Ice mass loss continues at a high rate among the large glacier tributaries of the Larsen B Ice
Shelf following its disintegration in 2002. We evaluate recent mass loss by mapping elevation
changes between 2006 and 2010/11 using differencing of digital elevation models (DEMs).
The measurement accuracy of these elevation changes is confirmed by a 'null test', subtracting
DEMs acquired within a few weeks. The overall 2006-2010/11 mass loss rate (9.0±2.1 Gt/yr) is
similar to the 2001/02-2006 rate (8.8±1.6 Gt/yr), derived using DEM differencing and laser altimetry.
This unchanged overall loss masks a varying pattern of thinning and ice loss for individual glacier basins.
On Crane Glacier, the thinning pulse, initially greatest near the calving front, is now broadening
and migrating upstream. The largest losses are now observed for the Hektoria/Green glacier basin,
having increased by 33% since 2006. Our method has enabled us to resolve large residual uncertainties
in the Larsen B sector and confirm its state of ongoing rapid mass loss.
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