Sea-level contribution from Thwaites Glacier doubles in an observation-constrained ice-sheet model

Thwaites Glacier is a major contributor to Antarctic mass loss and a key source of uncertainty in future sea-level rise.

By Poinelli, Rignot, Seroussi +3Nature CommunicationsOct 12, 2026

Score████░░░░░░4.3

VerdictWorth a reader's time today.

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Abstract

Abstract Thwaites Glacier is a major contributor to Antarctic mass loss and a key source of uncertainty in future sea-level rise. Ocean-driven melting at its grounding line drives rapid retreat, yet most models treat the transition between grounded and floating ice as a sharp boundary, neglecting kilometer-scale seawater intrusions that develop as the grounding line migrates and forms a grounding zone. Here, we show that actively-melting grounding zones are required to reproduce nearly three decades of observed retreat, thinning, and acceleration of Thwaites Glacier in a calibrated ice-sheet model, with successful reconstruction occurring only when grounding zones are represented as 2-5 km wide regions. Extending this model forward, we show that grounding-zone processes govern glacier’s detachment from stabilizing seafloor ridges, enabling unpinning as early as 2038 and producing up to 30 ± 6 mm of global mean sea-level rise by 2100 - approximately double previous projections even without additional climate warming.

Mattia Poinelli, Eric J. Rignot, Helene L. Seroussi, Joshua Cuzzone, Tyler Pelle, Eric Larour

The editor's rubric

Heuristic review

Dimension	Level	Weight	What that level means
Leverage	███░░ 3	16%	A method or resource many groups across the field will adopt within a year.
Magnitude	██░░░ 2	20%	Solid incremental gain on a meaningful problem.
Evidence	███░░ 3	20%	Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.
Novelty	███░░ 3	10%	A genuinely new approach to an open problem.
Trajectory	██░░░ 2	14%	Some room to improve with obvious engineering.
Stakes	███░░ 3	20%	Meaningful benefit to many people within a few years.

Editor’s rationale

Heuristic triage from title and abstract text only, not a reading of the paper. Cues found: method (we report); novelty (open problem); verification (error bars); scale (scalable); stakes (global scale, climate).

How the score was computed

rank-2026-10-07

Score████░░░░░░4.3

Score = 10 × (75% × adjusted merit / 10 + 15% × attention + 10% × freshness)

Merit: 5.3 / 10; Weighted rubric, evidence-gated.
Adjusted merit: 4.5 / 10; Shrunk toward the desk prior by editor confidence (42%).
Attention: 0%; Citations, upvotes, points, mentions.
Freshness: 85%; Half-life decay since publication.

Citations0 (reference 15, via openalex, Oct 14, 2026, 07:30 UTC)

The record

Reviewed by heuristic-v6 on Oct 14, 2026, 07:29 UTC. Paper type: method.
Categories: Cryospheric studies and observations, Geology and Paleoclimatology Research, Polar Research and Ecology, Atmospheric Science, Earth and Planetary Sciences
BRIEF, No.1 in the Climate & Energy edition of October 14, 2026.