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NATURALIST'S GUIDE TO THE AMERICAS 



glaciation and subsequent stream ero- 

 sion has considerably modified the 

 topography. Valleys were enlarged and 

 lowered, soil deposited, and lakes formed 

 — all matters of importance to forestry, 

 agriculture, and transportation today. 

 The soil is largely formed of these 

 deposits of glacial drift. It is estimated 

 that of the total area about 47 per cent 

 is suitable for agriculture, grazing or 

 the production of timber, while 53 per 

 cent is above merchantable timber-line, 

 is water surface or swamp land, or is 

 incapable of growing timber of any com- 

 mercial value on account of ruggedness. 



B. CLIMATE 



The chief factors for consideration in 

 relation to climate area: Influence of 

 Japan Current; the 11 degrees of latitude 

 through which the Province extends; the 

 extremes of altitude from sea level to 

 13,500 feet (Mount Robson). 



The principal topographic features 

 have a general trend at right angles to 

 the prevailing winds. Warm moisture- 

 laden air-currents sweep inland from 

 across the Japan Current, to be chilled 

 as they ascend the western slope of the 

 mountain ranges and are forced to 

 deposit their moisture. As they cross 

 the summit to the warm eastern slope 

 they become comparatively dry, to be 

 again chilled as they cross the next 

 range. The result is alternating wet and 

 dry belts, the wet belts occurring again 

 and again on the main Rockies, while 

 the Interior plateau and the east slope 

 of the Selkirks are comparatively dry. 

 These winds also moderate extremes of 

 temperature. The main climatic re- 

 gions are as below: 



Lower Coast Belt. Characterized by 

 mild, even temperature and a variation 

 of only 30° between summer and winter 

 mean. The summer isotherm on which 

 the region is situated would pass through 

 Quebec, Edinburgh, and Southern 

 Norway; the winter through New York 

 and London. The precipitation aver- 

 ages 60 to 70 in., of which one third 



occurs during the summer season; the 

 record of bright sunshine averaging 

 about 2000 hours per year. 



North Coast Belt. Averages some 5° 

 lower in mean temperature throughout 

 the year and has an increased precipita- 

 tion, this being 110 in., one-quarter of 

 which falls during the summer season. 

 A part of the winter precipitation falls 

 in the form of snow. 



Interior Plateau or Dry Belt. Charac- 

 terized by greater variations of tempera- 

 ture and a relatively limited precipita- 

 tion. Typical Stations show: 



This region is on the same isotherm as 

 Toronto and Central Europe, Warsaw, 

 during January; New York or Paris 

 during July. The record of bright sun- 

 shine is 200 and 2200 hrs. 



Second Wet Belt. This has relatively 

 the same temperature range as the Dry 

 Belt, but greater precipitation. 



The first two stations are valley sta- 

 tions and the last two hill stations; the 

 elevation of Barkerville being 4180 ft. 

 and Glacier 3778 ft. 



Second or Columbia Dry Belt. This 



