Louise Sime, The Guardian - Antarctica has 80 metres of potential sea-level rise. We don’t expect all of that, but it is harder to know exactly what is happening. Much of Antarctica is below sea level and affected by the ocean, which means it is less stable and harder to observe. We also know there are parts of Antarctica where warm water is encroaching on to unstable shelves and we know that ice could retreat in some of the sloping basins – for example in East Antarctica and Wilkes Land. We don’t know where that tipping point is, but if we hit it, there will be an irreversible retreat of the West Antarctic sheet....
We know that ice shelves can collapse in a matter of weeks or months.
On a bigger scale, evidence from the past suggests West Antarctica is unlikely to catastrophically lose all its ice in tens of years. It could unfold over hundreds or even thousands of years, but once you cross the tipping point and initiate that process, it is possible that we’d immediately see a substantial acceleration and jumps in sea level. We need more study.
... Some studies have suggested we may have passed tipping points, so the loss of the West Antarctic ice sheet may now be inevitable because of the warming of the oceans. However, this is far from clear. Tipping points definitely exist and we may already have passed some of the minor ones, but there’s also a good chance, in my view, that we haven’t yet crossed the major ones in Antarctica.
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