Science Source

Marine Ice Sheet Collapse Potentially Underway for the Thwaites Glacier Basin, West Antarctica

States that, resting atop a deep marine basin, the West Antarctic Ice Sheet has long been considered prone to instability
Investigates the sensitivity of Thwaites Glacier to ocean melt and whether unstable retreat is already underway, using a numerical model
The model reproduces observed losses when forced with ocean melt comparable to estimates
Finds that simulated losses are moderate (<0.25 mm per year sea level) over the 21st Century, but generally increase thereafter
Finds that, except possibly for the lowest-melt scenario, the simulations indicate early-stage collapse has begun
States that the timescale is less certain, 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