The Kangri Karpo Mountain Range on the Qinghai-Tibet Plateau frequently experiences glacial lake outburst floods (GLOFs). This study assessed the risk of outburst floods for Guangxieco Proglacial Lake (GPL) in this Mountain Range as a typical case to reveal the effects of rapid glacial change. The area of Gongzo Glacier behind GPL decreased by 7.39 +/- 0.10% from 1987 to 2019, while this glacier advanced by 32.45 m from 5 June to 27 October in 1988. Guangxieco Proglacial Lake decreased from 0.42 +/- 0.03 km(2) in 1987 to 0.19 +/- 0.03 km(2) in 1988 and then continuously expanded to 0.43 +/- 0.04 km(2) in 2019. Heavy precipitation occurred before 15 July 1988, when no supraglacial lake existed. Meanwhile, sustained abnormally high air temperature caused accelerated glacier and snow melting. Since 1988, a larger volume of rainfall and meltwater impounded by the ice wall caused an increase in the basal water pressure in the glacier. A significant increase in winter mass balance has caused a further increase in the downward gravity component of glacier sliding. As a result, the glacier advanced rapidly while reopening previously blocked subglacial drainage systems. The accumulating subglacial water rapidly drained into the Proglacial Lake causing an elevated lake level and a GLOF event. However, the current area of the glacial lake has recovered to the scale present before the outburst in 1988. Therefore, local government agencies and the local community should improve early warning systems and take measures designed to prevent a new GLOF and to minimize the risk of a recurrence of a GPL outburst.

Study region: The northern region of the Karakoram Range. Study focus: Karakoram is a region in High Mountain Asia with many surge-type glaciers. This study employed over 200 high-temporal-resolution remote sensing images and investigated the variations in elevation and velocity of the Ghujerab River Head Glacier (GRHG) from 2019 to 2023. Furthermore, we elucidated the potential controlling mechanisms. New hydrological insights for the region: Our findings revealed that the GRHG, akin to typical surgetype glaciers in Karakoram, started to surge in the spring and finished surging in the summer, with a duration of less than two years. Throughout the surging process, the glacier transferred a mass of 0.11 +/- 0.003 km3 from the reservoir area to the receiving area, resulting in a thickening of 91.59 +/- 1.04 m at the glacier terminus and thinning of 11.78 +/- 1.04 m in the upper glacier. By analysing the mass balance and glacier surface albedo during surging, we proposed that climatic disturbances in the glacier region provided essential material inputs for the surge. Additionally, based on the seasonal evolution pattern of glacier flow velocity, we inferred a close correlation between surging and variations in subglacial hydrology. The duration of acceleration and deceleration during glacier surging, as well as a comparison with existing studies, further support our conclusion. Future research integrating multi-source remote sensing and onsite observations can support numerical simulations to quantitatively reveal the key processes occurring beneath and within glaciers during surge events.

Glacier velocity is a crucial parameter in understanding glacier dynamics and mass balance, especially in response to climate change. Despite numerous studies on glaciers in the West Kunlun Mts., there is still insufficient knowledge about the details of inter- and intra-annual velocity changes under global warming. This study analyzed the glacier velocity changes in the West Kunlun Mts. using Sentinel-1A satellite data. Our results revealed that: (1) The velocity of glaciers across the region shows an increasing trend from 2014 to 2023. (2) Five glaciers were found to have been surged during the study period, among which two of them were not reported before. (3) The surges in the study region were potentially controlled through a combination of hydrological and thermal mechanisms. (4) The glacier N2, Duofeng Glacier, and b2 of Kunlun Glacier exhibit higher annual velocities (32.82 m a-1) compared to surging glaciers in quiescent phases (13.22 m a-1), and were speculated as advancing or fast-flowing glaciers.

The Vanj River Basin contains a dynamic glacier, the Medvezhiy glacier, which occasionally poses a danger to local residents due to its surging, flooding, and frequent blockages of the Abdukahor River, leading to intense glacial lake outburst floods (GLOF). This study offers a new perspective on the quantitative assessment of glacier surface velocities and associated lake changes during six surges from 1968 to 2023 by using time-series imagery (Corona, Hexagon, Landsat), SRTM elevation maps, ITS_LIVE, unmanned aerial vehicles, local climate, and glacier surface elevation changes. Six turbulent periods (1968, 1973, 1977, 1989-1990, 2001, and 2011) were investigated, each lasting three years within a 10-11-year cycle. During inactive phases, a reduction in the thickness of the glacier tongue in the ablation zone occurred. During a surge in 2011, the flow accelerated, creating an ice dam and conditions for GLOF. Using these datasets, we reconstructed the process of the Medvezhiy glacier surge with high detail and identified a clear signal of uplift in the surface above the lower glacier tongue as well as a uniform increase in velocities associated with the onset of the surge. The increased activity of the Medvezhiy glacier and seasonal fluctuations in surface runoff are closely linked to climatic factors throughout the surge phase, and recent UAV observations indicate the absence of GLOFs in the glacier's channel. Comprehending the processes of glacier movements and related changes at a regional level is crucial for implementing more proactive measures and identifying appropriate strategies for mitigation.