Description :
The nature of the ice cover comprised in road lanes varies as a function of construction and maintenance practices. Snow removal, to stimulate ice growth, is among the first steps of the construction process. At this particular location, the ice was measured to be about 143 cm thick - some 40 cm thicker than nearby off-road ice. The top 11 cm of this ice cover appears to be man-made as it includes alternating snow ice and columnar ice layers - a sign of intentional flooding. The tone of ice roads lanes in RADARSAT-2 multi-polarization image composites ranges from purple to pink to white depending on variability in
ice type composition, surface roughness, crack levels, etc.
Photographe :
van der Sanden, J J
Collection :
Ressources naturelles Canada
Haute-résolution :
5.16 MB
4928x3264 pixels
300 ppi (jpeg)
Nota :
Depending on the weather conditions, ice cover can grow the full extent of the available water depth and become attached to the lake bottom. Unfortunately, bottom-fast ice cannot be discriminated from floating columnar ice in individual RADARSAT-2 multi-polarization composite images because both ice types display black. Discrimination of the two ice types is facilitated by a times series of RADARSAT-2. The measured backscatter level
decreases when the ice becomes bottom-fast and increases when the ice grows. Similar to shorelines, bottom-fast ice formations jeopardize the trafficability of ice roads because their presence increases the risk of traffic induced ice cover failures. However, the presence of bottom-fast ice is more difficult to ascertain.
Géographie :
5289; Tibbitt-to-Contwoyto Winter Road; Territoires du Nord-Ouest; 2020-345.JPG; Nunavut