1908.] 



PHYSICAL GEOGRAPHY MACKENZIE RIVER. 



35 



These figures show that the winter climate of the upper and lower 

 Mackenzie varies but slightly, while the summer climate is consid- 

 erably cooler to the northward. 



Summaries of temperatures taken at Fort Good Hope, Mackenzie, during the 



year 1900. 



Month. 



Extremes. 



Monthly 

 mean. 



Month. 



Extremes. 



Monthly 

 mean. 



Maximum. 



Minimum. 



Maximum.! Minimum. 



January 



11.0 

 6.0 

 24.0 

 48.0 

 56.0 

 80.0 

 83.0 



-62.0 

 -46.0 

 -47.0 

 -20.0 

 14.0 

 29.0 

 39.0 



-35.7 

 -26.1 ' 

 - 7.6 , 

 19.5 

 37.2 

 56.6 

 59.6 



August 



75.0 23.0 

 60.0 1 12.0 

 34.0 i -22.0 

 21.0 -47.0 

 - 6.0 1 -.50.0 



49.2 

 37.9 

 12.3 

 -15.9 

 -24.3 



February 



March 



April 



September 



October 



November 



December 



June 



Tear _ _ 



July 



83.0 : -62.0 



13.6 





! 





Summaries of temperatures taken at Fort McPherson, MaeJcenzie, during the 



year 1900. 



Month. 



Mean daily 

 maximum. 



Mean daily 

 minimum. 



Extremes. 

 Maximum. Minimum. 



Monthly 

 mean. 



January 





-22.4 



-37.6 



16.7 



-60.6 



-30.0 



February 





-14.8 



-31.2 



6.0 



-47.4 



-23.0 



March 







5.3 



-14.6 



35.0 



-47.2 



- 4.7 



April 





24.2 



2.6 



o2 . 5 



-22.0 



13.4 



May 





31.8 



20.4 



48.9 



5.0 ! 



26.1 



June - 





60.2 



40.8 



85.0 



26.8 



50.5 



Summaries of temperatures taken at Herschel Island, Mackenzie, during the 



year 1900. 





Mean daily 





Extremes . 





Month. 



Mean dai^y 







Monthly 



maximum. 



minimum. 



Maximum. 



Minimum. 



mean . 



January _ _ _ _ _ 



-17.1 



-28.2 



18.9 



-49.4 



-22.6 



February 



-12.2 



-24.6 



11.5 



-35.2 



-18.4 



March _ _ _ 



- .1 



-15.2 



25.4 



-39.4 



- 7.6 



April 



9.9 



- 3.5 



27.2 



-2a. 4 



3.2 



May 



22.6 



11.8 



35.3 



- 1.0 



17.2 





43.2 



31.1 



00.2 



18.7 



37.1 



July 



48.7 



36.6 



62.3 



29.6 



42.7 



August 



43.5 



33.4 



62. S 



28.9 



38.4 





38.3 



29.3 



55.9 



17.3 



33.8 



October 



17.6 



9.1 



88.7 



-10.5 



13.4 



November 



5.4 



- 9.2 



34.2 



-27.8 



- 1.9 



December 



-11.7 



-23.1 



- 1.5 



-42.6 



-17.4 



Year 







62.8 



-49.4 



9.8 













As has been stated, the warm winds from the Pacific sometimes 

 exert a decided though temporary influence on the climate of the 

 Mackenzie, and the Liarcl, opening early, disrupts the ^lackenzie ice 

 below the confluence. The removal of the icy covering of an immense 

 river and the blending with its flood of the waters of a warmer tribu- 

 tary necessarily affect conditions along its banks. The ice in the 

 Liard, having broken its bonds, is forced against that of the Mac- 

 kenzie, through which it opens a passage, and urged on by the 



