RECORD OF BLIZZARDS 



323 



This factor is the blizzard. Superimposed upon the normal 

 winds are the blizzard winds having velocities varying from 10 

 miles an hour up to over 60, in consequence of which high winds 

 occur with a frequency out of all proportion to what would have 

 occurred if there had been no blizzards. 



Thus the shape of the wind curve for Cape Evans shows 

 clearly that the blizzard is an abnormal phenomenon superposed 

 upon the ordinary meteorological conditions, and the curve for 

 Framheim that it does not occur there. 



The cause of the blizzards, their frequency, and the extent 

 of country affected by them will be fully discussed in the scientific 

 reports of the Expedition; here one is only interested in them 

 in so far as they affected the fortunes of the members of the 

 Expedition. The following table gives the number of hours 

 blizzard winds were recorded at Cape Evans and the mean 

 temperature recorded while the winds were blowing. 



TABLE III. 



Number of blizzards recorded at Cape Evans 

 A blizzard is taken as a southerly wind of 25 miles an hour or 



over. 



