Topography and accumulation rate as controls of asynchronous surging behaviour in the eastern and western branches of the Western Kunlun Glacier, Northwestern Tibetan Plateau

ABSTRACT

The western Kunlun main peak region is among the areas in High Mountain Asia where surge-type glaciers are highly concentrated. Here, we analyse the surging characteristics of the eastern and western branches of the Western Kunlun Glacier and the factors controlling the asynchronous behaviour of their surges. The eastern branch entered an unstable state in 1999 and remained so until the culmination of its surge in the summer of 2019, spanning 21 years. Conversely, the surge of the western branch commenced in the summer of 2020. The surge duration for this glacier was four years, characterized by a rapid acceleration and deceleration process. Based on the glacier surge characteristics, we posit that western branch of Western Kunlun Glacier was influenced by hydrological mechanisms, while eastern branch was affected by subglacial thermal processes. These process intensifies crevasse formation on the glacial surface, providing conduits for surface meltwater to reach the glacier bed, thus elevating subglacial water pressure. The difference of subglacial hydrology and thermal processes caused by different subglacial topography and mass accumulation rates was the main factor of the asynchronous behaviour of the west and east branches of the West Kunlun glacier.

KEYWORDS:

• Mechanism of glacier surge
• glacier surface elevation
• glacier velocity
• Western Kunlun
• remote sensing

Acknowledgements

We thank the United States Geological Survey (USGS) for the Landsat data (https://www.usgs.gov/), the National Aeronautics and Space Administration (NASA) for the NASADEM, ITS_LIVE, MCD43A3 and ASTER-L1A (https://cmr.earthdata.nasa.gov/), Japan Aerospace Exploration Agency (JAXA) for the AW3D30 DEM (https://www.eorc.jaxa.jp/), the European Space Agency (ESA) for the COP30 DEM (https://spacedata.copernicus.eu/), and University of California, Santa Barbara for the CHIRPS (https://chc.ucsb.edu/data/chirps).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study can be obtained from the corresponding author upon reasonable request.

Additional information

Funding

This study was supported by the Top-notch Talent of the Qinghai Province ‘Kunlun Talent. High-end Innovation and Entrepreneurship Talent’ program [grant no 2023-QLGKLYCZX-001], the Postdoctoral research project, Faculty of Geography, Yunnan Normal University [grant number 01300205020516079], the Project Supported by Key Laboratory of Resource Environment and Sustainable Development of Oasis, Gansu Province [grant no GORS202302], the Enhancement Program for Research Capabilities in the Faculty of Geography [grant no 01300205020516083/002], the Postdoctoral research start-up project of Yunnan Normal University [grant number 01300205020503329], and the Researcher Development program of Qinghai University of Science and Technology [grant number 2023011wys007].