Estimation of Ice Thickness of the Satopanth Glacier, Central Himalaya Using Ground Penetrating Radar

Abstract

Total volume of stored ice in the Himalayan glaciers is an important quantity for water resource management of the Himalayan catchments. However, direct measurement of glacier-ice thickness is rare in the Indian Himalaya. We have estimated the ice thickness of the debris-covered Satopanth Glacier (SPG) using a ground penetrating radar (GPR). Multiple bistatic, unshielded antennae with frequencies of 16, 20, 40 and 80 MHz were used for this purpose. We have done GPR surveys at various locations over the ablation zone of SPG. However, satisfactory results were obtained only on two transects. Near the glacier snout, a transverse GPR profile shows an ice thickness of 38  3.5-50  3.5 m. We have obtained 98  7-112  7 m ice thickness at a longitudinal transect in the upper ablation zone. To measure the speed of the radar waves in ice, a common midpoint survey was carried out. Our results for the speed of the electromagnetic waves are slightly lower than the standard values of such waves through pure ice.

Challenges in Understanding the Variability of the Cryosphere in the Himalaya and Its Impact on Regional Water Resources

“…Studies related to ice thickness date to the 1960s (Raina, 2009), and field investigations are still ongoing in sporadic nature at accessible glaciers in the Himalaya. However, only a few glaciers are being surveyed using GPR (e.g., Azam et al, 2012;Vincent et al, 2016;Mishra et al, 2018;Pritchard et al, 2020). GPR survey-based ice thickness measurements are available for only around 21 glaciers and that too at different time intervals (Kulkarni et al, 2021).…”

Glacier-Surface Velocity Derived Ice Volume and Retreat Assessment in the Dhauliganga Basin, Central Himalaya – A Remote Sensing and Modeling Based Approach

“…Ground penetrating radar (GPR) measurements along five transects with a positional accuracy of ±0.1 m and overall uncertainty of ±15 m in ice thickness were used for Chotta Shigri glacier system to calibrate the model inputs (Azam et al, 2012). Similarly, GPR measurements of ice thickness along two transects with a positional accuracy of 1 cm and 7% uncertainty in ice thickness have been used to validate the model for Satopanth glacier system (Mishra et al, 2018). In addition to this, spatially distributed ice thickness of the HF-model by Huss and Farinotti (2012) were employed to compare modeled ice thickness of the calibration and validation glaciers and one glacier in the Dhauliganga basin.…”

“…The glacier-ice thickness distribution is calculated using the same set of model inputs as that in the calibration setup. Since f was calibrated on the Chotta Shigri glacier to a value of 0.8, we validate the model by directly comparing the modeled ice thickness (f = 0.8) of Satopanth glacier to the GPR measurements available along two transects, one near the terminus and the other at 10 km upstream of the snout (Mishra et al, 2018). Figure 5 shows the glacier-surface velocity field, modeled ice thickness distribution and the modeled glacier-bed profiles (f = 0.6 and f = 0.8).…”

“…(B) Distributed ice thickness of the Satopanth glacier. (C,D) Comparison of the model-derived glacier bed profiles (f = 0.6 and f = 0.8) with the GPR measurements byHuss and Farinotti (2012) andMishra et al (2018).…”

Efficiency of artificial neural networks for glacier ice-thickness estimation: a case study in western Himalaya, India

“…Field-based ground penetrating radar (GPR) surveys (Hubbard and Glasser, 2005), one of the best available methods to estimate the ice thickness, have been used on glaciers worldwide (Pettersson and others, 2003; Pattyn and others, 2009; Wagnon and others, 2013). Due to rough terrain, harsh climatic conditions and high expedition costs in the Himalaya, GPR surveys have been conducted for ice-thickness estimates only for a few selected glaciers: Khumbu (Iwata and others, 1980), Dokriani (Gergan and others, 1999), Chhota Shigri (Azam and others, 2012; Singh and others, 2012), Mera (Wagnon and others, 2013), Changri Nup (Vincent and others, 2016), Lirung (McCarthy and others, 2017) and Satopanth (Mishra and others, 2018) Glaciers.…”