| Abstrakt: |
Geothermal heat plays a vital role in Antarctic ice sheet stability. The continental geothermal heat flow distribution depends on lithospheric composition and ongoing tectonism. Heat‐producing elements are unevenly enriched in the crust over deep time by various geological processes. The contribution of crustal heat production to geothermal heat flow is widely recognized; however, in Antarctica, crustal geology is largely hidden, and its complexity has frequently been excluded in thermal studies due to limited observations and oversimplified assumptions. Li and Aitken (2024), https://doi.org/10.1029/2023GL106201 take a significant step forward, focusing on Antarctic crustal radiogenic heat. Utilizing gravity inversion and rock composition data, they show that the crustal heterogeneity introduces considerable variability to heat flow. However, modeling crustal heat production proves challenging because it lacks distinct associations with geophysical observables and has a narrow spatial association. Robust quantification of geothermal heat production and heat flow must incorporate explicit aspects of geology. Plain Language Summary: Even moderate amounts of geothermal heat, or the natural warmth from the Earth's interior, can cause the base of Antarctica's ice sheets to melt or change how the ice behaves as it flows slowly toward the coast. Geothermal heat is not evenly spread within continents. Instead, it's influenced by how plate tectonics has affected the types of rocks present. While scientists agree that the Earth's crust is a major contributor to geothermal heat generation, studies in Antarctica have often left out how rock type differences might affect heat distribution. The study by Li and Aitken (2024), https://doi.org/10.1029/2023gl106201 looks more closely at how the Earth's crust beneath Antarctica varies and how that affects the heat impacting its ice sheets from below. In this commentary, we highlight that although heat production is difficult to model, their findings are important for understanding the natural influences on ice sheets as we observe and predict the impact of ongoing climate change. However, to provide robust estimates, a detailed geological understanding is required. Key Points: Antarctic ice sheet stability is highly dependent on the crustal contribution of radiogenic heat production to geothermal heat flowContrasts in crustal density may indicate upper crustal radiogenic heat production distributionsRobust geothermal models need to factor in heterogeneity at the scales of intrusions, metamorphic facies, and sedimentary units [ABSTRACT FROM AUTHOR] |
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