Assessment of historical changes (1959-2012) and the causes of recent break-ups of the Petersen ice shelf, Nunavut, Canada. Issue 69 (2015)

• Record Type: Journal Article
• Authors: White, Adrienne; Copland, Luke; Mueller, Derek; Van Wychen, Wesley
• Is Part Of: Annals of glaciology. Volume 56:Issue 69(2015)
• Page Start: 65
• Page End: 76
• Publication Date: 2015
• Subjects: Arctic glaciology, -- ice shelves, -- ice velocity, -- ice-shelf break-up, -- ice-shelf tributary glaciers; Glaciology -- Periodicals; 551.3105 qA613
• DOI: 10.3189/2015AoG69A687
• Languages: English
• ISSNs: 0260-3055

Abstract

Abstract: Aerial photography and satellite imagery of the Petersen ice shelf, Nunavut, Canada, from 1959 to 2012 show that it was stable until June 2005, after which a series of major calving events in the summers of 2005, 2008, 2011 and 2012 resulted in the loss of ∼61% of the June 2005 ice-shelf area. This recent series of calving events was initiated by the loss of extensive regions of ˃50-year-old multi-year landfast sea ice from the front of the ice shelf in summer 2005. Each subsequent calving event has been preceded by open-water conditions and resulting loss of pack-ice pressure across the front of the ice shelf, and most occurred during record warm summers. Ground-penetrating radar (GPR) ice thickness measurements and RADARSAT-2 derived observations of surface motion indicate that tributary glaciers provided total ice input of 1.19-5.65 Mta –1 to the ice shelf from 2011 to 2012, far below the mean surface loss rate of 28.45 Mta –1 . With recent losses due to calving and little evidence for current basal freeze-on, this suggests that the Petersen ice shelf will no longer exist by the 2040s, or sooner if further major calving events occur.