Frequency of waves: How does it work?

Right Brain

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I've tried to find info about this since I heard about how waves strip sand or deposit sand, depending on the frequency. In other words, the speed at which they come into shore, e.g. if they're waves are coming in once every x seconds, this may strip sand from shore or deposit.

Another example is Summer vs Winter. Summer tends to deposit and winter strips.

There is also the factor of on shore/off shore winds and certain wind speeds, how do I put it together?

Does anyone know the finer details on this topic?
 
It's a complicated subject for sure. One thing to watch is wave height at high tide times....
Erosion seems to be tricky to predict, i've asked this same question a few times..
 
I've tried to find info about this since I heard about how waves strip sand or deposit sand, depending on the frequency. In other words, the speed at which they come into shore, e.g. if they're waves are coming in once every x seconds, this may strip sand from shore or deposit.

Another example is Summer vs Winter. Summer tends to deposit and winter strips.

There is also the factor of on shore/off shore winds and certain wind speeds, how do I put it together?

Does anyone know the finer details on this topic?

You are asking about the principles of physics, meteorology, geology, etc.

All cases include a specific point in time for a specific location.

To answer your question would be like telling the future.

So, I would say brush up on the principles, head out to start collecting data, and over time (perhaps decades) correlate your data for a specific area to formulate a hypothesis for a general assumption that may address your question.

This may help get you started: http://en.wikibooks.org/wiki/High_School_Earth_Science/Wave_Erosion_and_Deposition
http://www.mde.state.md.us/assets/document/wetlandswaterways/Shoreerosion.pdf
http://www.lre.usace.army.mil/coastalprocesses/CoastalProcesses/Erosion.aspx

That is a good question and if you are really interested pursue the answer, but understand it is one that could take a lifetime or two to answer.

Good luck!
 
I don't think there is any way to predict if sand will be eroded or deposited.You can make an educated guess after checking the weather forecast but it's still just a guess.There are too many variables; tide, wind speed and direction,wave frequency, speed, direction and energy,type of sand,coarse,fine or rocky, is the beach flat or sloped and on and on.The best way that I find is to learn your beaches and watch when it gets eroded and when it fills in with sand and try to remember all the variables that helped this happen so you can recognize when all these things happen again.And even then your still guessing but you will have a better chance of being right.I can't tell you how many times I have gone to the beach and the conditions are perfect, that night is perfect weather,no storm or wind and the very next day the beach is totally different or the beach is eroded and all the targets are gone,it sands in and I make great finds.Now even I am confused!!
 
Generally speaking, there seems to be more erosion when the waves hit the beach at a hard angle, as opposed to head on. It doesn't take huge waves to erode a beach, as we just learned from hurricane Irene. She actually brought more sand onto the beach.
 
Thanks for the links :) I've read some of those, very interesting.

Looked around the net on this topic, usually hard to find readable info.

I know there's a lot to talk about, but you gotta start somewhere. What if we lay the foundation and start with the downright facts and what other posters might know? Take it one step at a time.
 
Look up Beach Erosion and Deposition.

Generally during the summer there are less storms in the oceans, so the coasts don't get hit with many big swells (more on swells below), so the only waves the beaches are seeing are locally wind created waves, which are always small, unless you have a storm with high winds over your area. With these small waves, each wave deposits more sand than it takes away, and with thousands of waves a day, it adds up to a lot of sand deposited.

When the fall and winter come, the storms start brewing in the pacific/atlantic, and the high wind from those storms, creates waves in the water (swells), those swells travel outward like dropping a pebble in a pool, and travel until they hit something... it could be 6,000+ miles away. For example a few weeks ago the west coast was getting 10+ft waves, these swells were created by a big storm off of new zealand 6,500 miles southwest of us.

These bigger waves take away more sand than they deposit, especially at high tides, and also create big cuts in the sand... and with hundreds of them hitting in a day, it adds up to a lot of sand removed... and pulled into deeper water. These big waves take the sand that is all built up on the beaches during the summer, and spread it out into deeper water, creating a big sand bar in deeper water. Where as in summer, you have a smaller sand bar in shallower water.

Now onto swell, and your main question. When you look at a surf forecast for your area, there will be a swell forecast, it shows swell height, direction, and period, our average days around here are 10 second period, and 1 ft swell height, it equals about 2-3 foot waves. When those new zealand swells came in a few weeks ago, it was a 20 second period and 2 ft height... which created 10ft+ waves. Picture an audio wave form, and the difference between a bass note, and a high note, with the peaks and troughs, the time between each peak is the period, and the height that the peak is sticking above water, is the height, the longer the period, means that it is a big long wave form.

Check the surf forecast before you go hunting and note the swell height, direction, and period, and look at the actual wave size that it creates at the beach. Generally under 10 second period, is your average day, with smaller waves, but when you see a longer period getting to around 20 seconds, you may see some big waves that will take away a lot of sand.
 

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Generally speaking, there seems to be more erosion when the waves hit the beach at a hard angle, as opposed to head on. It doesn't take huge waves to erode a beach, as we just learned from hurricane Irene. She actually brought more sand onto the beach.

Oh yes, I remember reading about that. At my beaches, waves usually hit at about a 45 degree angle.
 
Got it!

I've tried to find info about this since I heard about how waves strip sand or deposit sand, depending on the frequency. In other words, the speed at which they come into shore, e.g. if they're waves are coming in once every x seconds, this may strip sand from shore or deposit.

Another example is Summer vs Winter. Summer tends to deposit and winter strips.

There is also the factor of on shore/off shore winds and certain wind speeds, how do I put it together?

Does anyone know the finer details on this topic?

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:lol:
 
I've done it all for you in my new book, "Terry's Tides & Treasures!"

For just $999.99, I tell you When to go; What to look for; Where to look; How to find it; and Why you can't do it without me!

You'll learn the secrets to Wave Frequencies, how and why they strip or deposit sand hiding your treasures, Plus, get my Exclusive predictions for Your beach!

I reveal the secrets of successfully calculating off shore wind speeds to pinpoint buried Rolex watches on the shoreline and - how on shore winds can effect gold and silver in the atmosphere.

Send your personal check or Money Order for $999.99 (+ $99.99 S&H) to:

Terry's Tides & Treasures!
Attn: Craig
457 Woodenthatbe Grate Road
Utopia Beach, NY 01812
:lol:

Oh man I just have to get your book. LOL:lol::lol: Very good, very good indeed:yes::lol:
 
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