128 



WIND. 



A remarkable characteristic of southerly winds was the suddenness witii which they often 

 commenced. Three typical examples are shown in figure 46. One would expect that such 



t 



70 W 



J 



I 



c 



60 - 



> 



so ? 



40 z 



i 



April 2Qth. m 



May S/st. m. 

 Fig. 46. Sudden setting in of blizzards. 



September 1st. tSll 



a sudden change in wind conditions would be connected with a sudden change in the baro- 

 meter. The relationship between the barometer and blizzards will be discussed in the chapter 

 on blizzards, but it may be mentioned here that there is no obvious connection between the 

 sudden commencement of a blizzard and the barometer. In fact it would be quite impossible 

 to say when a sudden commencement of a blizzard occurred from the barograph trace 

 although in some cases there was an almost instantaneous rise m the wind velocity of over 

 30 miles an hour.* 



Cape Adare wind.s. 



The winds at Cape Adare are one of the paradoxes of the Antarctic. We have already 

 seen that the frequency of light winds is very high. The Beaufort Scale was used for 

 estimating the wind strength and from March to September, 1911, 693 per cent, of all the 

 observations were recorded as either or 1 on this scale. In other words, during considerably 

 more than half the time there was practically no wind. On the other hand Cape Adare 

 was visited by winds of hurricane strength. The observers were experienced men and were 

 not inclined to overestimate the wind strength, yet there are many estimates of wind 

 strength of 11 and 12 on the Beaufort Scale. 



WTjen forwarding the meteorological records of Cape Adare, Priestly sent to me a personal 

 letter. This was not intended for publication, nor was it intended as a contribution to science, 

 yet it would be impossible to give a clearer idea of the conditions during these storms than 

 is contained in this colloquial description, and this must be my excuse for quoting from it 

 here. 



* In a few instances a very slight discontinuity in the barograph trace accompaniod a sudden change in the 

 wind velufitv. but in most cases even this was absent. 



