Estimating Spatial and Temporal Variability in Surface Kinematics of the Inylchek Glacier, Central Asia, using TerraSAR–X Data

Abstract

We use 124 scenes of TerraSAR-X data that were acquired in 2009 and 2010 to analyse the spatial and temporal variability in surface kinematics of the debris-covered Inylchek Glacier, located in the Tien Shan mountain range in Central Asia. By applying the feature tracking method to the intensity information of the radar data and combining the results from the ascending and descending orbits, we derive the surface velocity field of the glaciated area. Analysing the seasonal variations over the upper part of the Southern Inylchek branch, we find a temperature-related increase in velocity from 25 cm/d up to 50 cm/d between spring and summer, with the peak occurring in June. Another prominent velocity peak is observable one month later in the lower part of the Southern Inylchek branch. This area shows generally little motion, with values of approximately 5-10 cm/d over the year, but yields surface kinematics of up to 25 cm/d during the peak period. Comparisons of the dates of annual glacial lake outburst floods (GLOFs) of the proglacial Lake Merzbacher suggest that this lower part is directly influenced by the drainage, leading to the observed mini-surge, which has over twice the normal displacement rate. With regard to the GLOF and the related response of Inylchek Glacier, we conclude that X-band radar systems such as TerraSAR-X have a high potential for detecting and characterising small-scale glacial surface kinematic variations and should be considered for future inter-annual glacial monitoring tasks.Remote Sens. 2014, 6 9240

Ten Years of Experience with Scientific TerraSAR-X Data Utilization

“…The influence of climate and the climate variability on ice-and snow-covered areas of the Earth (see Figure 6) is investigated by 17 percent of the proposals. Almost 50 percent concentrate on the observation of ice caps and glaciers including monitoring of glacier outlines [82] and their spatiotemporal variability [83,84] and, changing of calving rates at the shore line [85]. The major application field, however, is the determination of the glacier flow velocity [86,87], an essential factor for the assessment and understanding of mountain [88][89][90], rock [91] and polar glacier dynamics.…”

Three-Dimensional Displacement Fields from InSAR through Tikhonov Regularization and Least-Squares Variance Component Estimation

“…Moreover, the near-polar orbiting of SAR missions leads to low sensitivity of the north component with respect to two other components (Rocca 2003;Wright et al 2004). For large displacement fields, range and azimuth measurements can be combined to retrieve the 3D deformation (Neelmeijer et al 2014). In the absence of azimuth measurement, however, it is possible to stabilize the inversion process by imposing additional constraints, a process that is generally referred to as regularization.…”

Geodetic Monitoring Networks: GNSS-Derived Glacier Surface Velocities at the Global Change Observatory Inylchek (Kyrgyzstan)

“…The latter surface velocities were calculated over 8 images taken between July 24th and August 26th 2010 by applying the Amplitude Tracking Method. Details for the TerraSAR-X processing and accuracy assessments are given in Neelmeijer et al (2014). The resolution of the strip map data of 25 m allows the extraction of only one collocated motion value of 0.34 m/day (average of four TerraSAR-X data pairs).…”