NATS 1750 Lecture Notes - Lecture 12: Continental Crust, Oceanic Basin, Oceanic Crust
12 Apr 2016
School
Department
Course
Professor
Document Summary
The tides cause changes in elevation of the ocean surface. Caused by the gravitational forces exerted upon earth by the moon, and to a lesser extent by the sun. The suns position affects tides, but less than the moons effect. The monthly tidal cycle results in extra high tides called spring tide (occur when the earth, sun and moon align) during new and full moons. At this alignment gravitational forces added together so you get a large daily tidal range. During the extra low tides called neap tides the alignment is at the first and third quarters of the moon, so gravitational forces of sun and moon are offset. Daily tidal range (rise and fall) is least. Earth is often referred to as the blue planet. 71 percent of earth"s surface is represented by oceans and marginal seas. Continents and islands comprise the remaining 29 percent. Northern hemisphere is called the land hemisphere.
