The Unexpected Internal Heat of Greenland’s Ice
For decades, climate models have treated the Greenland ice sheet as a largely static, albeit massive, block of frozen water. But a growing body of evidence suggests this simplification overlooks crucial internal dynamics. New research, published in The Cryosphere in 2026 by a team led by Robert Law of the University of Bergen in Norway, reveals that the ice sheet isn’t simply melting from the surface down – it’s experiencing convection, a process more commonly associated with the Earth’s mantle. This isn’t a prediction of imminent, accelerated melting, but a fundamental shift in our understanding of how this critical ice reservoir behaves, and therefore, how accurately we can forecast future sea level rise.
The discovery stems from puzzling features first identified in 2014 using ice-penetrating radar. These radar surveys, which map internal layers of ice based on how radio waves reflect off them, revealed large, upward-buckling structures deep within the northern Greenland ice sheet. These weren’t tied to the shape of the bedrock below, immediately ruling out simple geological explanations. Initial theories focused on the role of meltwater refreezing at the base of the ice or the movement of particularly slippery ice patches, but none fully accounted for the scale and shape of the observed anomalies. What Law and his team have now demonstrated, through sophisticated computer modeling, is that these structures bear a striking resemblance to thermal convection – the same process that drives the slow churning of molten rock within the Earth. “Finding that thermal convection can happen within an ice sheet goes slightly against our intuition and expectations,” explains Law, but “the physics just work out.”
Reporting from ScienceAlert informs this analysis.
The team’s approach was innovative in its methodology. Rather than developing a new model from scratch, they adapted a “geodynamics modeling package” – software typically used to simulate convection in the Earth’s mantle – to model a 2.5-kilometer-thick slab of ice. By adjusting variables like snowfall rate, ice thickness, and the ice’s softness, they found that under specific conditions, plume-like upwellings began to form within the model. These upwellings, rising columns of warmer, softer ice, folded the overlying layers into patterns that closely matched the radar images. Crucially, the model indicated that these plumes only formed when the ice near the base was significantly warmer and softer than previously assumed. This suggests that the base of the Greenland ice sheet may be far more pliable than standard models account for. The heat source driving this convection isn’t external; it’s geothermal heat emanating from the Earth itself – a tiny but persistent flow generated by radioactive decay and residual heat from the planet’s formation.
It’s important to clarify what this research doesn’t claim. Headlines proclaiming a “boiling” ice sheet are sensationalist. The ice isn’t slushy, and the convection occurs over timescales of thousands of years, not days or months. Furthermore, the study doesn’t automatically translate to faster melting. As Andreas Born, a climatologist at the University of Bergen, points out, “We typically think of ice as a solid material, so the discovery that parts of the Greenland ice sheet actually undergo thermal convection, resembling a boiling pot of pasta, is as wild as it is fascinating.” However, the implications for our understanding of ice sheet dynamics are profound. Previous models, built on the assumption of a relatively static ice mass, may be underestimating the rate at which heat is transferred within the ice sheet, and therefore, the potential for basal melting – melting from below.
Limitations to consider include the simplified nature of the model. The team used a single, two-dimensional slice of the ice sheet, and the real Greenland ice sheet is, of course, far more complex. The model also relies on assumptions about the ice’s properties, particularly its softness, which are based on limited observational data. More detailed radar surveys and direct measurements of ice temperature and viscosity at the base of the ice sheet are needed to validate the model’s findings. The study also doesn’t address the potential impact of changing ocean currents on basal melting, a factor known to significantly influence ice sheet stability.
The next crucial research step is to refine these models with more comprehensive data and to investigate how convection interacts with other processes, such as water drainage and surface melt. Specifically, scientists need to determine how widespread this convective activity is across the Greenland ice sheet and whether it’s accelerating in response to rising global temperatures. The question now isn’t simply if the Greenland ice sheet will melt, but how it will melt, and understanding the hidden processes within the ice is paramount to accurately predicting the future impact on coastlines worldwide. Will future radar surveys reveal similar convective patterns in other ice sheets, like those in Antarctica? That’s a question researchers are actively pursuing, and the answer could reshape our understanding of global sea level rise for generations to come.
