Mapping Of Debris Covered Ice Masses; Transantarctic Mountains, Antarctica
Global climate change threatens glacial ice, which contains vital information on paleoclimate, paleo-atmosphere, and ancient organisms due to rising temperatures and CO2 levels (IPCC, 2014). Throughout the Transantarctic Mountain Range, a minimal number of buried ice masses have been previously disc...
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UND Scholarly Commons
2021
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| Online Access: | https://commons.und.edu/theses/4188 https://commons.und.edu/cgi/viewcontent.cgi?article=5189&context=theses |
| Summary: | Global climate change threatens glacial ice, which contains vital information on paleoclimate, paleo-atmosphere, and ancient organisms due to rising temperatures and CO2 levels (IPCC, 2014). Throughout the Transantarctic Mountain Range, a minimal number of buried ice masses have been previously discovered which have the potential to contain ice that exceed the ages of most glaciers on Earth. These ice masses are buried under < 1 meter of till, which thermally shields them and limits sublimation, thus preserving the ice. An example of such buried ice mass is found in Ong Valley, Antarctica where a sublimation till completely covers the ice and is dated at > 1.1 Ma years old, consequently making it one of the oldest known ice masses on Earth.In addition to two published locations, no systematic effort has been made to map such ice masses in Antarctica. This research is motivated by the potential trove of paleoproxies harbored in these ancient ice masses. We used remotely sensed imagery (World View) to identify locations for these buried ice masses. The imagery consists of spectral bands in the blue, red, and green spectrum with sub-meter spatial resolution. The visual detection of landforms associated with buried ice masses combined with digital elevation models allows us to uniquely identify potential buried ice sites. To develop and refine our techniques, we used Ong Valley, Antarctica for ground-truthing. Over 8,000 images, covering an area of approximately 3.4 million km2, underwent analysis, providing 24 probable ancient ice masses. Out of these 24 sites, 8 were found to have the greatest potential for containing older ice due to experiencing more than one previous advancement of the Antarctic Ice Sheet. These sites are potential areas for future field-work to confirm the existence of ancient ice, and to extend the glacial paleoclimate archive further back in time, to increase our understanding of ice-sheet fluctuations, and to aid in future climate predictions. |
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