The facts
Mattia Poinelli and colleagues calibrated an ice-sheet model against nearly three decades of observed retreat, thinning and acceleration. [1]
The model reproduced those observations only when it included actively melting grounding zones two to five kilometres wide, accounting for seawater intrusions beneath the ice. [1]
The reported doubling concerns Thwaites' contribution, rather than all global sea-level rise. It is a model projection, not an observation that the glacier has already collapsed. [1][2]
The paper is Nature Communications 17, 10364, DOI 10.1038/s41467-026-77976-1. Grist independently reported its implications on 26 October. [1][2]
Still unconfirmed
- Actual future loss depends on glacier dynamics and ocean and climate conditions; the projection is not a guaranteed outcome.
Sources
References support the numbered facts above. Source checks: 29 Oct 2026, 07:46 UTC.
The paper's original abstract and figure captions were checked through PubMed, alongside Grist's independent reporting. Full Nature/PMC text was unavailable.
- Sea-level contribution from Thwaites Glacier doubles in an observation-constrained ice-sheet model
Poinelli and colleagues / Nature Communications, via PubMed · Primary source · 12 Oct 2026
- Thwaites faces runaway climate disaster, new studies show
Grist · Reporting · 26 Oct 2026
Sachi Kitajima Mulkey's reporting discusses multiple studies; only the October model is covered here.