4. precipitation that is warmer than the surface layers of the ocean. 



The main processes that lower the temperature of surface layers of the ocean are as follows: 



1. radiation from ocean to the atmosphere, 



2. evaporation, 



3. convection of the atmosphere, 



4. precipitation that is colder than the ocean surface, 



5. ice melting. 



The main processes that increase the salinity of surface water layers are as follows: 



1. evaporation, 



2. ice formation. 



The main processes that decrease the salinity of surface water layers are as follows: 



1. precipitation, 



2. condensation of water vapor on the ocean surface, 



3. ice melting. 



In addition to these main processes, there are processes that are constantly active in the 

 sea — changing its temperature and salinity, but being of considerably smaller significance. These 

 processes are as follows: 



1. transformation of the mechanical energy of wind, currents and tidal phenomena into heat 

 energy, which results from friction and occurs at all depths, 



2. biochemical processes which change, to a degree, the temperature and salinity and occur 

 at all depths , 



3. absorption of the earth's heat by deep water layers. The earth's heat, as well as the 

 radioactivity of the bottom, explains evidently the somewhat higher temperatures of almost im- 

 mobile bottom layers of the oceans and several landlocked seas . 



The main processes that affect the temperature and salinity of ocean surface layers in ocean- 

 ological coordinates do not occur independently from one another. On the contrary, they usually 

 occur simultaneously, whereby part of them act in one direction and others the reverse direction. 

 For instance, the warming of the sea surface intensifies evaporation which, in turn, cools the sur- 

 face layers. Not only does this evaporation cool the ocean surface layers, but simultaneously it 

 also increases their salinity, etc. The intensity of each of the processes that affect the tempera- 

 ture and salinity of the surface layers of the ocean does not remain constant; sometimes one of the 

 processes prevails and at other times another. In this connection, the temperature and salinity 

 of the ocean is now increasing, now decreasing. Thus the final effect of temperature and salinity 



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