First Study Links Human Activity to Antarctic Glacier Retreat

Scientists at King’s College London and the British Antarctic Survey have published the first study to directly attribute the retreat of a major Antarctic outlet glacier to human activity. The research, led by Dr. Alex Bradley and published in The Cryosphere, focuses on Pine Island Glacier, which drains a large portion of the West Antarctic Ice Sheet into the Amundsen Sea and is among the largest single contributors to global sea level rise. The study found that greenhouse gas emissions (ghg) increased the glacier’s retreat by approximately 18% to 20% since the 1940s, accounting for roughly 4 kilometers of its landward withdrawal by 2015.

Attribution science, which attempts to quantify the contribution of human-driven warming to specific climate events or changes, has become standard practice for heatwaves, extreme rainfall, and mountain glacier loss. Applying equivalent methods to Antarctic glaciers has been significantly more difficult because of the complexity of ice sheet dynamics, ocean circulation, and the longer timescales involved. This study represents the first successful application of that approach to a major Antarctic glacier.

What the Study Found and How

Geological records indicate that Pine Island Glacier began retreating rapidly in the 1940s, most likely due to increased intrusions of warm ocean water beneath its ice shelf. The study’s contribution is to quantify how much of that retreat was amplified by human-driven ocean warming, which the researchers identify as beginning to have a measurable effect in the 1960s.

The research team used a glacier model calibrated against observed changes in ice thickness and grounding-line position, comparing simulation results with and without human-driven global warming included. By 2015, models excluding human influence showed approximately 4 kilometers less grounding-line retreat than those including it. That 4-kilometer difference represents just under one-fifth of the glacier’s total observed retreat over the period. “Without sustained warming of the surrounding ocean since the mid-twentieth century, the glacier would not have retreated as far as it has,” Dr. Bradley said in a guest post for Carbon Brief describing the findings.

The Long-Term Outlook and Its Planning Implications

The study’s forward-looking projections are notable for their timescale. Models suggest Pine Island Glacier may briefly stabilize later this century as the grounding line encounters a ridge in the bedrock beneath it. That stabilization is likely temporary if warming continues. Human influence is projected to become the dominant driver of retreat again in the twenty-second century. “Ice sheets respond slowly,” Dr. Bradley said. “The impacts of today’s emissions will continue to shape Antarctic ice loss for centuries.”

For sustainability and corporate strategy teams, the study’s significance extends beyond the science itself. Attribution research of this type increasingly underpins regulatory disclosure frameworks, physical climate risk assessments, and investor due diligence processes. The ability to quantify the human contribution to specific physical climate outcomes, rather than describing them in probabilistic terms, strengthens the evidentiary basis for long-term climate risk modeling. As the study’s co-author Mira Adhikari of the British Antarctic Survey noted, the results add to growing evidence that human-driven climate change is likely affecting even the most remote regions of the planet, with changes in Antarctica carrying global consequences particularly for sea level rise.

The research does not produce a near-term sea level projection for planning purposes, and the authors are careful to distinguish between the historical attribution finding and forward-looking scenarios. What it does establish is that the mechanism connecting emissions to Antarctic ice loss is now quantifiable in ways it previously was not, which will inform both scientific modeling and the frameworks organizations use to assess long-term physical climate exposure.