Please explain how the tides work.

[NandVsMom]

Originally Posted by nwcountrygal

Want to see big tides! Alaska!
http://www.youtube.com/watch?v=9d6pL3YSGTI
Bore Tide surfing! I can go into Anchorage for shopping go into town high tide come out miles and miles of sand. Whole tideal change in a couple of hours. This is not waves coming into the bay -it is just the changing of the tides.

That's more surge than our last tsunami! Incredible!

Does it go back out just as fast?

[NandVsMom]

Originally Posted by HankDfrmSD

Here's a good explanation, with a diagram of the continents that shows how tides move the water in the oceans:

Tides

What a fascinating link!

[nullgeo]

Originally Posted by NandVsMom

That's more surge than our last tsunami! Incredible!

Does it go back out just as fast?

Basically, the tides move in and out at a similar rate over time ... but what makes a tidal bore is the push of incoming, rising tide against the normal flow of a river ... so when the tide reverses and goes out, it then travels with the normal direction of the river, which means the water flows without disturbance.

[martyann]

Originally Posted by Lisa From Maui

I understand that, when I stand on a beach, for 24 hours strait, the tide will go up, then down, then up, then down. Has to do with the sun & the moon & how they pull water back and forth.


http://www.youtube.com/watch?v=l37of...eature=related


http://www.youtube.com/watch?v=Ead8d...eature=related


http://www.youtube.com/watch?v=kHvBUDk7kkQ&NR=1

I just got a tide calendar. It says, on any given day, tides hit different beaches at different times. I'll choose Friday June 10th, 2011 to make this easy. High tide hits Honolulu at 12 noon.

Shown below - same day, different beaches, different times.

High tide hits Haleiwa, O'ahu at 10:30 am.
High tide hits Kaneohe Bay, Oahu at 10:30 am.
High tide hits Hanauma Bay, O'ahu at 11:05 am.
High tide hits Honolulu at 12 noon.

High tide hits Kahului Bay, Maui at 10:15 am.
High tide hits Ma'alaea Bay, Maui at 11:45 am.

Why? Why the difference?

Because the moon orbits the earch, as well as the earth spinning on it's axis. When it is high tide in one place, it is low tide 90" on either side.