H    
Water World
 
                                       
       
Ocean Circulation
 
                                       
      ThermoHaline Circulation
       

    The global conveyor belt thermohaline circulation is driven primarily by the formation and sinking of deep water (from around 1500m to the Antarctic bottom water overlying the bottom of the ocean) in the Norwegian Sea. This circulation is thought to be responsible for the large flow of upper ocean water from the tropical Pacific to the Indian Ocean through the Indonesian Archipelogo.
    The two counteracting forcings operating in the North Atlantic control the conveyor belt circulation:
(1) thermal forcing (high-latitude cooling and the low-latitude heating) which drives a polar southward flow; and
(2) haline forcing (net high-latitude freshwater gain and low-latitude evaporation) which moves in the opposite direction.

  
                                       
       
    In today's Atlantic the thermal forcing dominates, hence, the flow of upper current from south to north. When the strength of the haline forcing increases due to excess precipitation, runoff, or ice melt the conveyor belt will weaken or even shut down. The variability in the strength of the conveyor belt will lead to climate change in Europe and it could also influence in other areas of the global ocean. The North Atlantic atmosphere-ocean-cryosphere system appears to have natural cycles of many timescales in switching the conveyor belt. Periodic movement of excessive ice from the Arctic into the Greenland Sea appears to be responsible for the interdecadal variability of the conveyor belt. There is no evidence yet that the influx of interdecadal switching extends beyond the North Atlantic Ocean. .
  
                                       
       
What drives this Circulation?
  
                                       
                          Cold Water is more dense than warm water.    
           
Difference in Density
                      
                          Salty water is more dense than freshwater.    
                                       
        Heat Convection  
                                       
        Gases are more soluble at Low Temperatures and High Pressures

  
                                       

CO2 + H2O ------> H2CO3
 
     
       
 
       
    FreshWater  
                                       
               
          No Salt. Please!  
               
                                       
          Ogallala Aquifier
      
                                       
                       
                                       
          Salton Sea    
                                       
         
    
     The Salton Sea, located in the southeastern corner of California, is actually a lake which occupies a desert basin known as the Salton Sink. This body of water covers a surface area of 376 square miles, making it larger than Lake Tahoe and Mono Lake.  In fact, the Salton Sea is the largest lake in California.  The Sea's current elevation is about 227 feet below mean sea level, its maximum depth reaches 51 feet and its total volume is about 7.5 million acre-feet.
Salton Sea Authority
Facts
SDSU
USGS
 
    
                                       
               
                                       
         
ALL COULD BE LOST

The Salton Sea’s important resources are threatened by rising salinity, excessive nutrient run-off from agriculture, pending agricultural to urban water transfers – and politics. One thing is certain, within 15 years the Salton Sea will lose 300,000 acre feet of water from its total inflow. Restoration efforts must be well underway within that 15 year timeframe in order to avoid the beginning of the end for the Salton Sea.		      
                                       
             
     As an agricultural drainage reservoir, the Salton Sea serves an important purpose for the productive agricultural valleys that adjoin it. As an agricultural sump, the Sea consists primarily of commercial agricultural drainage.  In fact, 90 percent of the entire inflow to the Sea is agricultural runoff from the Imperial, Coachella, and Mexicali Valleys.  
    This inflow carries nutrients, such as phosphates and nitrates, which support the rich and abundant life in the Sea.  The inflow also carries an abundance of salt (and thus the Sea's name). Currently, the salinity level of the Salton Sea is 44 parts per thousand (ppt), compared to 280 ppt for Utah's Great Salt Lake, about 210 ppt for Israel's Dead Sea, 87 ppt for Mono Lake and 35 ppt for the Pacific Ocean.