74 



TEMPERATURE. 



In the following table are given the mean temperature, the mean range, the amplitude, 

 and the reduced range for each month. The values for the amplitude are those given in 

 table 20, page 53, and the temperatures have been obtained from data for eaoh month 

 from four years. 



Table 32. 

 Unperiodic Temperature Variations in McMurdo Sound. 



From the column for reduced range we see that non-periodic temperature changes are 

 smallest in January and largest in July. Also by comparing the first and last columns we 

 see that the reduced range has almost the same yearly variation as the mean temperature. 



This close relationship between the non-periodic temperature changes and the mean tem- 

 perature, leads at once to the conclusion that cold weather is favourable to unsteady tem- 

 peratures while warm weather is unfavourable. If, however, we examine the reduced range for 

 any one month in difEerent years, we do not find that it follows very closely the mean 

 temperature. Thus, in the month of June the years arranged in order of increasing mean 

 temperature were 1902, 1903, 1911 and 1912, but in order of decreasing reduced range they 

 are 1903, 1902, 1912, 1911, the data are as follows:— 



Table 33. 



