Skip to main content
×
×
Home

Power loss in dipping internal reflectors, imaged using ice-penetrating radar

  • Nicholas Holschuh (a1), Knut Christianson (a2) and Sridhar Anandakrishnan (a1)
Abstract

The geometry of ice-sheet internal layers is frequently interpreted as an indicator of present and past ice-sheet flow dynamics. One of the primary goals of radio-echo sounding is to accurately reproduce that layer geometry. Internal layers show a loss in reflection amplitude as a function of increasing dip angle. We posit that this energy loss occurs via several mechanisms: destructive interference in trace stacking, energy dispersion through synthetic aperture radar (SAR) processing and off-nadir ray path losses. Adjacent traces collected over a dipping horizon contain reflection arrivals which are not in phase. Stacking these traces results in destructive interference. When the phase shift between adjacent traces exceeds one-half wavelength, SAR processing, which otherwise coherently combines data from dipping reflectors, disperses the energy, reducing image quality further. Along with amplitude loss from destructive stacking and SAR dispersion, imaging reflectors from off-nadir angles results in additional travel time and thus additional englacial attenuation relative to horizontal reflectors at similar depths. When selecting radar frequency, spatial sample rate and stacking interval for a given survey, the geometry of the imaging target must be considered. Based on our analysis, we make survey design recommendations for these parameters.

  • View HTML
    • Send article to Kindle

      To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

      Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

      Find out more about the Kindle Personal Document Service.

      Power loss in dipping internal reflectors, imaged using ice-penetrating radar
      Available formats
      ×
      Send article to Dropbox

      To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

      Power loss in dipping internal reflectors, imaged using ice-penetrating radar
      Available formats
      ×
      Send article to Google Drive

      To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

      Power loss in dipping internal reflectors, imaged using ice-penetrating radar
      Available formats
      ×
Copyright
References
Hide All
Anandakrishnan, S, Catania, GA Alley, RB and Horgan, HJ (2007) Discovery of till deposition at the grounding line of Whillans Ice Stream. Science, 315(5820), 18351838 (doi: 10.1126/ science.1138393)
Arcone, SA Spikes, VB and Hamilton, GS (2005) Phase structure of radar stratigraphic horizons within Antarctic firn. Ann. Glaciol., 41, 1016 (doi: 10.3189/172756405781813267)
Bell, RE and 6 others (1998) Influence of subglacial geology on the onset of a West Antarctic ice stream from aerogeophysical observations. Nature, 394(6688), 5862 (doi: 10.1038/27883)
Bell, RE and 11 others (2011) Widespread persistent thickening of the East Antarctic Ice Sheet by freezing from the base. Science, 331(6024), 15921595 (doi: 10.1126/science.1200109)
Bentley, CR Lord, N and Lord, N (1998) Radar reflections reveal a wet bed beneath stagnant Ice Stream C and a frozen bed beneath ridge BC West Antarctica. J. Glaciol., 44(146), 149156
Bogorodsky, VV Bentley, CR and Gudmandsen, PE (1985) Radio-glaciology.. D Reidel, Dordrecht
Christianson, K, Jacobel, RW Horgan, HJ Anandakrishnan, S and Alley, RB (2012) Subglacial Lake Whillans – ice-penetrating radar and, GPS observations of a shallow active reservoir beneath a West Antarctic ice stream. Earth Planet. Sci. Lett., 331–332, 237–245 (doi: 10.1016/j.epsl.2012.03.013)
Christianson, K and 8 others (2013) Ice sheet grounding zone stabilization due to till compaction. Geophys. Res. Lett., 40(20), 54065411 (doi: 10.1002/2013GL057447)
Conway, H, Catania, G, Raymond, C, Scambos, T, Engelhardt, H and Engelhardt, H (2002) Switch of flow direction in an Antarctic ice stream. Nature, 419(6906), 465467 (doi: 10.1038/nature01081)
Dowdeswell, JA and Evans, S (2004) Investigations of the form and flow of ice sheets and glaciers using radio-echo sounding. Rep. Progr. Phys., 67(10), 18211861 (doi: 10.1088/0034-4885/67/ 10/R03)
Drews, R and 7 others (2009) Layer disturbances and the radio-echo free zone in ice sheets. Cryosphere, 3(2), 195203 (doi: 10.5194/tcd-3-307-2009)
Gades, AM Raymond, CF Conway, H and Jacobel, RW (2000) Bed properties of Siple Dome and adjacent ice streams, West Antarctica, inferred from radio-echo sounding measurements. J. Glaciol., 46(152), 8894 (doi: 10.3189/ 172756500781833467)
Jacobel, RW Gades, AM Gottschling, DL Hodge, SM and Wright, DL (1993) Interpretation of radar-detected internal layer folding in West Antarctic ice streams. J. Glaciol., 39(133), 528537
Jacobel, RW Welch, BC Osterhouse, D, Pettersson, R and MacGregor, JA (2009) Spatial variation of radar-derived basal conditions on Kamb Ice Stream, West Antarctica. Ann. Glaciol., 50(51), 1016 (doi: 10.3189/172756409789097504)
Jacobel, RW Lapo, KE Stamp, JR Youngblood, BW Welch, BC and Bamber, JL (2010) A comparison of basal reflectivity and ice velocity in East Antarctica. Cryosphere, 4(4), 447452 (doi: 10.5194/tc-4-447-2010)
Karlsson, NB Rippin, DM Vaughan, DG and Corr, HFJ (2009) The internal layering of Pine Island Glacier, West Antarctica, from airborne radar-sounding data. Ann. Glaciol., 50(51), 141146
Karlsson, NB Rippin, DM Bingham, RG and Vaughan, DG (2012) A ‘continuity-index’ for assessing ice-sheet dynamics from radar-sounded internal layers. Earth Planet. Sci. Lett., 335–336, 88–94 (doi: 10.1016/j.epsl.2012.04.034)
Kovacs, A, Gow, AJ and Morey, RM (1995) The in-situ dielectric constant of polar firn revisited. Cold Reg. Sci. Technol., 23(3), 245256 (doi: 10.1016/0165-232X(94)00016-Q)
Le Brocq, AM and 10 others (2013) Evidence from ice shelves for channelized meltwater flow beneath the Antarctic Ice Sheet. Nature Geosci., 6(11), 945948 (doi: 10.1038/ngeo1977)
Legarsky, JJ Gogineni, P and Atkins, TL (2001) Focused synthetic-aperture radar processing of ice-sounder data collected over the Greenland ice sheet. IEEE Trans. Geosci. Remote Sens., 39(10), 21092117 (doi: 10.1109/36.957274)
MacGregor, JA Winebrenner, DP Conway, H, Matsuoka, K, Mayewski, PA and Clow, GD (2007) Modeling englacial radar attenuation at Siple Dome, West Antarctica, using ice chemistry and temperature data. J. Geophys. Res., 112(F3), (F03008) (doi: 10.1029/2006JF000717)
MacGregor, JA Anandakrishnan, S, Catania, GA and Winebrenner, DP (2011) The grounding zone of the Ross Ice Shelf, West Antarctica, from ice-penetrating radar. J. Glaciol., 57(205), 917928 (doi: 10.3189/002214311798043780)
MacGregor, JA Matsuoka, K, Waddington, ED Winebrenner, DP and Pattyn F (2012) Spatial variation of englacial radar attenuation: modeling approach and application to the Vostok flowline. J. Geophys. Res., 117(F3), (F03022) (doi: 10.1029/2011JF002327)
MacGregor, J and 7 others (2013) Weak bed control of the eastern shear margin of Thwaites Glacier. J. Glaciol., 59(217), 900912 (doi: 10.3189/2013JoG13J050)
Matsuoka, K, Morse, D and Raymond, CF (2010) Estimating englacial radar attenuation using depth profiles of the returned power, central West Antarctica. J. Geophys. Res., 115(F2), (F02012) (doi: 10.1029/2009JF001496)
Matsuoka, K, Pattyn, F, Callens, D and Callens, D (2012) Radar characterization of the basal interface across the grounding zone of an ice-rise promontory in East Antarctica. Ann. Glaciol., 53(60 Pt 1), (29–44) (doi: 10.3189/2012AoG60A106)
Murray, T, Corr, H, Forieri, A and Smith, AM (2008) Contrasts in hydrology between regions of basal deformation and sliding beneath Rutford Ice Stream, West Antarctica, mapped using radar and seismic data. Geophys. Res. Lett., 35(12), (L12504) (doi: 10.1029/2008GL033681)
Ng, F and Ng, F (2004) Fast-flow signature in the stagnated Kamb Ice Stream, West Antarctica. Geology, 32(6), 481484 (doi: 10.1130/G20317.1)
Oswald, GKA and Gogineni, SP (2008) Recovery of subglacial water extent from Greenland radar survey data. J. Glaciol., 54(184), 94106 (doi: 10.3189/002214308784409107)
Robin, GdeQ (1975) Velocity of radio waves in ice by means of a bore-hole interferometric technique. J. Glaciol., 15(73), 151159
Rodríguez-Morales, F and 17 others (2013) Advanced multi-frequency radar instrumentation for polar research. IEEE Trans. Geosci. Remote Sens., 52(5), 28242842 (doi: 10.1109/ TGRS.2013.2266415)
Shabtaie, S and Bentley, CR (1988) Ice-thickness map of the West Antarctic ice streams by radar sounding. Ann. Glaciol., 11, 126136
Sime, LC Hindmarsh, RCA and Corr, HFJ (2011) Automated processing to derive dip angles of englacial radar reflectors in ice sheets. J. Glaciol., 57(202), 260266 (doi: 10.3189/ 002214311796405870)
Vaughan, DG Corr, HFJ, Doake, CSM and Waddington, ED (1999) Distortion of isochronous layers in ice revealed by ground-penetrating radar. Nature, 398(6725), 323326 (doi: 10.1038/ 18653)
Vaughan, DG and 8 others (2012) Subglacial melt channels and fracture in the floating part of Pine Island Glacier, Antarctica. J. Geophys. Res., 117(F3), (F03012) (doi: 10.1029/2012JF002360)
Welch, BC and Jacobel, RW (2003) Analysis of deep-penetrating radar surveys of West Antarctica, US-ITASE 2001. Geophys. Res. Lett., 30(8), (1444) (doi: 10.1029/2003GL017210)
Welch, BC Jacobel, RW and Arcone, SA (2009) First results from radar profiles collected along the US-ITASE traverse from Taylor Dome to South Pole (2006–2008). Ann. Glaciol., 50(51), 3541 (doi: 10.3189/172756409789097496)
Woodward, J and Burke, MJ (2007) Applications of ground-penetrating radar to glacial and frozen materials. J. Environ. Eng. Geophys., 12(1), 6985 (doi: 10.2113/JEEG12.1.69)
Yilmaz, Ö and Doherty, SM (2001) Seismic data analysis: processing, inversion and interpretation of seismic data: vol. 1.. Society of Exploration Geophysicists, Tulsa, OK
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Annals of Glaciology
  • ISSN: 0260-3055
  • EISSN: 1727-5644
  • URL: /core/journals/annals-of-glaciology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed