On the Steep South-Facing Slopes
In early April the sun rises in the day to a maximum of 47 degrees, with the daytime average in the range of 25 to 45 degrees, relative to flat ground. that means that the sun’s rays are angled, resulting in less heat transfer to the valley floor. But on steeper south-facing slopes, the sun’s rays are direct. Any slope that has a south-facing 45 degree gradient receives 90 degree radiation in the mid-part of the day.
In the Kamloops River Valleys we have steeper south-facing slope gradients on the north side of the South Thompson River and the Thompson River on the slopes up into the Batchelor Hills, on the slopes up Mara Mountain, on the slopes of the Mt. Peter – Mt. Paul Ridge, and on the slopes from the lake up to the Dewdrop Range. Forest cover dampens the effects of direct sun’s rays, but these slopes are open and the vegetation reflects the drying effects of the sun’s rays. These slopes have sagebrush, grasses, cactus, saskatoons, and some early season wildflowers. If we hike these slopes in April, wildflowers, flowering shrubs, pollinators, and birds that feed on the insects appear earlier than in forested areas.
All photos by the author. Click an image for a lightbox view and caption.
As we climb the south-facing slopes, we may crest the slope and hike on plateau, hilltop, or bowl areas that receive angled suns rays, resulting in slower snowmelt, longer periods of wet areas/mud, and later development of vegetation. Trees become more abundant and the flora and fauna is consistent with a different ecosystem.
Hiking from the valley up into the hills means moving through transition zones and varied ecosystems.
Doug Smith
Doug writes for Kamloops Trails, a not-for-profit (and ad free) website, offering information on trails, waterways, routes, featured spots, viewpoints, and explorations in the outdoors in the Kamloops area (and beyond).
Doug started exploring this area in 1976 and continues to follow tracks and routes wherever they lead, with the aid of map, compass, GPSr and camera. After many dead-ends, but also many discoveries, he chose to share this information.
The Kamloops Trails website has a massive number of interesting posts and would be of interest to anyone in Kamloops who enjoys the outdoors. Visit the Kamloops Trails website at: http://www.kamloopstrails.ca/
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