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Download a zip file that includes all the web pages and downloadable files from the student materialsFor the Instructor
These student materials complement the Coastal Processes, Hazards and Society Instructor Materials. If you would like your students to have access to the student materials, we suggest you either point them at the Student Version which omits the framing pages with information designed for faculty (and this box). Or you can download these pages in several formats that you can include in your course website or local Learning Managment System. Learn more about using, modifying, and sharing InTeGrate teaching materials.Tides
People have been fascinated with tides throughout history, with various aboriginal legends dating back tens of thousands of years accounting for this phenomenon. One Native American legend tells of a Raven who wanted to alter the depth of the oceans to make it shallower and therefore make more food accessible for his people, while Australian Aborigines have legends that speak of the moon filling with water while it was waxing, and how water drained back out of the moon as it waned, demonstrating the understanding that the lunar cycle was associated with water levels of the ocean.
Our current understanding of the tides can be explained using Sir Isaac Newton's universal law of gravitation. He proved that the gravitational attraction between two bodies is directly proportional to mass, and inversely proportional to the square of the distance between them. This is the case with the relationship between the sun, the moon and the Earth. While the moon is relatively small, it is also relatively close to Earth and exerts a gravitational pull on the Earth's surface that is stronger than that of the sun, which is much larger but also much further away. It is this gravitational attraction of both the moon and the sun to the Earth that causes the periodic rising and falling of the ocean's surface that we call tides.
