NO. 17.] 



TEMPERATURE OF THE AIR AROUND THE NORTH POLE. 



575 



The calculated mean temperature for July at the Pole being above the 

 melting-point of ice is probably only to be regarded as a result of computation. 

 The chart gives only 1. 



The annual Range of the temperature is shown on the chart, PI. X. 

 Maximum 66, in Siberia; then comes North America with 45, the North 

 Pole with 42, and Greenland with 40. Minimum on the Atlantic and Pacific 

 oceans. The North Pole has a continental climate. 



The annual migration of the isotherm for C. is shown on the two 

 charts, PI. XX, one for the movement in the first part of the year towards 

 the Pole, and one for the movement in the latter part of the year from the 

 Pole. July is represented on both charts. The open Atlantic Ocean shows 

 a very small movement of the isotherm for in the winter months. 



In order to draw the isdbnormal lines resulting from the temperature- 

 charts, I first computed the normal or mean temperature for the latitudes 

 60, 65, 70, 75, 80 and 85 by taking out from the original charts, drawn 

 on a larger scale, the temperature for each of these parallels and for each 

 10 of longitude, and taking the mean for each parallel of the respective 36 

 values. The result of this computation is shown in the following Table. 



NORMAL TEMPERATURE FOR LATITUDES 



For each 5 th degree of latitude and respective 10 th degree of longitude, 

 the difference between the temperature of each point and the normal temper- 

 ature of the parallel was taken and put down on charts for each month and 



