Surface brightness contrasts accentuated by a thin layer of snow enable a
network of rivers, roads, and farmland boundaries to stand out clearly
in these MISR images of southeastern Saskatchewan and southwestern Manitoba.
The lefthand image is a multi-spectral false-color view made from the
near-infrared, red, and green bands of MISR's vertical-viewing (nadir)
camera. The righthand image is a multi-angle false-color view made from
the red band data of the 60-degree aftward camera, the nadir camera, and the
60-degree forward camera. In each image, the selected channels are
displayed as red, green, and blue, respectively. The data were acquired
April 17, 2001 during Terra orbit 7083, and cover an area measuring about
285 kilometers x 400 kilometers. North is at the top.
The junction of the Assiniboine and Qu'Apelle Rivers in the
bottom part of the images is just east of the Saskatchewan-Manitoba
border. During the growing season, the rich, fertile soils in this area
support numerous fields of wheat, canola, barley, flaxseed, and rye. Beef
cattle are raised in fenced pastures. To the north, the terrain becomes more
rocky and forested. Many frozen lakes are visible as white patches in the
top right. The narrow linear, north-south trending patterns about a third
of the way down from the upper right corner are snow-filled depressions
alternating with vegetated ridges, most probably carved by glacial flow.
In the lefthand image, vegetation appears in shades of red, owing to its
high near-infrared reflectivity. In the righthand image, several forested
regions are clearly visible in green hues. Since this is a multi-angle
composite, the green arises not from the color of the leaves but from the
architecture of the surface cover. Progressing southeastward along
the Manitoba Escarpment, the forested areas include the Pasquia Hills,
the Porcupine Hills, Duck Mountain Provincial Park, and Riding Mountain
National Park. The forests are brighter in the nadir than at the oblique
angles, probably because more of the snow-covered surface is visible in the
gaps between the trees. In contrast, the valley between the Pasquia and
Porcupine Hills near the top of the images appears bright red in the lefthand
image (indicating high vegetation abundance) but shows a mauve color in the
multi-angle view. This means that it is darker in the nadir than at the oblique
angles. Examination of imagery acquired after the snow has melted should
establish whether this difference is related to the amount of snow on the
surface or is indicative of a different type of vegetation structure.
Saskatchewan and Manitoba are believed to derive their names from the
Cree words for the winding and swift-flowing waters of the Saskatchewan
River and for a narrows on Lake Manitoba where the roaring sound of wind
and water evoked the voice of the Great Spirit. They are two of Canada's
Prairie Provinces; Alberta is the third.
Image credit: NASA/GSFC/LaRC/JPL, MISR Team.
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