Basin-scale partitioning of Greenland ice sheet mass balance components (2007–2011)

• Published in: Earth and Planetary Science Letters
• Main Authors: Andersen, M.L., Stenseng, L., Skourup, H., Colgan, W., Khan, S.A., Kristensen, S.S., Andersen, S.B., Box, J.E., Ahlstrøm, A.P., Fettweis, Xavier, Forsberg, R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier Science 2015
• Subjects: Greenland ice sheet; surface mass balance; ice discharge; Physical; chemical; mathematical & earth Sciences; Earth sciences & physical geography; Physique; chimie; mathématiques & sciences de la terre; Sciences de la terre & géographie physique; Greenland; Ice Sheet
• Online Access: https://orbi.uliege.be/handle/2268/173996; https://doi.org/10.1016/j.epsl.2014.10.015

peer reviewed The current deficit in Greenland ice sheet mass balance is due to both a decrease in surface mass balance (SMB ) input and an increase in ice discharge (D ) output. While SMB processes are beginning to be well captured by observationally-constrained climate modeling, insight into D is relatively limited. We use InSAR-derived velocities, in combination with ice thickness observations, to quantify the mass flux (F ) across a flux perimeter around the ice sheet at ∼1700 m elevation. To quantify D , we correct F for SMB , as well as changes in volume due to ice dynamics, in the area downstream of the gate. Using a 1961–1990 reference climatology SMB field from the MAR regional climate model, we quantify ice sheet mass balance within eighteen basins. We find a 2007–2011 mean D of View the MathML source. We find a 2007–2011 mean total mass balance of View the MathML source, which is equal to a 0.73 mm yr−1 global sea level rise contribution. This mass loss is dominated by SMB, which accounts for 61% of mass loss in the basins where partitioning is possible.