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Title: NSF COLDEX 2022-23 Level 2 Basal Specularity Content Profiles
<p><b> Introduction </b> <br> The National Science Foundations Center for Oldest Ice Exploration (<a href="https://www.coldex.org">NSF COLDEX</a>) is a Science and Technology Center working to extend the record of atmospheric gases, temperature and ice sheet history to greater than 1 million years. As part of this effort, NSF COLDEX has been searching for a site for a continuous ice core extending through the mid-Pleistocene transition. Two seasons of airborne survey were conducted from South Pole Station across the southern flank of Dome A. </p> <p><b> 2022-2023 Field Season </b> <br> In the 2022-20223 field season (CXA1), and using a BT-67 Basler, NSF COLDEX conducted 13 full flights and one weather abort from South Pole Station toward the southern flank of Dome C; as well as 1 survey flight toward Hercules Dome in support of the Hercules Dome Drilling project. Three test flights were conducted from McMurdo Station. Instrumentation included the <a href="https://doi.org/10.18738/T8/J38CO5">60 MHz MARFA ice penetrating radar </a> from the University of Texas Institute for Geophysics, a <a href="https://doi.org/10.1109/IGARSS53475.2024.10640448">UHF ice penetrating radar </a> from the Center for Remote Sensing and Integrated Systems; an GT-2 Gravimeter, and LD-90 laser altimeter and an G-823 Magnetometer. </p> <p><b> Basal specularity content </b> <br> These basal specularity content were derived from comparing 1D and 2D focused MARFA data (<a href="http://doi.org/10.1109/TGRS.2007.897416">Peters et al., 2007</a>). By comparing bed echo strengths for different focusing apertures, and accounting for the ranges and angles involved, we can derive the "specularity content" of the bed echo, a proxy for small scale bed roughness and a good indicator for subglacial water pressure in regions of distributed subglacial water (<a href="https://doi.org/10.1109/LGRS.2014.2337878">Schroeder et al., 2014, IEEE GRSL </a>, <a href="https://doi.org/10.1016/j.epsl.2019.115961">Dow et al., 2019, EPSL </a>) and smooth deforming bed material (<a href="http://doi.org/10.1002/2014GL061645">Schroeder et al., 2014, GRL</a>, <a href="http://dx.doi/org/10.1098/rsta.2014.0297">Young et al., 2016, PTRS</a>. Specularity data are inherently noisy, so these products have been smoothed with a 1 km filter.</p>  more » « less
Award ID(s):
2019719
PAR ID:
10608390
Author(s) / Creator(s):
; ; ; ; ; ; ;
Corporate Creator(s):
Publisher / Repository:
Texas Data Repository
Date Published:
Subject(s) / Keyword(s):
Earth and Environmental Sciences ice penetrating radar radioglaciology Antarctica
Format(s):
Medium: X Size: 218321; 231928; 721553; 177176; 47642; 235861; 246357; 1077959; 80961; 648506; 158677; 44775; 91114; 58854; 590819; 63463; 166930; 56733; 1500803; 295994; 67050; 183074; 345449; 291025; 852327; 289900; 117372; 366675; 444028; 639165; 160477; 833695; 459453; 246178; 652378; 1126435; 1019865; 1237006; 324971; 51687; 1437694; 41619; 225457; 182434; 211240; 1330151; 677331; 203483; 272822; 337108; 1249959; 691316; 51602; 203309; 250386; 145977; 244126; 18943; 202171; 1338527; 152514; 1467660; 192244; 54832; 290773; 51651; 1119101; 606193; 198355; 57283; 177371; 211853; 1492671; 574743; 91488; 46006; 203174; 1678992; 891732; 1195291; 374961; 221578; 509047; 576397; 223018; 57883; 1766796; 47946; 292581; 1197611; 576693; 1541164; 54343; 1052168; 576333; 584747; 579501; 549757 Other: text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; text/plain; image/png; image/png; image/png; image/png
Size(s):
218321 231928 721553 177176 47642 235861 246357 1077959 80961 648506 158677 44775 91114 58854 590819 63463 166930 56733 1500803 295994 67050 183074 345449 291025 852327 289900 117372 366675 444028 639165 160477 833695 459453 246178 652378 1126435 1019865 1237006 324971 51687 1437694 41619 225457 182434 211240 1330151 677331 203483 272822 337108 1249959 691316 51602 203309 250386 145977 244126 18943 202171 1338527 152514 1467660 192244 54832 290773 51651 1119101 606193 198355 57283 177371 211853 1492671 574743 91488 46006 203174 1678992 891732 1195291 374961 221578 509047 576397 223018 57883 1766796 47946 292581 1197611 576693 1541164 54343 1052168 576333 584747 579501 549757
Location:
Antarctica; Antarctica; (East Bound Longitude:159.5; North Bound Latitude:-76.5; South Bound Latitude:-90; West Bound Longitude:-109)
Right(s):
Creative Commons Zero v1.0 Universal
Sponsoring Org:
National Science Foundation
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    <p><b> Introduction </b> <br> The National Science Foundations Center for Oldest Ice Exploration (<a href="https://www.coldex.org">NSF COLDEX</a>) is a Science and Technology Center working to extend the record of atmospheric gases, temperature and ice sheet history to greater than 1 million years. As part of this effort, NSF COLDEX has been searching for a site for a continuous ice core extending through the mid-Pleistocene transition. Two seasons of airborne survey were conducted from South Pole Station across the southern flank of Dome A. </p> <p><b> 2023-2024 Field Season </b> <br> In the 2023-2024 field season (CXA2), and using a BT-67 Basler, NSF COLDEX conducted 17 flights from South Pole Station toward the southern flank of Dome C. Three test flights were conducted from McMurdo Station. Instrumentation included the <a href="https://doi.org/10.18738/T8/J38CO5">60 MHz MARFA ice penetrating radar </a> from the University of Texas Institute for Geophysics, a <a href="https://doi.org/10.1109/IGARSS53475.2024.10640448">UHF ice penetrating radar </a> from the Center for Remote Sensing and Integrated Systems; an GT-2 Gravimeter, and LD-90 laser altimeter and an G-823 Magnetometer. </p> <p><b> Basal specularity content </b> <br> These basal specularity content were derived from comparing 1D and 2D focused MARFA data (<a href="http://doi.org/10.1109/TGRS.2007.897416">Peters et al., 2007</a>). By comparing bed echo strengths for different focusing apertures, and accounting for the ranges and angles involved, we can derive the "specularity content" of the bed echo, a proxy for small scale bed roughness and a good indicator for subglacial water pressure in regions of distributed subglacial water (<a href="https://doi.org/10.1109/LGRS.2014.2337878">Schroeder et al., 2014, IEEE GRSL </a>, <a href="https://doi.org/10.1016/j.epsl.2019.115961">Dow et al., 2019, EPSL </a>) and smooth deforming bed material (<a href="http://doi.org/10.1002/2014GL061645">Schroeder et al., 2014, GRL</a>, <a href="http://dx.doi/org/10.1098/rsta.2014.0297">Young et al., 2016, PTRS</a>. Specularity data are inherently noisy, so these products have been smoothed with a 1 km filter.</p> 
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