Characteristics of meltwater export from Jakobshavn Isbræ and Ilulissat Icefjord

A study of Jakobshavn Isbræ, the fastest retreating glacier in Greenland and a significant contributor to ice-sheet mass loss, reveals that its meltwater export forms a buoyant coastal gravity current extending 10 km offshore and reaching depths of 100 meters. The research, conducted using hydrographic observations and inert geochemical tracers, provides the first quantitative description of glacially-modified waters exported from the Jakobshavn/Ilulissat Icefjord system. These waters contain submarine meltwater (up to 2.5 ± 0.12%) and subglacial discharge (up to 6 ± 0.37%), along with entrained ocean waters, suggesting a deep-reaching overturning cell driven by glacial buoyancy forcing. The findings highlight the potential impacts of increased freshwater discharge on ice melt feedbacks, marine ecosystems, and regional ocean circulation.

Beaird, N., Straneo, F., & Jenkins, W. (2017). Characteristics of meltwater export from Jakobshavn Isbræ and Ilulissat Icefjord. Annals of Glaciology, 58(74), 107–117. https://doi.org/10.1017/aog.2017.19