Exploratour - The Surface of the Earth
Ocean Levels
Did you know that the oceans are not level? There are waves, of course, which make the surface of the water irregular at any given moment. But this is not what we mean when we say that the oceans are not level.
The Pacific Ocean is higher on the western edge near Japan and Australia, than on the eastern edge near the United States. This seems hard to imagine, but it is true. The high spots are shown in red in this picture. You might ask - then why don't the waters roll toward the east in a giant tidal wave? Usually, strong winds blowing across the equator toward the western edge help to prevent that from happening. Every once and a while the winds relent, however, and then warm waters do flow to the east, against the coast of the American continent. When this happens, the Americas experience El Nino .