ANTARCTIC ADVENTURE AND RESEARCH 



about 739.7 mm. It is also well known that these belts 

 are to a considerable degree the tracks of moving 

 eddies (cyclones and anticyclones) which in general 

 move to the east round the earth at varying rates 

 averaging perhaps four hundred miles a day. 



Fig. 2y. — Atmospheric circulation in the southern 



HEMISPHERE SOUTH OF THE TRADE WIND BELT, ACCORDING 



TO THE "Polar front" theory, showing the belt 

 OF LOWS (L) surrounding the Antarctic anti- 

 cyclone (H). 



(Slightly modified from E. Kidson.) 



It is when we consider the world circulation to the 

 south of the Antarctic Circle that our data become 

 sparse and rather difficult to interpret. In the older 

 books it was assumed that the pressure fell off to a 

 minimum near the South Pole. When the presence 



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