Glacier retreat, dynamics and bed overdeepenings of Parkachik Glacier, Ladakh Himalaya, India

• Published in: Annals of glaciology pp. 1 - 14
• Main Authors: Rana, Ajay Singh, Kunmar, Pankaj, Mehta, Manish, Kumar, Vinit
• Format: Journal Article
• Language: English
• Published: Cambridge University Press 18-07-2023
• Subjects: Glacier changes; ice thickness; Ladakh Himalaya; surface ice velocity; Suru River valley
• ISSN: 0260-3055; 1727-5644
• DOI: 10.1017/aog.2023.50

Abstract
This study describes the morphological and dynamic changes of Parkachik Glacier, Suru River valley, Ladakh Himalaya, India. We used medium-resolution satellite images; CORONA KH-4, Landsat and Sentinel-2A from 1971–2021, and field surveys between 2015 and 2021. In addition, we used the laminar flow-based Himalayan Glacier Thickness Mapper and provide results for recent margin fluctuations, surface ice velocity, ice thickness, and identified glacier-bed overdeepenings. The results revealed that overall the glacier retreated by −210.5 ± 80 m with an average rate of 4 ± 1 m a
−1
between 1971 and 2021. Whereas a field study suggested that the glacier retreat increased to −123 ± 72 m at an average rate of −20 ± 12 m a
−1
between 2015 and 2021. Surface ice velocity was estimated using COSI-Corr on the Landsat data. Surface ice velocity in the lower ablation zone was 45 ± 2 m a
−1
in 1999–2000 and 32 ± 1 m a
−1
in 2020–2021, thus reduced by 28%. Further, the maximum thickness of the glacier is estimated to be ~441 m in the accumulation zone, while for glacier tongue it is ~44 m. The simulation results suggest that if the glacier continues to retreat at a similar rate, three lakes of different dimensions may form in subglacial overdeepenings.