Lake Temperatures 



33 



disturb the horizontal uniformity, and winds may do 

 much to disturb the regularity of gradations toward the 

 surface. Water temperatures are primarily dependent 

 on those of the superincumbent air. The accompany- 

 ing diagram of comparative yearly air and water 

 temperatures in Hallstatter Lake (Austria) shows 

 graphically the diminishing influence of the former on 

 the latter with increasing depth. 



I 



10 



'O - 



>s- 



o- 

 -6. 



10'- 



o- 



10- 

 Cf- 



o- 



10- 



J- 

 o- 



6- 

 o 



60 



1OO 



s- 



o- 



O 



FIG. 5. Diagram illustrating the relation of air and water temperatures at 

 varying depths of water in Hallstatter Lake (after Lorenz). 



