Shorefast Sea Ice Breakup

The formation and breakup of shorefast ice long Arctic coastlines and within fjords is one fo the most dramatic seasonal environmental changes on Earth. Unlike drift ice, which forms and moves in the open ocean, shorefast sea ice is frozen to the coast and therefore provides a perennial platform integral to the ecology, socioeconomics and culture of the pan-Arctic region. Coastal Arctic communities depend on shorefast ice for traditional subsistence activities and transportation as the ice provides a vital link between otherwise isolated villages. The ice is also a critical habitat for Arctic mammals and protects Arctic coastlines from erosion.

Shorefast sea ice occurs along coastlines and in narrow fjords and therefore cannot be resolved by the coarse passive microwave sensors typically used to monitor changes in sea ice from space. Consequently, less is known about changes in shorefast ice breakup and the processes which drive it. Using MODIS imagery, I am mapping decadal changes in the timing of shorefast ice breakup in and around coastal communities in Greenland and northern Canada. These satellite-derived estimates of breakup timing can help us understand drivers of shorefast ice breakup and how breakup timing may change in the future.

Animation of shorefast ice breakup in 2017 around Uummannaq, Greenland using Sentinel-2 imagery. Red dots show the location of the communities located in the region, from left, Qaarsut, Uummannaq, Saattut and Ikerasak.

Animation of shorefast ice breakup in 2017 around Uummannaq, Greenland using Sentinel-2 imagery. Red dots show the location of the communities located in the region, from left, Qaarsut, Uummannaq, Saattut and Ikerasak.

This research is part of a larger three-year project involving co-production of knowledge about shorefast ice in Uummannaq, North Greenland. The goal of this work, led by Jonathan Ryan at Brown and Brigt Dale at the Nordland Institute in Norway, is to combine our satellite-derived research on ice breakup with local knowledge about the sea ice and how it is changing. We conducted our first fieldwork for this project in Uummannaq in spring 2019.

The shorefast ice edge in Uummannaq Fjord, viewed from a helicopter in May 2019

The shorefast ice edge in Uummannaq Fjord, viewed from a helicopter in May 2019