Assessing Ice Island Drift Patterns, Ice Island Grounding Locations, and Gridded Bathymetry Products between Nares Strait and the North Atlantic

Аннотация

Large, tabular icebergs known as “ice islands” frequently transit the eastern Canadian Arctic and sub-Arctic after breaking away from ice tongues in northern Greenland. Here, we mine the Canadian Ice Island Drift, Deterioration and Detection (CI2D3) Database to contribute a descriptive assessment of the drift and grounding locations of Petermann ice islands (PII) following calving events at the Petermann Glacier in 2008, 2010, and 2012. We also use the CI2D3 Database to demonstrate how gridded bathymetry products can be improved using observations of ice island grounding and knowledge of ice island thickness. We find that most PII fragments followed a common southbound drift route directed by outflow from the Arctic Ocean and the dominant Baffin and Labrador Currents, which are strongest along the steep continental shelf break. Smaller ice islands were more prone to drift into the deeper waters of central Baffin Bay. As previously noted by northern community members, ice islands were also observed to drift into many adjacent sounds, channels, inlets, and straits. PIIs often grounded on shoals in Kane Basin, to the east of Coburg Island, and along the southeast coast of Baffin Island. Potential inaccuracies in two gridded bathymetry products were located in Jones Sound, near Coburg Island, and along the east coast of Baffin Island. Our approach to identifying these potential inaccuracies is shown to be sensitive to the estimate of ice island keel depth. Overall, this work provides synthesized observations of ice island occurrence and grounding as well as an approach to improving bathymetry products in a resource-rich marine region where traffic and industry operations are increasing.