Sunrise over the Atlantic Ocean
Click on image for full size
Courtesy of UCAR and Carlye Calvin, photographer
Motions of the Ocean
Ocean water is always moving.
At the ocean surface, water is moved by the wind and Coriolis effect to form large surface ocean currents. These currents swirl water around ocean basins to create large loops of rotating ocean water called gyres. The Gulf Stream, a surface current that runs between the United States and Europe is part of a gyre in the North Atlantic. Often, smaller spinning rings of water called eddies form from surface ocean currents.
Ocean water is moving from deep to shallow areas of the ocean in areas of upwelling. This can have an impact on marine life and the regional climate. An upwelling area can create a cool, damp and foggy environment above the water. It can also drain power from hurricanes if they pass over. The upwelling water is rich in nutrients so plankton blooms are common.
The direction where surface water moves is affected by the direction of the wind and a process called Ekman Transport. Water at the ocean surface, moved by the wind, ends up moving at a right angle to the wind because of this process.
Moving water is found on a smaller scale too. Waves travel across the ocean and crash on coastlines. Currents along coastlines have the power to transport sand to new places and to even move swimmers far from their beach towels.
On a global scale, water moves each day with the tides. It also moves around the world from the shallow to deep oceans because of changes in the density of seawater - a process called thermohaline circulation.
The moving water in the oceans transports heat and so it has a large impact on Earth’s climate.
Shop Windows to the Universe Science Store!
The Summer 2010 issue of The Earth Scientist
, available in our online store
, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.
You might also be interested in:
The water at the ocean surface is moved primarily by winds. Large scale winds move in specific directions because they are affected by Earth’s spin and the Coriolis Effect. Because Earth spins constantly,...more
A gyre is another name for a swirling vortex. Ocean gyres are large swirling bodies of water that are often on the scale of a whole ocean basin or 1000’s of kilometers across (hundreds to thousands of...more
In areas of upwelling, deep ocean water makes its way to the surface. This has an impact on marine life as well as the region's climate. Upwelling happens commonly along coastlines. Winds blowing parallel...more
As a strong hurricane heads towards a vulnerable coast, people take precautions - boarding up houses, packing the car, and evacuating. These massive storms can spell disaster for people in hurricane prone...more
Ocean waves often approach a coastline at an angle. This moves water along the coast in a longshore current. Longshore currents grow stronger when the incoming waves are closer to perpendicular to the...more
The world has several oceans, the Pacific, the Atlantic, the Indian, the Arctic, and the Southern Ocean. While we have different names for them, they are not really separate. There are not walls between...more
The ocean and the atmosphere in the Southeast Pacific Ocean are connected in many ways. Strong trade winds blow northward along the west coast of South America. These winds stir up the ocean, bringing...more