Chapter 16 — FUNDAMENTALS OF OCEANOGRAPHY 



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Figure 16-9. — Surface currents of the oceans (February-March), 



be expected. The temperatures near the coast 

 are further lowered by the UPWELLING of 

 colder water from moderate depths; the upwelling 

 is caused by the prevailing winds. The upwelling 

 here is not as pronounced as at some other 

 localities. Upwelling of ocean water is the 

 process by which the colder subsurface waters 

 are brought to the top. This is made possible 

 in areas where the winds cause the surface 

 water to be transported away from the coast, 

 with the surface water being replaced by the 

 colder subsurface water. In the Northern 

 Hemisphere upwelling is common where a wind 

 blows parallel to the coast, with the coast on 

 the left side of the wind, which causes the 

 surface water to be transported to the right 

 and away from the coast. In the process of 

 upwelling, the overturn of water takes place 

 only in the upper layers (to a maximum depth 

 of about 150 fathoms). 



A branch of the SOUTH EQUATORIAL 

 CURRENT crosses the Equator from the South 

 Atlantic Ocean and joins with the North 

 Equatorial Current in the western part of the 

 North Atlantic Ocean. Consequently, the part 

 of the North Equatorial Current that enters 

 the Caribbean Sea has water that has been 

 mixed with water of the South Atlantic Ocean. 

 The northern branch of the North Equatorial 

 Current which flows along the northern side of 

 the Greater Antilles is called the ANTILLES 

 CURRENT. It carries water that is virtually 

 the same as that of the Sargasso Sea (a portion 

 of the middle North Atlantic Ocean), 



Gulf Stream System 



The northward and eastward flow of water 

 that begins in the Florida Straits is known 

 as the Gulf Stream system. These waters include 



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