In:
Annals of Glaciology, International Glaciological Society, Vol. 56, No. 70 ( 2015), p. 105-117
Abstract:
We revisit the input–output mass budget of the high-elevation region of the Greenland ice sheet evaluated by the Program for Arctic Regional Climate Assessment (PARCA). Our revised reference period (1961–90) mass balance of 54±48 Gt a –1 is substantially greater than the 0±21 Gt a –1 assessed by PARCA, but consistent with a recent, fully independent, input–output estimate of high-elevation mass balance (41±61 Gt a –1 ). Together these estimates infer a reference period high-elevation specific mass balance of 4.8±5.4 cm w.e. a –1 . The probability density function (PDF) associated with this combined input–output estimate infers an 81% likelihood of high-elevation specific mass balance being positive ( 〉 0 cm w.e. a –1 ) during the reference period, and a 70% likelihood that specific balance was 〉 2 cm w.e. a –1 . Given that reference period accumulation is characteristic of centurial and millennial means, and that in situ mass-balance observations exhibit a dependence on surface slope rather than surface mass balance, we suggest that millennial-scale ice dynamics are the primary driver of subtle reference period high-elevation mass gain. Failure to acknowledge subtle reference period dynamic mass gain can result in underestimating recent dynamic mass loss by ~17%, and recent total Greenland mass loss by ~7%.
Type of Medium:
Online Resource
ISSN:
0260-3055
,
1727-5644
DOI:
10.3189/2015AoG70A967
Language:
English
Publisher:
International Glaciological Society
Publication Date:
2015
detail.hit.zdb_id:
2122400-6
SSG:
14
