Light Water absorbs light quickly, especially wavelengths other than blue. Below 10 m, everything rapidly becomes blue. Below 600 m, ocean darker than a moonlit night Average ocean depth is about 4,000 m, so most of the ocean is very dark. Temp Ocean changes temperature much more slowly than land, but it has some unique characteristics. Surface water is warmed by sunlight.
Warm water floats on cold water.
Water moves horizontally and vertically. Horizontally, it moves mostly west at the equator until it runs into the continents. Circulates clockwise in N hemisphere, counterclockwise in southern. Also moves vertically in less obvious fashion. Cold water sinks off Greenland, circulates in a complex worldwide pattern.