Ocean Currents & Their Effects on Oceans
Oceans exert a significant influence on the global environment through the constant movement of their waters. Some of the factors affecting ocean currents include climate temperatures, the Earth's rotation and water density. In turn, these huge bodies of water also exert their own influences and effects upon water current cycles.
Other People Are Reading
-
Ocean Currents
-
The oceans of the world---Arctic, Atlantic, Indian and Pacific---cover 71 percent of the Earth's surface and hold 97 percent of the Earth's total water content, according to the Minnesota State University of Mankato. Layers of warm water on top of cold alternate as current patterns generate a constant rhythm of movement. As cold waters move upwards, nutrient-rich materials from decomposed organisms provide needed food supplies for marine life, according to the Ocean Planet Smithsonian. As cold waters move upwards, warm waters move in to replace them at the deeper layers, where cooler temperatures cause warm waters to cool and become more dense.
Effects
-
The sun and the earth's rotations are the primary influences that drive ocean currents, according to the Water Encyclopedia resource site. The sun's influence can be see in its effects on the earth's atmosphere and the creation of winds. These winds move the water's surface areas. The sun also alters water density by making it lighter, or less heavy along the surface. The effects of the earth's rotation causes waters to move eastward in the Northern Hemisphere and westward in the Southern Hemisphere with the equator being the dividing line. This is known as the Coriolis Force and results from friction between the sea floor and the water.
-
Global Conveyor Belt
-
Circulation currents within deep ocean layers are influenced by temperature changes and changes in the water's density. These processes create a system of circulation called the global conveyor belt, according to the National Oceanic and Atmospheric Administration. As warm waters become cooled at the ocean's depths, they become heavier and start to sink. As cooled waters sink, warmer waters rise to the surface. These processes take on a global scale as the deep waters of the North Atlantic move southward, circle Antarctica, then move northward towards the Indian, Pacific and Atlantic oceans.
Salinity
-
In addition to the cooling effects on warm waters, salinity or saltiness also contributes to water density changes, according to the National Oceanic and Atmospheric Administration. The cooling effect causes evaporation to occur, leaving behind whatever salt content was contained inside evaporated waters. The combined effects from cooling and evaporation generate what's called thermohaline circulation patterns within ocean current movements. The increased salt content further adds to the weight or density of the water, which plays a part in the global conveyor belt pattern.
Circulation
-
As the global conveyor belt moves from warm regions to cold regions, the cooling and salinity effects work to perpetuate its movement around the globe, according to the National Oceanic and Atmospheric Administration. These deep ocean currents move slower than the wind-driven surface currents, with one patch of water taking as long as 1,000 years to travel the length of the belt. Through this system, the world's ecosystems are replenished as cool, nutrient-rich waters supply needed food materials for marine and plant life.
-
References
Resources
- Photo Credit ocean image by Deborah Durbin from Fotolia.com
