Overview
- Peer‑reviewed modelling led by UC Irvine and NASA JPL now estimates Thwaites could add about 3 cm (1.2 in) to global sea level by 2100 and gives roughly a 60% probability the glacier will unpin from the Mouginot Ridge this century.
- The new models replace a narrow 'grounding line' with a multi‑kilometre grounding zone and identify a tidal‑pumping process that lets warm ocean water reach deep under grounded ice and accelerate basal melt.
- An independent British Antarctic Survey run of three ice‑sheet models found Thwaites would likely continue losing ice for about 150 years even in hypothetical scenarios with ocean‑driven melting switched off, indicating partial irreversibility on century scales.
- Direct measurements beneath Thwaites remain sparse, so researchers plan targeted in‑situ instrument deployments in 2028 to test the new grounding‑zone physics and narrow key uncertainties in projections.
- Thwaites already supplies about 4% of observed global sea‑level rise and has shed over 1,000 billion tonnes of ice since 2000; its full collapse would add about 65 cm to sea level and could trigger wider West Antarctic instability with much larger long‑term impacts, raising urgency for coastal planning and emissions cuts.