Interesting. Here's the abstract from the Joghin-Smith-Medley paper[1] in <i>Science</i> (the text of the paper itself is behind a paywall -- boo!):<p>> Resting atop a deep marine basin, the West Antarctic Ice Sheet has long been considered prone to instability. Using a numerical model, we investigate the sensitivity of Thwaites Glacier to ocean melt and whether unstable retreat is already underway. Our model reproduces observed losses when forced with ocean melt comparable to estimates. Simulated losses are moderate (<0.25 mm per year sea level) over the 21st Century, but generally increase thereafter. Except possibly for the lowest-melt scenario, the simulations indicate early-stage collapse has begun. Less certain is the timescale, with onset of rapid (> 1 mm per year of sea-level rise) collapse for the different simulations within the range of two to nine centuries.<p>[1] <a href="https://www.sciencemag.org/content/early/2014/05/12/science.1249055" rel="nofollow">https://www.sciencemag.org/content/early/2014/05/12/science....</a>