Antarctic Geothermal Heat Flow Model: Aq1. (24th February 2021)

• Record Type: Journal Article
• Authors: Stål, Tobias; Reading, Anya M.; Halpin, Jacqueline A.; Whittaker, Joanne M.
• Is Part Of: Geochemistry, geophysics, geosystems. Volume 22:Number 2(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-02-24
• Subjects: Antarctica -- heat flow -- geothermal -- multivariate; Geochemistry -- Periodicals; Geophysics -- Periodicals; Earth sciences -- Periodicals; 550.5
• DOI: 10.1029/2020GC009428
• Languages: English
• ISSNs: 1525-2027

Abstract

Abstract: We present a refined map of geothermal heat flow for Antarctica, Aq1, based on multiple observables. The map is generated using a similarity detection approach by attributing observables from geophysics and geology to a large number of high‐quality heat flow values ( N = 5, 792) from other continents. Observables from global, continental, and regional datasets for Antarctica are used with a weighting function that allows the degree of similarity to increase with proximity and how similar the observables are. The similarity detection parameters are optimized through cross correlation. For each grid cell in Antarctica, a weighted average heat flow value and uncertainty metrics are calculated. The Aq1 model provides higher spatial resolution in comparison to previous results. High heat flow is shown in the Thwaites Glacier region, with local values over 150 mW m −2 . We also map elevated values over 80 mW m −2 in Palmer Land, Marie Byrd Land, Victoria Land and Queen Mary Land. Very low heat flow is shown in the interior of Wilkes Land and Coats Land, with values under 40 mW m −2 . We anticipate that the new geothermal heat flow map, Aq1, and its uncertainty bounds will find extended use in providing boundary conditions for ice sheet modeling and understanding the interactions between the cryosphere and solid Earth. The computational framework and open architecture allow for the model to be reproduced, adapted and updated with additional data, or model subsets to be output at higher resolution for regional studies. Plain Language Summary: We present a new map that shows how the heat from the deep Earth varies from place to place in Antarctica. The map shows where raised heat flow values beneath ice sheets need to be included to better predict how ice sheets will respond to the Earth's warming climate. Areas with volcanoes have high geothermal heat flow. Other medium to high heat flow locations are often hard to identify, especially as it is too difficult or expensive to measure the heat directly in the harsh and sensitive Antarctic environment. To overcome this challenge, we use a technique with computer‐aided match between the best data we can compile for Antarctica and corresponding data and heat flow values from other continents. Key Points: A new heat flow map of Antarctica suitable for solid Earth and interdisciplinary studies is presented Multiple observables are combined in a similarity approach to link global data compilations A reproducible, adaptable workflow with uncertainty metrics is provided