Remote Sensing Analysis of Changes in Chorabari Glacier, Central Himalaya, India

Abstract

In this study, mass balance for Chorabari glacier of the Central Himalaya, India has been estimated. This glacier has been considered for the case study as it feeds the Mandakini River and was one of the reasons for flash floods in Rudraprayag district, Uttarakhand in 2013. The observations are based on glacier area/length change and rate of melting in the multidecade (1976-2016) using Landsat data. The study estimates an overall decrease in area at 0.8% per year. Elevation change has been studied using geodetic method utilizing shuttle radar topography mission and TanDEM-X datasets, which have shown a decrease in elevation in 16 years (2000-16). From these remotely observed parameters, a negative mass balance for the decade 2000-11 indicates glacier retreat. This study highlights the applicability of optical and radar remote sensing for the Himalayan glaciers, for better disaster management and understanding glacier dynamics in response to climate change.

Spatial distribution of decadal ice-thickness change and glacier stored water loss in the Upper Ganga basin, India during 2000–2014

“…a −1 for the period 2000–2014. Further, in our previous study 18 , a specific mass balance of −0.66 ± 0.13 m. w. eq. a −1 for the decade 2000–2016 was reported for Chorabari glacier, whereas here we estimate for 2000–2014 the specific mass balance as −0.63 ± 0.04 m. w. eq.…”

“…With a debris cover of >1 m, this glacier in fact shows no terminus retreat during the study period 2003–2010 27 . However, over multi-decade (1976–2016) the glacier has shown significant retreat rate 18 . Hence, the debris cover thickness can either reduce or enhance the glacier ice melt.…”

“…Geodetic method helps in estimation of elevation changes using DEMs, which can be directly utilized for mass change predictions as well. Previous geodetic studies in the Indian Himalaya have been accomplished using various remote sensing satellites like ICESat laser altimetry 1,7 , SRTM 7–9 , ASTER 10,11 , Cartosat stereo pairs 9,12 , SPOT data 7,8,13–15 and recently (since 2010) TanDEM-X/TerraSAR-X DEMs 16–18 . The major advantage of the TanDEM-X/TerraSAR-X pair is that the dataset provides the first space-borne interferometric SAR pair with a continuous single-baseline InSAR data which can be harnessed to generate accurate DEMs.…”

GLACIER ICE MASS CHANGES IN CENTRAL HIMALAYAS DURING 2000-2014 USING TanDEM- X DATA

“…The thin layer of debris cover and steep slope could be the reason for the rather high glacier ice/snow/firn melt in the accumulation zone. Our specific mass balance observations compare with the estimates in Bandyopadhyay et al, 2018, however comparative analysis with mass balance records using glaciological measurements differ. The reason could be the sparse point observations which have been averaged over the entire glacier as well the difference in the time period.…”

Glacier elevation and mass changes in Himalayas during 2000–2014

“…Previous studies in Himalayas have been carried out using either laser altimetry (Kääb et al, 2012) or digital elevation models (DEMs) generated from optical stereo-pairs and Synthetic Aperture Radar (SAR) using interferometry (Agarwal et al, 2017;Berthier et al, 2007;Bolch et al, 2017;Gardelle et al, 2012Gardelle et al, , 2013. With the recent release of TanDEM-X/TerraSAR-X (since 2010), the geodetic method has been implemented in selective regions 10 of Karakoram-Himalayas using solely SAR images (SRTM and TanDEM-X dataset) (Bandyopadhyay et al, 2018;Braun, 2016, 2018). The major advantage of these dataset is the weather independent coverage, as in tropical regions, cloud cover limits visibility to optical images especially in the end of ablation season (September end).…”