Skip to main content Accessibility help

Early melt season velocity fields of Langjökull and Hofsjökull, central Iceland

  • Brent Minchew (a1), Mark Simons (a1), Scott Hensley (a2), Helgi Björnsson (a3) and Finnur Pálsson (a3)...

We infer the horizontal velocity fields of the ice caps Langjökull and Hofsjökull, central Iceland, using repeat-pass interferometric synthetic aperture radar (InSAR). NASA’s uninhabited aerial vehicle synthetic aperture radar (UAVSAR) acquired airborne InSAR data from multiple vantage points during the early melt season in June 2012. We develop a Bayesian approach for inferring three-dimensional velocity fields from multiple InSAR acquisitions. The horizontal components generally agree with available GPS measurements wherever ice motion is well constrained by InSAR observations. We provide evidence that changes in volumetric moisture content near the glacier surface induce phase offsets that obfuscate the vertical component of the surface velocity fields, an effect that could manifest itself on any glacier that experiences surface melt. Spatial patterns in the InSAR-derived horizontal speeds are broadly consistent with the results of a simple viscous flow model, and the directionality of the InSAR-derived horizontal flow field is nearly everywhere consistent with the ice surface gradient. Significant differences between the InSAR-derived horizontal speed and the speed predicted by the viscous flow model suggest that basal slip accounts for more than half the observed outlet glacier flow.

  • View HTML
    • Send article to Kindle

      To send this article to your Kindle, first ensure 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 or variations. ‘’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘’ 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.

      Early melt season velocity fields of Langjökull and Hofsjökull, central Iceland
      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.

      Early melt season velocity fields of Langjökull and Hofsjökull, central Iceland
      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.

      Early melt season velocity fields of Langjökull and Hofsjökull, central Iceland
      Available formats
Corresponding author
Correspondence: Brent Minchew <>
Hide All
Bartholomaus, TC, Anderson, RS and Anderson, SP (2011) Growth and collapse of the distributed subglacial hydrologic system of Kennicott Glacier, Alaska, USA, and its effects on basal motion. J. Glaciol., 57(206), 9851002 (doi: 10.3189/002214311798843269)
Bartholomew, I, Nienow, P, Mair, D, Hubbard, A, King, MA and Sole, A (2010) Seasonal evolution of subglacial drainage and acceleration in a Greenland outlet glacier. Nature Geosci., 3(6), 408411 (doi: 10.1038/ngeo863)
Bertiger, W and 6 others (2010) Single receiver phase ambiguity resolution with GPS data. J. Geod., 84(5), 327337 (doi: 10.1007/s00190-010-0371-9)
Björnsson, H (1986) Surface and bedrock topography of ice caps in Iceland, mapped by radio echo-sounding. Ann. Glaciol., 8, 1118
Björnsson, H (1988) Hydrology of ice caps in volcanic regions. Vísindafélag Ísl. Rit. 45
Björnsson, H and Pálsson, F (2008) Icelandic glaciers. Jökull, 58, 365386
Björnsson, H, Pálsson, F, Sigurðsson, O and Flowers, GE (2003) Surges of glaciers in Iceland. Ann. Glaciol., 36, 8290 (doi: 10.3189/172756403781816365)
Boulton, GS (1979) Processes of glacier erosion on different substrata. J. Glaciol., 23(89), 1538
Chen, CW and Zebker, HA (2000) Network approaches to two-dimensional phase unwrapping: intractability and two new algorithms. J. Opt. Soc. Am., Ser. A, 17(3), 401414 (doi: 10.1364/JOSAA.17.000401)
Chen, CW and Zebker, HA (2001) Two-dimensional phase unwrapping with use of statistical models for cost functions in nonlinear optimization. J. Opt. Soc. Am., Ser. A, 18(2), 338351 (doi: 10.1364/JOSAA.18.000338)
Chen, CW and Zebker, HA (2002) Phase unwrapping for large SAR interferograms: statistical segmentation and generalized network models. IEEE Trans. Geosci. Remote Sens., 40(8), 17091719 (doi: 10.1109/TGRS.2002.802453)
Cuffey, KM and Paterson, WSB (2010) The physics of glaciers, 4th edn. Butterworth-Heinemann, Oxford
Duputel, Z, Agram, PS, Simons, M, Minson, SE and Beck, JL (2014) Accounting for prediction uncertainty when inferring subsurface fault slip. Geophys. J. Int., 197(1), 464482 (doi: 10.1093/gji/ggt517)
Emardson, TR, Simons, M and Webb, FH (2003) Neutral atmospheric delay in interferometric synthetic aperture radar applications: statistical description and mitigation. J. Geophys. Res., 108(B5), 2231 (doi: 10.1029/2002JB001781)
Engelhardt, H and Kamb, B (1998) Basal sliding of Ice Stream B, West Antarctica. J. Glaciol., 44(147), 223230
Glen, JW (1955) The creep of polycrystalline ice. Proc. R. Soc. London, Ser. A, 228(1175), 519538 (doi: 10.1098/rspa.1955.0066)
Gourmelen, N, Kim, SW, Shepherd, A, Park, JW, Sundal, AV and Björnsson, H (2011) Ice velocity determined using conventional and multiple-aperture InSAR. Earth Planet. Sci. Lett., 307(1–2), 156160 (doi: 10.1016/j.epsl.2011.04.026)
Hallet, B (1996) Glacial quarrying: a simple theoretical model. Ann. Glaciol., 22, 18
Hallikainen, MT, Ulaby, FT and Abdelrazik, M (1986) Dielectric properties of snow in the 3 to 37 GHz range. IEEE Trans. Antennas Propag., 34(11),13291340 (doi: 10.1109/TAP.1986.1143757)
Hanssen, RF (2001) Radar interferometry: data interpretation and error analysis. Kluwer Academic, Dordrecht
Hensley, S, Zebker, H, Jones, C, Michel, T, Muellerschoen, R and Chapman, B (2009a) First deformation results using the NASA/JPL UAVSAR instrument. In Proceedings of 2nd Asian–Pacific Conference on Synthetic Aperture Radar (APSAR), 26–30 October 2009, Xian, Shanxi, China. Institute of Electrical and Electronics Engineers, Piscataway, NJ
Hensley, S and 7 others (2009b) Residual motion estimation for UAVSAR: implications of an electronically scanned array. In Proceedings of 2009 IEEE Radar Conference, 4–8 May 2009, Pasadena, CA, USA. Institute of Electrical and Electronics Engineers, Piscataway, NJ, 15
Hetland, EA, Musé, P, Simons, M, Lin, YN, Agram, PS and DiCaprio, CJ (2012) Multiscale InSAR Time Series (MInTS) analysis of surface deformation. J. Geophys. Res., 117(B2), B02404 (doi: 10.1029/2011J B008731)
Hewitt, IJ (2013) Seasonal changes in ice sheet motion due to melt water lubrication. Earth Planet. Sci. Lett., 371–372, 1625 (doi: 10.1016/j.epsl.2013.04.022)
Howat, IM, Tulaczyk, S, Waddington, E and Björnsson, H (2008) Dynamic controls on glacier basal motion inferred from surface ice motion. J. Geophys. Res., 113(F3), F03015 (doi: 10.1029/2007JF000925)
Iken, A and Bindschadler, RA (1986) Combined measurements of subglacial water pressure and surface velocity of Findelengletscher, Switzerland: conclusions about drainage system and sliding mechanism. J. Glaciol., 32(110), 101119
Ishimaru, A (1978) Wave propagation and scattering in random media. Academic Press, New York
Iverson, NR (2012) A theory of glacial quarrying for landscape evolution models. Geology, 40(8), 679682 (doi: 10.1130/G33079.1)
Jóhannesson, H and Sæmundsson, K. (1998) Geological map of Iceland, 1 : 500 000. Icelandic Museum of Natural History and Icelandic Geodetic Survey, Reykjavík
Jóhannesson, T and 7 others (2013) Ice-volume changes, bias-estimation of mass-balance measurements and changes in subglacial lakes derived by lidar-mapping of the surface of Icelandic glaciers. Ann. Glaciol., 54(63 Pt 1), 6374 (doi: 10.3189/2013AoG63A422)
Joughin, I, Fahnestock, M, MacAyeal, D, Bamber, JL and Gogineni, P (2001) Observation and analysis of ice flow in the largest Greenland ice stream. J. Geophys. Res., 106(D24), 34 02134 034 (doi: 10.1029/2001JD900087)
Joughin, I and 6 others (2012) Seasonal to decadal scale variations in the surface velocity of Jakobshavn Isbræ, Greenland: observation and model-based analysis. J. Geophys. Res., 117(F2), F02030 (doi: 10.1029/2011JF002110)
Kamb, B (1987) Glacier surge mechanism based on linked cavity configuration of the basal water conduit system. J. Geophys. Res., 92(B9), 90839100 (doi: 10.1029/JB092iB09p09083)
Kamb, B (2001) Basal zone of the West Antarctic ice streams and its role in lubrication of their rapid motion. In Alley, RB and Bindschadler, RA eds. The West Antarctic ice sheet: behavior and environment. American Geophysical Union, Washington, DC, 157199
Khankhoje, UK, Van Zyl, JJ and Cwik, TA (2012) Computation of radar scattering from heterogeneous rough soil using the finite-element method. IEEE Trans. Geosci. Remote Sens., 51(6), 34613469 (doi: 10.1109/TGRS.2012.2225431)
Lohman, RB and Simons, M (2005) Some thoughts on the use of InSAR data to constrain models of surface deformation: noise structure and data downsampling. Geochem. Geophys. Geosyst., 6(Q1), Q01007 (doi: 10.1029/2004GC000841)
MacAyeal, DR (1989) Large-scale ice flow over a viscous basal sediment: theory and application to Ice Stream B, Antarctica. J. Geophys. Res., 94(B4), 40714087 (doi: 10.1029/JB094iB04p04071)
Magnússon, E, Rott, H, Björnsson, H and Pálsson, F (2007) The impact of jökulhlaups on basal sliding observed by SAR interferometry on Vatnajökull, Iceland. J. Glaciol., 53(181), 232240 (doi: 10.3189/172756507782202810)
Magnússon, E, Björnsson, H, Rott, H and Pálsson, F (2010) Reduced glacier sliding caused by persistent drainage from a subglacial lake. Cryosphere, 4(1), 1320
Magnússon, E and 8 others (2011) Localized uplift of Vatnajökull, Iceland: subglacial water accumulation deduced from InSAR and GPS observations. J. Glaciol., 57(203), 475484 (doi: 10.3189/002214311796905703)
Mätzler, C (1998) Improved Born approximation for scattering of radiation in a granular medium. J. Appl. Phys., 83(11), 61116117 (doi: 10.1063/1.367496)
Misra, P and Enge, P (2006) Global positioning system: signals, measurements, and performance, 2nd edn. Ganga-Jamuna Press, Lincoln, MA
Nolan, M and Fatland, DR (2003) Penetration depth as a DInSAR observable and proxy for soil moisture. IEEE Trans. Geosci. Remote Sens., 41(3), 532537 (doi: 10.1109/TGRS.2003. 809931)
Nolan, M, Fatland, DR and Hinzman, L (2003) DInSAR measurement of soil moisture. IEEE Trans. Geosci. Remote Sens., 41(12), 28022813 (doi: 10.1109/TGRS.2003.817211)
Nye, JF (1957) The distribution of stress and velocity in glaciers and ice-sheets. Proc. R. Soc. London, Ser. A, 239(1216), 113133 (doi: 10.1098/rspa.1957.0026)
Ortega Culaciati, FH (2013) Aseismic deformation in subduction megathrusts: central Andes and north-east Japan. (PhD thesis, California Institute of Technology)
Oveisgharan, S and Zebker, HA (2007) Estimating snow accumulation from InSAR correlation observations. IEEE Trans. Geosci. Remote Sens., 45(1), 1020 (doi: 10.1109/TGRS.2006.886196)
Palmer, S, Shepherd, A, Björnsson, H and Pálsson, F (2009) Ice velocity measurements of Langjökull, Iceland, from interferometric synthetic aperture radar (InSAR). J. Glaciol., 55(193), 834838 (doi: 10.3189/002214309790152573)
Riel, B, Simons, M, Agram, P and Zhan, Z (2014) Detecting transient signals in geodetic time series using sparse estimation techniques. J. Geophys. Res., 119(6), 51405160 (doi: 10.1002/2014JB011077)
Rignot, E and Kanagaratnam, P (2006) Changes in the velocity structure of the Greenland Ice Sheet. Science, 311(5673), 986990 (doi: 10.1126/science.1121381)
Rignot, E, Mouginot, J and Scheuchl, B (2011) Ice flow of the Antarctic Ice Sheet. Science, 333(6048), 14271430 (doi: 10.1126/science.1208336)
Rodriguez, E and Martin, JM (1992) Theory and design of interferometric synthetic aperture radars. IEE Proc. F, 139(2), 147159
Rosen, PA and 6 others (2000) Synthetic aperture radar interferometry. IEEE Proc., 88(3), 333385 (doi: 10.1109/5.838084)
Schoof, C (2010) Ice-sheet acceleration driven by melt supply variability. Nature, 468(7325), 803806 (doi: 10.1038/nature09618)
Shepherd, A, Hubbard, A, Nienow, P, McMillan, M and Joughin, I (2009) Greenland ice sheet motion coupled with daily melting in late summer. Geophys. Res. Lett., 36(1), L01501 (doi: 10.1029/2008GL035758)
Stuart, AM (2010) Inverse problems: a Bayesian perspective. Acta Num., 19, 451559 (doi: 10.1017/S0962492910000061)
Tarantola, A (2005) Inverse problem theory and methods for model parameter estimation. Society for Industrial and Applied Mathematics, Philadelphia, PA
Tulaczyk, SM, Kamb, B and Engelhardt, HF (2000) Basal mechanics of Ice Stream B, West Antarctica. II. Undrained-plastic-bed model. J. Geophys. Res., 105(B1), 483494 (doi: 10.1029/1999JB900328)
Ulaby, FT, Moore, RK and Fung, AK (1986) Microwave remote sensing, active and passive. Vol. 3. From theory to applications. Addison-Wesley, Reading, MA
Werder, MA, Hewitt, IJ, Schoof, CG and Flowers, GE (2013) Modeling channelized and distributed subglacial drainage in two dimensions. J. Geophys. Res., 118(4), 21402158 (doi: 10.1002/jgrf. 20146)
Zebker, HA and Villasenor, J (1992) Decorrelation in interferometric radar echoes. IEEE Trans. Geosci. Remote Sens., 30(5), 950959 (doi: 10.1109/36.175330)
Zebker, HA, Rosen, PA and Hensley, S (1997) Atmospheric effects in interferometric synthetic aperture radar surface deformation and topographic maps. J. Geophys. Res., 102(B4), 75477563 (doi: 10.1029/96JB03804)
Zumberge, JF, Heflin, MB, Jefferson, DC, Watkins, MM and Webb, FH (1997) Precise point positioning for the efficient and robust analysis of GPS data from large networks. J. Geophys. Res., 102(B3), 50055017 (doi: 10.1029/96JB03860)
Zwally, HJ, Abdalati, W, Herring, T, Larson, K, Saba, J and Steffen, K (2002) Surface melt-induced acceleration of Greenland ice-sheet flow. Science, 297(5579), 218222 (doi: 10.1126/science.1072708)
Recommend this journal

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

Journal of Glaciology
  • ISSN: 0022-1430
  • EISSN: 1727-5652
  • URL: /core/journals/journal-of-glaciology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



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