CGRG Bibliography of Canadian Geomorphology
Search Results
Author : Andrews, J.T., Davis, J.T. and Wright, C.
Date : 1976.
Title : Little Ice Age permanent snow cover in the eastern Canadian Arctic: Extent mapped from LANDSAT-1 satellite imagery
Publication : Geografiska Annaler
Issue : 58A:
Page(s) : 71-81
Abstract
Extensive areas of the eastern Canadian Arctic are light grey/white on both conventional black and white air photography and on muiti-spectral LANDSAT-1 satellite imagery. These areas stand out in marked contrast to the darker toned surrounding terrain. Field investigations indicate that the light grey areas possess few lichens or plants, in contrast, their margins abut terrain with a mature lichen cover. Areas within the lichen trimlines are interpreted as the sites of former permanent snowbeds and snowfields. Radiometrlc and lichenometric dates indicate that the episode of permanent snowfields occurred about 500 to 300 years ago with retreat starting between 300 and 70 years ago. The LANDSAT-1 satellite lmagery at a scale of 1:1 000 000 has proven ideal for mapping the regional extent of this former snowcover and this is illustrated by two frames from northcentral Baffin Island. Interpretation problems can arise from a number of sources, such as: light early summer or fall snowcover, limestone bedrock, recent outwash plains, and low clouds. However, ambiguities can be eliminated by inspection of LANDSAT-l frames from different passes, by the examination of 1:60 000 air photographs, by the use of 1:250 000 scale contour maps, and by comparison with maps of the bedrock geology.
Bibliography of Canadian Geomorphology