Glacier dynamics in the Canadian High Arctic from RADARSAT-1 speckle tracking

The surface velocities of 11 glaciers from Axel Heiberg and Ellesmere islands in the Canadian High Arctic were monitored between 2000 and 2004 using RADARSAT-1 data and the speckle tracking technique. The results show that the flow of large Arctic outlet glaciers is fast and variable, with speeds of several hundreds of metres a year being common and ~1 km·a–1 attainable under surge conditions. At any one time several glaciers appeared to be actively surging, and active phases of a minimum of 5 years have been observed. Other glaciers demonstrated significant interannual variations in flow rates, even though not considered to be surge type. These observations of short- to medium-term flow instability have implications for the interpretation of ice thickness and ice surface height measurements. Ice thickness changes resulting from short-term, local redistribution of glacier mass will need to be differentiated from mass-balance trends due to climate forcing. Where ice thickness measurements are available, they are combined with the velocity results to estimate calving rates. In a few cases they are also used to derive theoretical balance velocities to compare with the velocity measurements.

[1]  Mattar,et al.  Tributaries of West Antarctic Ice Streams Revealed by RADARSAT Interferometry. , 1999, Science.

[2]  Tazio Strozzi,et al.  Is there a single surge mechanism? Contrasts in dynamics between glacier surges in Svalbard and other regions , 2003 .

[3]  Ian Joughin,et al.  Ice-sheet velocity mapping: a combined interferometric and speckle-tracking approach , 2002, Annals of Glaciology.

[4]  R. Armstrong,et al.  The Physics of Glaciers , 1981 .

[5]  Ian Joughin,et al.  Observations of ice‐sheet motion in Greenland using satellite radar interferometry , 1995 .

[6]  C. Ommanney.  A study in glacier inventory : the ice masses of Axel Heiberg Island, Canadian Arctic archipelago , 1969 .

[7]  N H Short,et al.  Potential for RADARSAT-2 interferometry: glacier monitoring using speckle tracking , 2004 .

[8]  R. Bindschadler,et al.  Application of image cross-correlation to the measurement of glacier velocity using satellite image data , 1992 .

[9]  J. Hagen,et al.  The duration of the active phase on surge-type glaciers: contrasts between Svalbard and other regions , 1991, Journal of Glaciology.

[10]  Søren Nørvang Madsen,et al.  Three-dimensional surface velocities of Storstrømmen glacier, Greenland, derived from radar interferometry and ice-sounding radar measurements , 2003 .

[11]  Ron Kwok,et al.  Estimation of ice-sheet motion using satellite radar interferometry: method and error analysis with application to Humboldt Glacier, Greenland , 1996, Journal of Glaciology.

[12]  R. Koerner.  Glaciers of the arctic Islands glaciers of the High Arctic Islands , 2002 .

[13]  Luke Copland,et al.  Links between short-term velocity variations and the subglacial hydrology of a predominantly cold polythermal glacier , 2003, Journal of Glaciology.

[14]  R. Goldstein,et al.  Satellite Radar Interferometry for Monitoring Ice Sheet Motion: Application to an Antarctic Ice Stream , 1993, Science.

[15]  Julian A. Dowdeswell,et al.  Form and flow of the Devon Island Ice Cap, Canadian Arctic , 2004 .

[16]  Urs Wegmüller,et al.  Glacier motion estimation using SAR offset-tracking procedures , 2002, IEEE Trans. Geosci. Remote. Sens..

[17]  Luke Copland,et al.  The distribution and flow characteristics of surge-type glaciers in the Canadian High Arctic , 2003, Annals of Glaciology.

[18]  Charles F. Raymond,et al.  How do glaciers surge? A review , 1987 .

[19]  G. Hattersley-Smith.  Recent observations on the surging Otto Glacier, Ellesmere Island , 1969 .

[20]  R. Bamler,et al.  Interferometric stereo radargrammetry: absolute height determination from ERS-ENVISAT interferograms , 2000, IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing the Environment. Proceedings (Cat. No.00CH37120).

[21]  Eric Rignot,et al.  Ice flow dynamics of the Greenland Ice Sheet from SAR interferometry , 1995, Geophysical Research Letters.

[22]  K. Jezek,et al.  Velocities and Flux of the Filchner Ice Shelf and its Tributaries Determined from Speckle Tracking Interferometry , 2001 .

[23]  Tazio Strozzi,et al.  The initiation of glacier surging at Fridtjovbreen, Svalbard , 2003, Annals of Glaciology.

[24]  Helgi Björnsson,et al.  Surges of glaciers in Iceland , 2003, Annals of Glaciology.

[25]  Ian R. Joughin,et al.  Interferometric estimation of three-dimensional ice-flow using ascending and descending passes , 1998, IEEE Trans. Geosci. Remote. Sens..

[26]  M. Noguer,et al.  Climate change 2001: The scientific basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change , 2002 .

[27]  P. Vachon,et al.  InSAR results from the RADARSAT Antarctic Mapping Mission data: estimation of glacier motion using a simple registration procedure , 1998, IGARSS '98. Sensing and Managing the Environment. 1998 IEEE International Geoscience and Remote Sensing. Symposium Proceedings. (Cat. No.98CH36174).

[28]  The Initiation , 2007, Witchfinders.

[29]  T. Murray,et al.  Geometric evolution and ice dynamics during a surge of Bakaninbreen, Svalbard , 1998 .

[30]  Tazio Strozzi,et al.  Ice dynamics during a surge of Sortebræ, East Greenland , 2002, Annals of Glaciology.

[31]  Yi-Hsing Tseng,et al.  Automatic tracking of crevasses on satellite images , 1995 .

[32]  Karim E. Mattar,et al.  Influence of ionospheric electron density fluctuations on satellite radar interferometry , 2000 .

[33]  Tazio Strozzi,et al.  ERS SAR feature-tracking measurement of outlet glacier velocities on a regional scale in East Greenland , 2003, Annals of Glaciology.

[34]  A. Luscombe,et al.  The RADARSAT Synthetic Aperture Radar Development , 1993 .

[35]  Søren Nørvang Madsen,et al.  Combining SAR interferometry and the equation of continuity to estimate the three-dimensional glacier surface-velocity vector , 1999 .