Mass-balance observation, reconstruction and sensitivity of Stok glacier, Ladakh region, India, between 1978 and 2019

• Published in: Journal of Glaciology
• Main Authors: Soheb, Mohd, Ramanathan, Alagappan, Angchuk, Thupstan, Mandal, Arindan, Kumar, Naveen, Lotus, Sonam
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2020
• Subjects: Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/jog.2020.34; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020000349

Abstract We present the first-ever mass-balance (MB) observation (2014–19), reconstruction (between 1978 and 2019) and sensitivity of debris-free Stok glacier (33.98°N, 77.45°E), Ladakh Region, India. In-situ MB was negative throughout the study period except in 2018/19 when the glacier witnessed a balanced condition. For MB modelling, three periods were considered based on the available data. Period I (1978–87, 1988/89) witnessed a near balance condition (−0.03 ± 0.35 m w.e. a −1 ) with five positive MB years. Whereas Period II (1998–2002, 2003–09) and III (2011–19) experienced high (−0.9 ± 0.35 m w.e. a −1 ) and moderate (−0.46 ± 0.35 m w.e. a −1 ) negative MBs, respectively. Glacier area for these periods was derived from the Corona, Landsat and PlanetScope imageries using a semi-automatic approach. The in-situ and modelled MBs were in good agreement with RMSE of 0.23 m w.e. a −1 , R 2 = 0.92, P < 0.05. The average mass loss was moderate (−0.47 ± 0.35 m w.e. a −1 ) over 28 hydrological years between 1978 and 2019. Sensitivity analysis showed that the glacier was more sensitive to summer temperature (−0.32 m w.e. a −1 °C −1 ) and winter precipitation (0.12 m w.e. a −1 for ± 10%). It was estimated that ~27% increase in precipitation is required on Stok glacier to compensate for the mass loss due to 1°C rise in temperature.