Hydrosphere

Our global climate is also influenced by the way heat is transported by the Earth's oceans. Here you can see where the surface waters of Earth's oceans are warm and cold. Red and orange areas indicate the warmest surface waters, while green and blue are the coldest.

Things to notice:

• The north and south poles are colder than the equator, as expected.
• The pattern moves north and south with the seasons. During summer in the Northern Hemisphere the surface waters of the northern oceans are warm. At the same time it is winter in the Southern Hemisphere, and the southern oceans are cold.

An unusual rise in the temperature of the normally cool water of the Eastern Pacific is a phenomenon called El Niño, which means "The Child" in Spanish, since it occurs around Christmas some years. It can upset the global climate, causing droughts in some areas and flooding elsewhere. By monitoring global changes in sea surface temperature and circulation, scientists can now predict the onset of an El Niño.