Publication Date:
2013-10-04
Description:
[1] Many challenges remain for estimating the Antarctic ice sheet surface mass balance (SMB), which represents a major uncertainty in predictions of future sea-level rise. Validating continental scale studies is hampered by the sparse distribution of in-situ data. Here we present a 26-year mean SMB of the Fimbul ice shelf in East Antarctica between 1983–2009, and recent interannual variability since 2010. We compare these data to results of large-scale SMB studies for similar time periods, obtained from regional atmospheric modeling and remote sensing. Our in-situ data include ground penetrating radar, firn cores and mass balance stakes, and provide information on both temporal and spatial scales. The 26-year mean SMB on the Fimbul ice shelf varies between 170 and 620 kg m -2 a -1 giving a regional average value of 310 ±70 kg m -2 a -1 . Our measurements indicate higher long-term accumulation over large parts of the ice shelf compared to the large-scale studies. We also show that the variability of the mean annual SMB, which can be up to 90 %, can be a dominant factor in short-term estimates. The results emphasize the importance of using a combination of ground based validation data, regional climate models and remote sensing over a relevant time period in order to achieve a reliable SMB for Antarctica.
Print ISSN:
0148-0227
Topics:
Geosciences
,
Physics
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