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 The Global Conveyor Belt Currents Tutorial This animation shows the path of the global conveyer belt. The blue arrows indicate the path of deep, cold, dense water currents. The red arrows indicate the path of warmer, less dense surface waters. It is estimated that it can take 1,000 years for a "parcel" of water to complete the journey along the global conveyor belt.
   Cold, salty, dense water sinks at the Earth's northern polar region and heads south along the western Atlantic basin.    The current is "recharged" as it travels along the coast of Antarctica and picks up more cold, salty, dense water.    The main current splits into two sections,  one traveling northward into the Indian Ocean, while the other heads up  into the western Pacific.    The two branches of the current warm and rise as they travel northward, then loop back around southward and westward.    The now-warmed surface waters continue  circulating around the globe. They eventually return to the North  Atlantic where the cycle begins again.
 Thermohaline circulation drives a global-scale system of currents called the   “global conveyor belt.” The conveyor belt begins on the surface of the ocean   near the pole in the North Atlantic. Here, the water is chilled by arctic   temperatures. It also gets saltier because when sea ice forms, the salt does not   freeze and is left behind in the surrounding water. The cold water is now more   dense, due to the added salts, and sinks toward the ocean bottom. Surface water   moves in to replace the sinking water, thus creating a current. This deep water moves south, between the continents, past the equator, and down   to the ends of Africa and South America. The current travels around the edge of   Antarctica, where the water cools and sinks again, as it does in the North   Atlantic. Thus, the conveyor belt gets "recharged." As it moves around   Antarctica, two sections split off the conveyor and turn northward. One section   moves into the Indian Ocean, the other into the Pacific Ocean. These two sections that split off warm up and become less dense as they travel   northward toward the equator, so that they rise to the surface (upwelling). They   then loop back southward and westward to the South Atlantic, eventually   returning to the North Atlantic, where the cycle begins again. The conveyor belt moves at much slower speeds (a few centimeters per second)   than wind-driven or tidal currents (tens to hundreds of centimeters per second).   It is estimated that any given cubic meter of water takes about 1,000 years to   complete the journey along the global conveyor belt. In addition, the conveyor   moves an immense volume of water—more than 100 times the flow of the Amazon   River (Ross, 1995). The conveyor belt is also a vital component of the global ocean nutrient and   carbon dioxide cycles. Warm surface waters are depleted of nutrients and carbon   dioxide, but they are enriched again as they travel through the conveyor belt as   deep or bottom layers. The base of the world’s food chain depends on the cool,   nutrient-rich waters that support the growth of algae and seaweed.
  Currents Lessons  Welcome		  	
Tidal Currents 1  
Tidal Currents 2
    
    Coastal Currents

	Waves
    Longshore Currents
    Rip Currents
    Upwelling
    
    Surface Ocean Currents

	    The Coriolis Effect
        Surface Ocean Currents
        Boundary Currents
        The Ekman Spiral

    The Global Conveyor Belt

	  Thermohaline Circulation
	  The Global Conveyor Belt
	  Effects of Climate Change

    How Are Currents Measured?


    Age of Exploration
	What is a "knot"?
    Shallow Water Drifter
    Deep Ocean Drifter
    Current Profiler
    Shore-based Current Meters
   
How Currents Affect Our Lives?
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