Would it be ...
3 votes
1 answer
670 views

"Major Lunar Standstill" causing high tides?

The Major Lunar Standstill, as the cycle is called, has been followed by serious starwatchers since the Babylonians. Like clockwork every 18.6 years, it triggers severe tide spikes, swells, and floods,...
5 votes
3 answers
533 views

Is it possible to predict the maximum daily/annual tide height without calculating hourly heights?

It's possible to predict tide at a given location and at a given time reasonably well (e.g. predicting low tide). And there are tools available that make it possible to do this calculation for any ...
12 votes
1 answer
405 views

What is the area with the largest velocity vertical shear in the ocean?

While there are areas with really strong tidal currents in the ocean, these currents tend to be primarily barotropic. My question relates to the largest vertical difference in velocity and it is ...
2 votes
2 answers
245 views

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

What proportion of Earth's internal heat is generated by tidal flexion as a result of the orbiting moon, and would it have been significantly greater four billion years ago when the moon was closer? ...
7 votes
1 answer
153 views

Tidal flow in an estuary

I am working on a project. Where this bacteria has been deposited at a port in the Humber Estuary. Where it has been deposited has been marked in red. I am trying to work out the limits of where this ...
6 votes
2 answers
4k views

Why do high tides vary month to month?

I've noticed that some ‘highest‘ high tides in one month are bigger than the highest high-tide of previous months. Why is this so?
1 vote
1 answer
513 views

What is the significance of amphidromic points related to tides?

On reading about tide formation and the role of moon's gravitational force, I came across the term amphidromic point. Could someone please elaborate this concept?
6 votes
3 answers
507 views

Do flights affect tides?

Can artificial satellite positions affect tides? on Space Exploration.SE asks if artificial satellites can affect tides, because they are a lot closer than our natural satellite, even though they are ...
2 votes
1 answer
239 views

How to correct PSMSL data for GIA?

I have a PSMSL RLR (revised local reference) sea level dataset with records from various tide gauges. Can anyone explain how to correct them for GIA (glacial isostatic adjustment) using the ICE-5G ...
5 votes
0 answers
38 views

Is it possible to know the tides of a particular location 50 years or 100 years from now?

Assuming no change in sea level (for the sake of argument), is it possible to know the high and low tides a half century or more in the future? Is information like this available to the general ...
8 votes
2 answers
129 views

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

I was watching a segment about tidal power generation on a PBS NewsHour broadcast. I've set the time code at about 11:45 to capture a little background. This bit ...
2 votes
2 answers
151 views

Modelling sea levels with gravitational parameters

Are there any publicly available programs or source code for modelling global (or local) changes in sea level which include parameters for gravitational tidal effects? I have a physics background, ...
1 vote
0 answers
56 views

Topography and flash flooding

I'm looking for a study or document showing the effect of the topography, slopes, the sea level and the tide on flash flooding occurrence. Thanks in advance
5 votes
1 answer
108 views

What proportion of the energy input to the ocean tide system comes from the sun?

The earth's ocean tides are primarily driven by the moon, but also by the sun. The relative strengths of the related tidal constituents varies from place to place across the globe. But what is the ...
3 votes
1 answer
133 views

Global tide calculation

I am familiar with the concept of harmonic tide coefficients and was wondering about the simplest software solution to calculate tides anywhere, worldwide. Are there any available, open source ...
9 votes
2 answers
292 views

How was Venice flooded?

If I understand this correctly, Venice was not flooded due to sudden rainfall causing rivers to overflow, but due to the high tides. These high tides were caused by an alignment of sun, which was ...
9 votes
3 answers
965 views

How is sea level measured?

In comments on Earth changes due to global climate change, sea level changes is a common topic. I hear quotes about sea level changes in the centimeter and even millimeter range and wonder how such ...
4 votes
0 answers
57 views

Simple numerical model of tide with an elliptic scheme

I have recently been given the task of developping a coastal model for tides. I have a few requirements, it must not be time stepping in order to be as fast as possible and in finite differences ...
0 votes
1 answer
1k views

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

Can the tides at night be consistently higher than in the daytime in southwest Australia in the port of Fremantle? Also, what is the explanation for the tides being significant during a part of the ...
4 votes
1 answer
2k views

How often do king tides (perigean spring tides) occur?

Recently, there has been a lot of information about "King Tides" (i.e, perigean spring tides) on the news with a number of groups relating the peak king tide to future normal conditions (2050) under ...
8 votes
1 answer
1k views

The motion of tides

I found this animation from a satellite: which shows the motion and elevation of tides on a certain date. Can you find an animation of a date when there is a spring tide? my question is as follows: ...
4 votes
0 answers
132 views

Presence of cross stratified conglomerates in fan deltas

Why are cross stratified conglomerates found in deposits of fan deltas? I know that fan deltas are alluvial fans that deposit directly into the sea, hence they are poorly sorted.But could not ...
3 votes
2 answers
2k views

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

I would like to know what would be the impacts/effects on the tides if earth were to have no tilt (perpendicular to plane of ecliptic)?
4 votes
1 answer
96 views

High tides at Venice

I read somewhere that the new MOSE system can withstand a maximum rise in water of about 3m. I was wondering if that extreme case will happen on the coast line of Lido di Venezia, there will be a ...
8 votes
1 answer
763 views

How come the tide is low when the moon is high in the sky

Happily spending my holidays in the Fiji Islands, I noticed a couple of days ago that when the moon was very high in the sky (my shadow was maybe 0.5-1m long) the tide was low. That really puzzled me....
5 votes
1 answer
175 views

If the distance between Earth and the moon were changed, would the effects be immediate? [closed]

I need your help on a possible (but perhaps low probability) scenario for how the distance between Earth and the moon could change: say a large object from the Kuiper Belt manages to make its way into ...
4 votes
2 answers
575 views

What was the storm surge height from Hurricane Harvey?

The numbers bandied about have been 3.6 m (12 feet) and even 4.6 m (15 feet), but something told me that was unlikely. As a guy who could "almost" slam dunk a basketball, the idea of a 3 m (10 feet) ...