Deep inside the Greenland ice sheet are giant swirling plume-like structures. These have puzzled scientists for over a decade, but UiB-researchers now believe they have cracked the mystery by applying the same mathematics used to understand how continents drift apart.

“As wild as it is fascinating”

A new paper suggests the mysterious plumes are caused by thermal convection, which is a kind of slow churning movement inside the ice driven by vertical differences in temperature. Thermal convection is a process usually linked to the Earth’s fiery mantle. 

”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,” says Andreas Born, professor at the Bjerknes Centre for Climate Research and the Department of Earth Science at UiB. 

He has researched ice sheets in the Northern hemisphere for more than 15 years and is co-author of the new paper.

A freak of nature hidden under kilometres of ice

“Finding that thermal convection can happen within an ice sheet goes slightly against our intuition and expectations. Ice is at least a million times softer than the Earth’s mantle, though, so the physics just work out. It’s like an exciting freak of nature,” says glaciologist and first author Robert Law.

The paper was recently accepted in the journal The Cryosphere. The editors selected it as a ‘highlight paper’ due to its scientific significance.

“Our discovery could be key to reducing uncertainties in models of future ice sheet mass balance and sea-level rise,” says Born. 

Does not necessarily mean the ice will melt faster

Although the deep ice could be around ten times softer than commonly assumed, this does not necessarily mean it will melt faster.

“Improving our understanding of ice physics is a really major way to be more certain about the future,” says Law, “but on its own, softer ice does not necessarily mean that the ice will melt faster or that sea level rise will be higher. We need further studies to fully isolate that.”

Greenland is frequently in the headlines. Mining, geopolitics and climate risks are regular topics in the news. Law says their findings do not predict disaster on Greenland or elsewhere, but they do highlight how complex and dynamic Greenland is.

“Greenland and its nature is truly special. The ice sheet there is over one thousand years old, and it's the only ice sheet on Earth to have a culture and permanent population at its margins,” he says. “The more we learn about the hidden processes inside the ice, the better prepared we’ll be for the changes coming to coastlines around the world.”

 

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Robert Law
Photo: Private

“The Greenland ice sheet is a globally important store of fresh water. Our findings are helping to unravel one of the big mysteries about its internal structure”, says glaciologist Robert Law.

 

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Andreas Born
Photo: Gudrun Urd Sylte

“This study is bringing us closer to solving a long-standing scientific enigma”, says UiB-professor Andreas Born.

 

Reference: 

Law, R., Born, A., Voigt, P., MacGregor, J. A., & Guimond, C. M. (2025). Exploring the conditions conducive to convection within the Greenland Ice Sheet. The Cryosphere. DOI: https://doi.org/10.5194/tc-20-1071-2026 (external link)

About the study

  • Carried out by researchers at the University of Bergen (Department of Earth Sciences and the Bjerknes Centre for Climate Research), in collaboration with NASA Goddard Space Flight Center, the University of Oxford, and ETH Zurich.
  • The researchers investigated whether the large plume-like structures deep inside the Greenland ice sheet are formed by thermal convection, what this reveals about how soft the ice is, and how the ice sheet moves.
  • The findings show that plume-like structures are likely caused by thermal convection; a slow, churning movement inside the ice
  • The results indicate that deep ice in northern Greenland could be around ten times softer than commonly assumed.
  • Softer ice changes how the ice sheet moves, which helps researchers improve predictions of future sea level rise.