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3/ We analyzed 18 major Antarctic ice drainage basins using the ice-sheet model #PISM, gradually increasing global mean temperature to map their long-term response. Result: different regions respond very differently to warming.

4/ Some ice basins show relatively gradual ice loss as temperatures rise. Others exhibit tipping behavior: beyond a critical warming level, ice loss accelerates disproportionately and can become irreversible over centuries to millennia.

5/ West Antarctic basins (inc Thwaites & Pine Island) have the lowest thresholds. At today’s ~1.3C, parts of these regions may already be committed to long-term loss. Important: crossing a tipping point ≠ immediate collapse. Ice sheets respond slowly—but once triggered, the process is hard to stop.

6/ But it’s not just West Antarctica. Our results indicate that major ice basins in East Antarctica (e.g. Wilkes) become increasingly vulnerable at sustained warming of ~2–5C. East Antarctica holds much more ice — enough to raise sea levels 10X more than West Antarctica.

7/ Another key insight: the ice drainage basins interact. Ice loss in one region can lead to dynamic feedbacks in neighboring regions, increasing the risk of cascading responses.

8/ The Antarctic Ice Sheet contains enough ice to raise global sea levels by >58 meters if melted entirely. We are NOT talking about this happening soon. But several individual basins have the potential to contribute meters of long-term sea-level rise if their thresholds are crossed.

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9/ The Antarctic Ice Sheet took millions of years to form. Yet, with continued emissions, we may commit parts of it to irreversible long-term loss — potentially within decades. Near-term emissions determine how many thresholds we may cross in the long-term.

10/ Our analysis identifies which regions of the ice sheet require closest monitoring and where the largest long-term risks lie. The lesson is clear: reducing GHG emissions rapidly remains imperative to limit further destabilization of Antarctic ice basins and future irreversible sea-level rise.