Abstract

Himalayan glaciers are distinct by their surface characteristics, such as debris-cover, supra/proglacial lakes, ice-cliff, and tributaries' contributions, thus complicating their surface velocity pattern and their response towards climate warming. While remote sensing and modelled surface velocity estimation are valuable on a larger scale, in situ high-resolution data is crucial to validate them. In this study, four glaciers (Batal, Sutri Dhaka, Samudra Tapu, and Gepang Gath) from Chandra Basin were monitored to measure point-wise surface displacement using a static GNSS system during 2017–2018. Among them, the highest surface velocity was observed over Samudra Tapu (∼64.3 ma⁻¹), a large and clean-type glacier, while the lowest was for Batal (∼6.2 ma⁻¹), a small and debris-covered glacier. Our study highlighted the contrasting behaviour of lake-terminating and debris-covered glaciers for the surface velocity and also emphasize the additional control of the slope, supraglacial lake, debris thickness and convergence of glacier channels on the glacier surface velocity.

摘要

喜马拉雅冰川因其表面特征而不同，例如碎片覆盖、上冰湖、冰崖和支流的贡献，从而使它们的表面速度模式及其对气候变暖的反应复杂化。虽然遥感和模拟地表速度估计在更大范围内很有价值，但原位高分辨率数据对于验证它们至关重要。在这项研究中，在 2017-2018 年期间，使用静态 GNSS 系统监测了来自钱德拉盆地的四个冰川（Batal、Sutri Dhaka、Samudra Tapu 和 Gepang Gath）以测量逐点表面位移。其中，最高的表面速度在萨穆德拉塔普（~64.3 ma ^-1），一个大型清洁型冰川，而最低的是巴塔尔（~6.2 ma ^-1)，一个被碎片覆盖的小冰川。我们的研究强调了湖泊终止和碎片覆盖的冰川对表面速度的对比行为，并强调了斜坡、冰上湖泊、碎片厚度和冰川通道收敛对冰川表面速度的额外控制。