Little Ice Age Snow-Cover Extent and Paleoglaciation Thresholds: North-Central Baffin Island, N.W.T., Canada

On air photographs, light-colored areas representing reduced lichen cover indicate the maximum extent of permanent snow cover in the recent past. Lichen-free areas were mapped on 1:50,000, 1:250,000, and 1:1,000,000 map sheets of north-central Baffin Island using air photographs and LANDSAT-1 satellite imagery. Present ice and lakes cover 37% of the study area (97,000 km2). During the Little Ice Age (350 to 100 yr BP), ice and lakes covered about 50% of the study area-an increase of 35%. The amount of lichen-free area is greatest in the elevational range of 450 to 600 m a.s.l. A limited amount of lichenometrical measurements indicate that the lichen-free areas probably represent a period of more extensive