September in Canada is a transitional time, as the chilly autumn winds herald the leaf-color season and early snowfall in the higher elevations gives the first hint of the winter to come, while in the lowlands and the south the effects of summer drought and heat may linger. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite passed over western Canada on September 22, 2012 and captured this true-color image of the changing landscape.
Black borderlines have been overlain on the MODIS image in order to delineate boundaries. The Yukon lies in the northwest corner of this image, and the Northwest Territories lies to the east. In the southern section of this image, British Columbia lies along the Pacific Ocean, and Alberta is inland.
Fresh snowfall was reported as early as September 11 in the mountains of British Columbia, and the tall peaks of these mountains are snow-covered along the entire range. In the north, the Mackenzie Range, which forms the border between Yukon and the Northwest Territories, is also snow-topped. Further inland, a lighter dusting of snow covers the peaks of the Rocky Mountains.
In the far north, autumnal colors of yellow, light green and orange can be seen shading the landscape. A large, dark blue lake stretches near the Rocky Mountains in north-central British Columbia. This is Williston Lake, the largest lake in British Columbia, which was created in 1968 when the W.A.C. Bennet Dam was completed. To the south of the reservoir a roughly circular area of forest appears mottled green and gray. This is an area of pine forest which has been devastated by the mountain pine beetle, an insidious and spreading pest which has caused severe damage to western forests.
At least one fire, marked by a red hotspot and billowing smoke, appears in the beetle-damaged forest. Additional fires burn in northeast British Columbia and northwest Alberta, reminders of the hot, dry summer which left forests throughout western North American ripe for massive fires. Near the lower left edge of the image a broad band of smoke blows across the land and across the Pacific Ocean. This smoke originated from the fires burning in the western United States.