The ice shelves along the northern coast of Ellesmere Island have been in a state of decline since at least the early 20th century. Available data derived from explorers' journals, aerial photographs and satellite imagery have been compiled into a single geospatial database of ice shelf and glacier ice tongue extent over 13 observation periods between 1906 to 2015. During this time there was a loss of 8,061 km² (94%) in ice shelf area. The vast majority of this loss occurred via episodic calving, in particular during the first six decades of the 20th century. More recently, between 1998 and 2015, 515 km² of shelf ice calved. Some ice shelves also thinned in situ, transitioning to thinner and weaker ice types that can no longer be considered ice shelf, although the timing of this shift is difficult to constrain with the methods used here. Some ice shelves composed partly of ice tongues (glacier or composite ice shelves) also disintegrated to the point where the ice tongues were isolated, representing a loss of ice shelf extent. Our digitization methods were typically repeatable to within 3%, and generally agreed with past determinations of extent. This research highlights the fact that the break-up of these massive features is an ongoing phenomenon. It is hoped that this comprehensive dataset will provide a basis for comparison of future changes in this region.
[Abstract from Mueller DR, Copland L, Jeffries MO (2017) Changes in Canadian Arctic ice shelf extent since 1906. In: Copland L, Mueller DR (eds) Arctic Ice Shelves and Ice Islands, Springer, Dordrecht]
