Greenland ice sheet climate disequilibrium and committed sea-level rise
Box, J.E.; Hubbard, A.; Bahr, D.B.; Colgan, W.T.; Fettweis, X.; Mankoff, K.D.; Wehrlé, A.; Noël, B.; van den Broeke, M.R.; Wouters, B.; Björk, A.A.; Fausto, R.S. (2022). Greenland ice sheet climate disequilibrium and committed sea-level rise. Nat. Clim. Chang. 12(9): 808-813. https://dx.doi.org/10.1038/s41558-022-01441-2 In: Nature Climate Change. Nature Publishing Group: London. ISSN 1758-678X; e-ISSN 1758-6798, more |   |
| Authors | | Top | - Box, J.E.
- Hubbard, A.
- Bahr, D.B.
- Colgan, W.T.
| - Fettweis, X., more
- Mankoff, K.D.
- Wehrlé, A.
- Noël, B.
| - van den Broeke, M.R.
- Wouters, B.
- Björk, A.A.
- Fausto, R.S.
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| Abstract | Ice loss from the Greenland ice sheet is one of the largest sources of contemporary sea-level rise (SLR). While process-based models place timescales on Greenland’s deglaciation, their confidence is obscured by model shortcomings including imprecise atmospheric and oceanic couplings. Here, we present a complementary approach resolving ice sheet disequilibrium with climate constrained by satellite-derived bare-ice extent, tidewater sector ice flow discharge and surface mass balance data. We find that Greenland ice imbalance with the recent (2000–2019) climate commits at least 274 ± 68 mm SLR from 59 ± 15 × 103 km2 ice retreat, equivalent to 3.3 ± 0.9% volume loss, regardless of twenty-first-century climate pathways. This is a result of increasing mass turnover from precipitation, ice flow discharge and meltwater run-off. The high-melt year of 2012 applied in perpetuity yields an ice loss commitment of 782 ± 135 mm SLR, serving as an ominous prognosis for Greenland’s trajectory through a twenty-first century of warming. |
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