In a recent study that quantified glacier area changes across Northern Ellesmere Island, White and Copland ( Reference White and Copland2018) reported the loss of 19 out of 27 ice tongues between ~1999 and ~2015, located predominantly in the Yelverton Bay region. Since 2005, the coastline has undergone rapid and extensive changes in its floating ice cover, including nearly complete loss of the Ayles, Markham and Serson ice shelves, and the complete loss of >70 year old MLSI from Yelverton Bay, Yelverton Inlet and Kulutingwak Fiord (Copland and others, Reference Copland, Mueller and Weir2007 Mueller and others, Reference Mueller, Copland, Hamilton and Stern2008, Reference Mueller, Copland, Jeffries, Copland and Mueller2017 Pope and others, Reference Pope, Copland and Mueller2012 White and others, Reference White, Copland, Mueller and Van Wychen2015). The ice shelves are remnants of a 500 km long ice shelf (unofficially named the Ellesmere Ice Shelf) that fringed the northern coast of Ellesmere Island at the start of the 20th century, which initially formed through the thickening of MLSI and sometimes glacial input (Vincent and others, Reference Vincent, Gibson and Jeffries2001). In the Canadian Arctic Archipelago (CAA), the northern coast of Ellesmere Island is unique for having a coastline characterized by tidewater glaciers that include floating glacier tongues (hereafter referred to as ice tongues) and ice shelves, typically fringed by multi-year landfast sea ice (MLSI). Without the sustained presence of MLSI in this region the ice tongues are unable to stabilize, making it unlikely that they will re-form in the current climate. Despite the recent return of ocean temperatures to below pre-2006 levels, atmospheric summer temperatures have continued to rise (+0.15☌ decade −1 between 19), with open water continuing to occur. These changes were accompanied by an increase in mean annual mid-depth (i.e. The loss of ice tongues since 2005 occurred when open water replaced multi-year landfast sea ice (MLSI) and first-year sea ice in the regions adjacent to the ice tongues. From 1959 to 2017, the total ice tongue area decreased by 49.07 km 2, with the majority of this loss occurring from 2005 to 2009 (34.68 km 2). sea ice, sikussak and mélange), and atmospheric and oceanographic forcings. To better understand the causes of these losses, this study undertakes the first examination of ice tongue changes in this region, including an assessment of changes in surrounding marine ice (i.e. A total of eight floating glacier tongues have shrunk in area by >85% from the Yelverton Bay region of Northern Ellesmere Island since 1959, with unusually large losses since 2005.
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