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Potential sea-level rise from Antarctic ice-sheet instability constrained by observations [Stoat]
Catherine Ritz, Tamsin L. Edwards, Gaël Durand, Antony J. Payne, Vincent Peyaud & Richard C. A. Hindmarsh; Nature (2015) doi:10.1038/nature16147. And somewhat following on from Joan Crawford has risen from the grave! only its sane, well-crafted, and most important of all not only publishable but actually published. From the abstract:
Large parts of the Antarctic ice sheet lying on bedrock below sea level may be vulnerable to marine-ice-sheet instability… may be underway throughout the Amundsen Sea embayment… Physically plausible projections are challenging: numerical models with sufficient spatial resolution to simulate grounding-line processes have been too computationally expensive… and lower-resolution model projections rely on parameterizations that are only loosely constrained by present day changes. Here we project that the Antarctic ice sheet will contribute up to 30 cm sea-level equivalent by 2100 and 72 cm by 2200 (95% quantiles) where the ASE dominates. Our process-based, statistical approach… The dependence of sliding on basal friction is a key unknown: nonlinear relationships favour higher contributions. Results are conditional on assessments of MISI risk on the basis of projected triggers under the climate scenario A1B (ref. 9), although sensitivity to these is limited by theoretical and topographical constraints on the rate and extent of ice loss. We find that contributions are restricted by a combination of these constraints, calibration with success in simulating observed ASE losses, and low assessed risk in some basins. Our assessment suggests that upper-bound estimates from low-resolution models and physical arguments (up to a metre by 2100 and around one and a half by 2200) are implausible under current understanding of physical mechanisms and potential triggers.
Its saying that modelling is too hard, so lets try a more statistical approach; and if they do that, they get numbers that are, they believe, constrained to be smaller than some of the wilder estimates people have been flinging around.
The pic is the trees at Chatsworth edge.
Refs
* Batter my heart, three-person’d God
Source: http://scienceblogs.com/stoat/2015/11/18/potential-sea-level-rise-from-antarctic-ice-sheet-instability-constrained-by-observations/
Only probable, and NASA says its getting thicker, Somehow I believe increasing ice thickness and an ever expanding South polar ice cap means an Ice Age commeth, at least in the Southern Hemisphere.