igii] The Climate of Northern Ontario. 149 



THE CLIMATE OF NORTHERN ONTARIO. 

 By R. F. Stupart, Esq. 



{Read 2gth March, 191 1.) 



That portion of the Province of Ontario which lies north of and im- 

 mediately south of the Canadian Pacific Railway has been the subject 

 of much enquiry as to climate, but it is only within the past few years 

 that reports from the Government Meteorological stations have made it 

 possible to give any conclusive information as to the climatic conditions 

 of this large section of the Province. The Territory in question com- 

 prises the districts of Nipissing and Algoma and extends northward from 

 Lakes Superior and Huron and Lake Nipissing to James Bay and the 

 Albany River. The stations from which data are available are Calvin 

 near Lake Nipissing, Haileybury on the west shore of Lake Temiskaming, 

 Lake Abitibi, White River, north of Lake Superior, Fort Hope on 

 the Albany River and Moose Factory. 



As the agricultural possibilities of a region depend chiefly on the 

 length of the summer season and the intensity of the heat during that 

 season, it is the period between May ist, and September 15th, that is of 

 primary importance. 



A perusal of the accompanying tables will shew that even in the 

 extreme north the summer is fairly warm. At Moose Factory and Fort 

 Hope the average daily maxima temperatures for July and August are 

 74° and 70° as against 77° and 73° at Haileybury which latter tempera- 

 tures are almost the same as those at Toronto in the same months. It 

 will however be observed that in June the temperature is considerably 

 lower in the north than at Haileybury and Toronto and that the nights 

 are cooler all through the summer. Temperatures of over 80° are not 

 infrequent in Northern Ontario and 90° and over usually occur one or 

 more times in each summer. 



All Meteorological records in the interior and in eastern Canada 

 show that temperature differences resulting from difference in latitude 

 are much greater in winter and spring than in the summer and early 

 autumn, and this fact has a strong bearing on the character of the cli- 

 mate of the region under discussion. At midwinter the temperature 

 is fully 12° lower on the mean at the northern boundary of Ontario than 

 near Lake Nipissing. By May the difference has been diminished to 

 9° and in June, the southern district still averages 6.5° higher than the 

 northern. In July and August however, the mean temperatures of the 

 two districts only differ by 3° and it is October before there is any very 

 marked divergence of the temperature curves. These facts go to shew 

 that it is the late spring and the liabiHty to June frost that will be the 



