Greenland’s natural resources—critical minerals and clean energy potential, in particular—have evolved into a cornerstone for renewable energy transitions and sustainability efforts elsewhere in the world. Unraveling the intricacies of Greenland’s subsurface, where these resources reside but which remains relatively unknown, could facilitate efficient exploration and responsible management of these natural resources.
Recently, the European Union signed a memorandum of understanding with the government of Greenland to develop sustainable raw material value chains, aiming to secure a diversified and steady supply of critical minerals essential for the green transition. The collaboration encompasses economic integration, infrastructure development, skill building, and joint research to ensure the sustainable use of these resources.
Similarly, the United States is making efforts to invest in Greenland’s mining sector to boost the supply of materials needed for clean energy technologies. U.S. officials have engaged with Greenlandic authorities and potential investors, highlighting Greenland’s potential to become the next mining frontier.
As international interest grows, responsible exploration and development of Greenland’s resources are crucial to ensure environmental protections and benefits for local communities.
Both the European Union and the United States recognize the strategic importance of Greenland’s resources in meeting global demand for critical minerals vital for a sustainable future. As international interest grows, responsible exploration and development of Greenland’s resources are crucial to ensuring environmental protections and benefits for local communities.
Less obvious but equally important, our understanding of subsurface phenomena pivotally informs climate modeling and long-term forecasts of sea level rise, ocean currents, and climate change. The thermal structure deep beneath Greenland controls the geothermal energy release at the base of the ice sheet, directly influencing the rate at which the ice sheet melts. This melting not only contributes to rising sea levels but also alters the amount of fresh water entering the oceans, which affects currents and climate.
In March 2024, scientists from across Europe, the United States, and Canada who study Greenland’s lithosphere (comprising the crust and uppermost mantle) convened in Copenhagen for a landmark workshop. The purpose was to review the past and present state of knowledge about Greenland’s subsurface structure and dynamics in the context of climate change and resource exploration and to discuss collaborative steps to address outstanding scientific questions and challenges.
Everything’s Connected
How does Greenland’s lithosphere affect the climate above it? A rush of recent scientific studies has elucidated the impact of Greenland’s melting ice sheet on global ocean currents and climate patterns. This ice melting is heavily influenced by rising air temperatures and other conditions at the ice sheet surface, of course, but it is also closely linked to conditions beneath the ice, including geothermal heat flow and the mechanical properties of Earth’s interior.
The need for precise ice melting models and the corresponding imperative to grasp Greenland’s lithospheric structure, dynamics, and surface heat flow are becoming more critical.
This connection is easy to grasp when we consider how differences in lithospheric thickness influence a cascade of effects. For example, areas with thin lithosphere, such as the East African Rift, have elevated thermal gradients (i.e., the transition from subsurface to surface temperatures occurs over a shorter distance), leading to higher surface heat flow and mechanically weaker tectonic plates. In Greenland, high surface heat flow accelerates ice melting, and weaker sections of plate facilitate relatively rapid vertical movements of the surface as it rebounds in response to ice loss, a phenomenon known as glacial isostatic adjustment.
Against a backdrop of escalating concerns over the effects of climate change, the need for precise ice melting models and the corresponding imperative to grasp Greenland’s lithospheric structure, dynamics, and surface heat flow are becoming more critical.
Progress Toward a More Holistic Approach
The Copenhagen workshop focused on Greenland’s lithospheric structure and its connection to key natural resources and natural hazards while shedding light on the implications of subsurface dynamics for modeling of ice melting and climate. Participants presented, reviewed, and assessed a wealth of geoscientific data relevant to our understanding of Greenland’s subsurface composition, thermal structure, and dynamics from the top of the crust down to the deep upper mantle.
A major theme of the workshop was the reconciliation of disparate datasets and predictions regarding Greenland’s lithospheric structure. Ten years ago, conflicting models of important subsurface traits such as crustal density and lithospheric and crustal thickness stirred controversies and hindered consensus among researchers. For example, predictions of lithospheric thickness in different models differed by as much as 80%–120% in large portions of central and northern Greenland.
During the workshop, it became clear that at least part of the explanation for the model differences can be traced to the use of single-discipline or single–data type approaches (e.g., using only specific seismic data or gravity inversion data) to model the subsurface in a region that is poorly covered by land-based datasets. It is now well known in the geophysical community that many types of data, when considered on their own, have limited sensitivity to variations in properties like lithospheric thickness.
Therefore, when researchers reconstruct images of subsurface features using only a few observations from a single dataset, they must supplement these observations using modeling assumptions (e.g., about relationships between model parameters or maximum allowed variations in the model). These assumptions invariably add subjectivity and may result in different models of the same subsurface feature. By contrast, working with multiple datasets with complementary sensitivities tends to reduce ambiguity in models and in the images of the subsurface they produce.
Accordingly, a central focus of the workshop was to explore the opportunities and added value inherent in integrating new and diverse datasets (e.g., integrating gravity, seismic, and magnetic datasets) to construct more robust models, capitalizing on the different coverages and sensitivities offered by each dataset.
At the workshop, several groups showcased comprehensive models of Greenland’s lithosphere, each offering unique perspectives and nuances but collectively showing critical consistencies in fundamental features, such as patterns of lithospheric thickness, density anomalies, and temperature structure (Figure 1). This convergence marks a significant milestone in our understanding, indicating that past discrepancies are being ironed out and raising confidence in the validity and predictions of the models.
From Knowledge to Applications
With a clearer understanding of Greenland’s lithospheric architecture and thermal structure, scientists are better positioned to advise local governments and inform exploration efforts aimed at revealing its abundant natural resources.
This newfound confidence has key implications for exploration and management programs related to critical minerals, energy, and hazard mitigation. With a clearer understanding of Greenland’s lithospheric architecture and thermal structure, scientists are better positioned to advise local governments and inform exploration efforts aimed at revealing its abundant natural resources. From there, geothermal energy potential and critical mineral deposits could be targeted with greater precision, promoting more efficient and sustainable resource use and helping accelerate energy transitions.
Furthermore, with improved lithospheric models, glaciologists and scientists studying glacial isostatic adjustment have better constraints on heat flow at the base of the ice sheet, as well as on temperatures and compositions of the crust and mantle. With this knowledge, these researchers can refine model estimates of ice evolution, sea level change, and variations in land motion, gravity, and tectonic stress. These advances are vital for assessing the regional and global impacts of the response of the Greenland ice sheet to climate warming.
Charting a Way Forward
The workshop concluded with a resounding call for continued collaboration and interdisciplinary research to further refine understanding of Greenland’s natural systems. Indeed, plans are underway for future deployments of seismic instrumentation in critical regions by both U.S. and European research groups, as well as for multi-institution collaborative projects. In addition, the entire group of workshop attendees pledged to more closely integrate satellite and airborne datasets with seismic data, a commitment now being realized by workshop attendees.
These plans aim to leverage the newfound knowledge discussed at the March workshop in Copenhagen—and during a follow-up splinter meeting held in April at the European Geosciences Union General Assembly 2024—to address pressing scientific questions and challenges related to sustainable resource management, climate modeling, and resilience.
Of particular interest are new multidata methods and acquisition programs designed to better evaluate the thermal and lithological structure of the crust beneath retreating ice sheets. Evaluating such factors as the surface heat flux beneath central Greenland, mantle dynamics, and the rheological structure of the lithosphere is crucial for predicting relative sea level changes and the evolution of ice sheets. (A white paper discussing these sessions in more technical detail is currently being written.)
As Greenland’s significance in global discussions about natural resource use and climate change continues to grow, efforts like these serve as critical mechanisms for advancing scientific understanding, fostering international collaboration and engagement, and informing evidence-based decisionmaking.
Acknowledgments
We acknowledge the participants in the March 2024 workshop held at the headquarters of the Geological Survey of Denmark and Greenland, who include the following: John Hopper, Juan Carlos Afonso, Clint Conrad, Jörg Ebbing, Samantha Hansen, Judith Freienstein, Rene Forsberg, Biao Lu, Alexander Minakov, Derek Schutt, Rebekka Steffen, Kristoffer Szilas, Agnes Wansing, Zhirui Ray Wang, Bjørn Henning Heincke, Pierpaolo Guarnieri, Trine Dahl-Jensen, Thomas Funck, Carmen Gaina, Parviz Ajourlou, Sergei Lebedev, Glenn Milne, Fiona Darbyshire, Andrew Schaeffer, Giampiero Iaffaldano, Max Moorkamp, Glenn Jones, and Judith Bott.
Author Information
Juan C. Afonso (j.c.afonso@utwente.nl), Faculty of Geo-Information Science and Earth Observation, University of Twente, Enschede, Netherlands; Agnes Wansing, Institute of Geosciences, Kiel University, Kiel, Germany; Parviz Ajourlou, Department of Earth and Environmental Science, University of Ottawa, Ottawa, Ont., Canada; John Hopper, Department of Geophysics and Sedimentary Basins, Geological Survey of Denmark and Greenland, Copenhagen; and Jörg Ebbing, Institute of Geosciences, Kiel University, Kiel, Germany
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