Water level changes at an ice‐dammed lake in west Greenland inferred from InSAR data

[1] We detect ground displacements around an ice-dammed lake (Lake Tiningnilik) in west Greenland, using ERS1/2 and Envisat radar interferograms. We associate those displacements with draining episodes (jokulhlaups in Icelandic) that occurred in 1993 and 2003. We confirm those episodes in backscatter intensity images. By assuming a 7.5 meter/year increase in water level and using an elastic loading model, we predict a rate and spatial pattern for the deformation that are in good agreement with the observations. By generating digital elevation models from radar interferograms for both the drained and undrained stages, we validate the inferred lake level changes.

[1]  Laurence C. Smith,et al.  Estimation of erosion, deposition, and net volumetric change caused by the 1996 Skeiðarársandur jökulhlaup, Iceland, from Synthetic Aperture Radar Interferometry , 2000 .

[2]  Søren Nørvang Madsen,et al.  Synthetic aperture radar interferometry-Invited paper , 2000 .

[3]  John C. Curlander,et al.  Synthetic Aperture Radar: Systems and Signal Processing , 1991 .

[4]  Charles Werner,et al.  Accuracy of topographic maps derived from ERS-1 interferometric radar , 1994, IEEE Trans. Geosci. Remote. Sens..

[5]  R. Hanssen.  Radar Interferometry: Data Interpretation and Error Analysis , 2001 .

[6]  W. Farrell.  Deformation of the Earth by surface loads , 1972 .

[7]  P. Rosen,et al.  SYNTHETIC APERTURE RADAR INTERFEROMETRY TO MEASURE EARTH'S SURFACE TOPOGRAPHY AND ITS DEFORMATION , 2000 .

[8]  Ian G. Cumming,et al.  Digital Processing of Synthetic Aperture Radar Data: Algorithms and Implementation , 2005 .

[9]  Fuk K. Li,et al.  Synthetic aperture radar interferometry , 2000, Proceedings of the IEEE.

[10]  S. Ekholm,et al.  A full coverage, high-resolution, topographic model of Greenland computed from a variety of digital elevation data , 1996 .

[11]  Urs Wegmüller,et al.  Gamma SAR processor and interferometry software , 1997 .

[12]  S. P. Anderson,et al.  Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska , 2003 .

[13]  Timothy H. Dixon,et al.  Space‐based measurements of sheet‐flow characteristics in the Everglades wetland, Florida , 2004 .

[14]  Helgi Björnsson,et al.  Hydrological characteristics of the drainage system beneath a surging glacier , 1998, Nature.

[15]  D. Alsdorf,et al.  Interferometric radar measurements of water level changes on the Amazon flood plain , 2000, Nature.

[16]  K. Feigl,et al.  Radar interferometry and its application to changes in the Earth's surface , 1998 .

[17]  John M. Melack,et al.  Water level changes in a large Amazon lake measured with spaceborne radar interferometry and altimetry , 2001 .

[18]  Laurence C. Smith,et al.  Emerging Applications of Interferometric Synthetic Aperture Radar (InSAR) in Geomorphology and Hydrology , 2002 .

[19]  M. Ritzwoller,et al.  Monte-Carlo inversion for a global shear-velocity model of the crust and upper mantle , 2002 .

[20]  M. Roberts.  JÖkulhlaups: A reassessment of floodwater flow through glaciers , 2005 .

[21]  P. Visser,et al.  Precise orbit determination and gravity field improvement for the ERS satellites , 1998 .