The Oceans Perpetual Motion
The ocean is not a placid body of water. It is a swirling convoluted mess of current flows due to temperature differentials and winds. The swirling flows of Earth's perpetually changing ocean come to life in a new NASA scientific visualization that captures the movement of tens of thousands of ocean currents. The high-definition visualization is available in 3-minute and 20-minute versions at: http://svs.gsfc.nasa.gov/goto?3827 .
An ocean current is a continuous, directed movement of ocean water generated by the forces acting upon this mean flow, such as breaking waves, wind, Coriolis effect, temperature and salinity differences and tides caused by the gravitational pull of the Moon and the Sun. Depth contours, shoreline configurations and interaction with other currents influence a current's direction and strength.
Developed by NASA's Goddard Space Flight Center in Greenbelt, Md., the visualization is based on a synthesis of a numerical model with observational data. The model was created under a NASA project called Estimating the Circulation and Climate of the Ocean, or ECCO. A joint project between NASA's Jet Propulsion Laboratory, Pasadena, Calif., and the Massachusetts Institute of Technology, Cambridge, ECCO uses advanced mathematical tools to combine satellite and in-ocean observations with the MIT numerical ocean model to obtain realistic descriptions of how ocean circulation evolves over time. The visualization covers the period from June 2005 to December 2007.
This model is being used to quantify the ocean's role in the global carbon cycle; to understand the recent evolution of the polar oceans; to monitor time-evolving heat, water, and chemical exchanges within and between different components of the Earth system; and for many other science applications.
Ocean currents can flow for great distances, and together they create the great flow of the global conveyor belt which plays a dominant part in determining the climate of many of the Earth’s regions. Perhaps the most striking example is the Gulf Stream, which makes northwest Europe much more temperate than any other region at the same latitude. Another example is the Hawaiian Islands, where the climate is cooler (sub-tropical) than the tropical latitudes in which they are located, due to the effect of the California Current.
These model-data syntheses are among the largest computations of their kind ever undertaken. They are made possible by high-end computing resources provided by NASA's Ames Research Center in Moffett Field, Calif.
Article continues at http://www.jpl.nasa.gov/news/news.cfm?release=2012-099&rn=news.xml&rst=3333
Perpetual Ocean image via NASA