Oceanic Boundary Conditions for Jakobshavn Glacier. Part II: Provenance and Sources of Variability of Disko Bay and Ilulissat Icefjord Waters, 1990–2011

Jakobshavn Glacier's response to temperature changes in Ilulissat Icefjord is influenced by the exchange of basin waters with neighboring Disko Bay, which occurs at least annually. The study reveals that the warm Atlantic-origin core of the West Greenland Current does not penetrate deep into Disko Bay or the fjord due to bathymetric impediments on the west Greenland shelf. Instead, the fjord basin is filled by an equal mix of Atlantic water and less-saline polar water, with the latter often originating from the East/West Greenland Current but sometimes from the colder Baffin Current. The annual temperature cycle of the West Greenland Current does not propagate into deep Disko Bay or the fjord basin due to depressed isopycnals during warm autumn/winter phases. Anomalously cool conditions in Ilulissat Icefjord during summer 2010 were linked to high freshwater flux through the Canadian Arctic and a weak West Greenland Current, allowing cold Baffin Current water to flood the shelf. Conversely, record warm waters in Disko Bay and Ilulissat Icefjord in 2011/12 were attributed to subpolar gyre warming associated with a negative North Atlantic Oscillation (NAO) index during winter 2009/10.

Gladish, C. V., Holland, D. M., & Lee, C. M. (2015). Oceanic Boundary Conditions for Jakobshavn Glacier. Part II: Provenance and Sources of Variability of Disko Bay and Ilulissat Icefjord Waters, 1990–2011. Journal of Physical Oceanography, 45(1), 33–63. https://doi.org/10.1175/jpo-d-14-0045.1