![]() Global map of solid Earth surface heat flow. in Special Report on the Ocean and Cryosphere in a Changing Climate (eds Pörtner, H.-O. Climate tipping points - too risky to bet against. Continental scale, high order, high spatial resolution, ice sheet modeling using the ice sheet system model (ISSM). Physical and chemical controls on habitats for life in the deep subsurface beneath continents and ice. Using ice-flow models to evaluate potential sites of million year-old ice in Antarctica. Solid Earth change and the evolution of the Antarctic Ice Sheet. Detailed review covering many aspects of heat flow and the thermal structure of the lithosphere. The Solid Earth: An Introduction to Global Geophysics (Cambridge Univ. In particular, the fast-changing Thwaites Glacier of West Antarctica, and the outlet glaciers of the Wilkes and Aurora Basins of East Antarctica, are locations of great concern.įowler, C. Geothermal heat flow is a boundary condition for modelling ice loss. The stable lithosphere of East Antarctica has relatively subtle geothermal heat flow anomalies, many of which are difficult to separate from model uncertainties and currently remain unresolved.įine-scale geothermal heat flow variations can be accounted for, through low and high bounds to possible geothermal heat flow in the form of uncertainty maps, to provide robust inputs to predictive modelling of Antarctic ice sheet evolution. High geothermal heat flow anomalies in West Antarctica are a consequence of multiple contributing sources, such as neotectonic rifting, volcanism and a mantle heat anomaly. Non-steady state processes and heat-producing elements in the upper crust contribute markedly to the spatial distribution of anomalously high geothermal heat flow values (>60%). GHF maps comprising central values with these fine-scale anomalies captured within uncertainty bounds can thus enable improved ensemble-based ice sheet model predictions of Antarctic ice loss.ĭifferences between geothermal heat flow maps for Antarctica that are derived using alternative approaches provide greater insight into its tectonic evolution than anomalies that are constrained from one model alone. Fine-scale anomalies owing to heat-producing elements and horizontal components of heat flow are important for regional modelling. The inferred variations across East Antarctica are more subtle (up to 66 mW m −2, 95th percentile), where slightly elevated values in some locations correspond to the influence of thinned lithosphere and tectonic units with concentrations of heat-producing elements. Combined influences cause especially high values in the vicinity of the Thwaites Glacier, a location critical for the accurate prediction of accelerated loss of Antarctic ice mass. The inferred GHF at continental scale for West Antarctica (up to 119 mW m −2, 95th percentile) points to numerous contributing influences, including non-steady state neotectonic processes. In this Review, we discuss variations in Antarctic GHF models based on geophysical methods and draw insights into tectonics and GHF model usage for ice sheet modelling. ![]() In Antarctica, GHF has further consequences in predicting the response of ice sheets to climate change. Geothermal heat flow (GHF) is an elusive physical property, yet it can reveal past and present plate tectonic processes.
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