Tides in the Bay of Fundy

The following activities will focus on tides and what causes them with a focus on the unusually high tides in the Bay of Fundy.

You may need to refresh your understanding of tides and what causes them.  Please open the site with the time lapse photography of tides in the Bay of Fundy and read the associated text.  Also view the two images located farther down the page.  You can enlarge the images by clicking on them.  To return to the original location just use the back button of the browser.
 

The sun, moon, and Earth exert a gravitational pull on each other.  The pull of the sun is much greater than that of the moon because of its enormous size.  However because the moon is much closer to the Earth, it actually exerts a greater gravitational pull on the Earth.

The gravitational pull of the moon draws the water toward it.  This causes the water to bulge.  This bulge is called high tide.  The moon also pulls the Earth towards it.  This then causes another bulge, another high tide, on the opposite side of the Earth. 

Question 1

Please view the animated image that shows the relationship of the Earth, moon, and sun on tides.  Pay special attention to where and when spring and neap tides occur.

Why do you think the Spring tides are higher than the neap tides?  Base your answer on the image you viewed.

After you have written your opinion/hypothesis use the following sites to investigate and determine whether or not you were correct.

http://www.sfgate.com/getoutside/1996/jun/tides.html

http://fox.nstn.ca/~freshair/tides.html

http://fox.nstn.ca/~carp/fundis2.html

http://www.the-sea.org/

If you were incorrect write down the correct answer.  State why you were incorrect.  REMEMBER!  Scientists often make hypotheses based on observations only to find out that they were incorrect.  This is common and much is learned from incorrect hypothes.

Question 2:

Return to the image showing the tides in time lapse photography.The article states that there are two high tides per day.  Actually each tide takes 12 hrs. and 25 min..  Two high tides occur in  24 hrs and 50 min.  This means that the high tide is fifty minutes later each successive day. 

EXAMPLE:   It is high tide at 4:00 pm.  The water will ebb until you have low tide and the next high tide will be at its maximum height 12 hrs and 25 minutes later.  The time would then be  4:25 am.  Once again the water will ebb to low tide.  The next high tide will once again be 12 hrs and 25 min later.  The time now will will be 4:50 pm. 
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