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HYDROGRAPHIC MANUAL 



Page 578 



most of the year, and only during warm months with clear skies will the heat absorption 

 be sufficient to form a summer thermocline. 



In high latitudes as winter approaches, the summer thermocline begins to dis- 

 appear. The surface water begins "to cool, and the consequent change in density causes 



100 



200 



300 



400 



500 



600 



700 



800 



900 



1000 



TEMPERATURE DEGREES CENTIGRADE 



10 15 20 



25 



30 



Figure 130. — Range of temperature curves in offshore ocean waters. 



