Timing and origin of recent regional ice-mass loss in Greenland
Research output: Contribution to journal › Journal article › Research › peer-review
Within the last decade, the Greenland ice sheet (GrIS) and its
surroundings have experienced record high surface temperatures (Mote,
2007; Box et al., 2010), ice sheet melt extent (Fettweis et al., 2011)
and record-low summer sea-ice extent (Nghiem et al., 2007). Using three
independent data sets, we derive, for the first time, consistent
ice-mass trends and temporal variations within seven major drainage
basins from gravity fields from the Gravity Recovery and Climate
Experiment (GRACE; Tapley et al., 2004), surface-ice velocities from
Inteferometric Synthetic Aperture Radar (InSAR; Rignot and Kanagaratnam,
2006) together with output of the regional atmospheric climate modelling
(RACMO2/GR; Ettema et al., 2009), and surface-elevation changes from the
Ice, cloud and land elevation satellite (ICESat; Sørensen et al.,
2011). We show that changing ice discharge (D), surface melting and
subsequent run-off (M/R) and precipitation (P) all contribute, in a
complex and regionally variable interplay, to the increasingly negative
mass balance of the GrIS observed within the last decade. Interannual
variability in P along the northwest and west coasts of the GrIS largely
explains the apparent regional mass loss increase during
2002-2010, and obscures increasing M/R and D since the 1990s. In
winter 2002/2003 and 2008/2009, accumulation anomalies in the east and
southeast temporarily outweighed the losses by M/R and D that prevailed
during 2003-2008, and after summer 2010. Overall, for all basins
of the GrIS, the decadal variability of anomalies in P, M/R and D
between 1958 and 2010 (w.r.t. 1961-1990) was significantly
exceeded by the regional trends observed during the GRACE period
(2002-2011).
Original language | English |
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Journal | Earth and Planetary Science Letters |
Volume | 333-334 |
Pages (from-to) | 293-303 |
ISSN | 0012-821X |
DOIs | |
Publication status | Published - 1 Jun 2012 |
ID: 40332599