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Understanding changes in runoff due to climate variations in glacier-dominated headwaters is key to managing water resources and dryland watersheds effectively and rationally. The continuous glacier shrinkage caused by climate warming has significantly impacted the water supply and ecological systems in the vast arid regions of Central Asia, attracting extensive public concern. The study results indicate an increase in total runoff at the Urumqi River source region during both the baseline (1997–2016) and mid-century (2040–2059) periods, encompassing rain, glacier meltwater, and snowmelt components. Compared to the baseline period, the temperature increases by the mid-century under the three climate scenarios (SSP1−26, SSP2−45, and SSP5−85) range from 0.98 to 1.48 °C. In this region, during the period from 1997 to 2016, glacier meltwater was the dominant component of runoff, comprising 42.10–43.79% of the total, followed by snowmelt at 29.64–30.40% and rainfall contributions of 26.56–27.49%. Additionally, glacier storage in this typical catchment responds quickly to temperature fluctuations, significantly impacting runoff. The Urumqi River source region's runoff exhibits heightened sensitivity to these temperature shifts compared to precipitation effects. We hypothesized three glacier coverage scenarios: unchanged at 100% glaciation, reduced by half to 50%, and fully retreated to 0% glaciation. Analysis of these scenarios demonstrated that glaciers are pivotal in runoff formation. Under the SSP1−26, SSP2−45, and SSP5−85 climate scenarios, glaciers contributed additional runoff increases of 51.61%, 57.64%, and 62.07%, respectively. Generally, glaciers play a critical role in supplying water in dry areas. Thus, accurately forecasting future water resource shifts in high-altitude glacier regions is crucial for downstream water resource management and utilization. [ABSTRACT FROM AUTHOR]

Global warming is causing melting of glaciers, which is affecting socioeconomic development. It is essential to study the combined influence of changes in structures of glaciers on human well-being and socioeconomic systems. Herein, we considered Qilian Mountains as an example, quantified the regional socioeconomic benefits of glaciers and human well-being, and attempted to draw a correlation between glacier service value and human well-being. The findings of our study reveal that the value of glacier services in Qilian Mountains decreased from 1.84 × 1010 yuan in 1998 to 1.72 × 1010 yuan in 2018, with a spatial trend of circling down from the central region to the western and eastern regions. The distribution of human well-being showed an increasing trend, and a phenomenon of "low value central and western clustering, high value eastern sporadic distribution." There is an increasing degree of coordination between human well-being and glacier services value; the spatial distribution shows a decreasing trend from the west to the east, with differences in the nature of coordinated development in different regions at the same coordination stage being obvious. We analyzed the changes in glacier services value and their relationship with human well-being from both micro and macro perspectives to provide theoretical support for formulating management strategies for glacier resource conservation and improving the interface between glacier service evaluation results and government decision-making. [ABSTRACT FROM AUTHOR]

Global warming has accelerated during the past decades, causing a dramatic shrinking of glaciers across the globe. So far, the attempts to counterbalance glacial melt have proven to be inadequate and are mostly limited to a few glacial landscapes only. In the present study, a scientific glacier protection experiment was conducted at the Dagu Glacier site. Specifically, the study site was the Dagu Glacier No. 17, situated 4830 m a.s.l. The study involved a deliberate verification of the feasibility and effectiveness of using geotextile covers on small glaciers located at high altitudes between August 2020 and October 2021. The observations revealed that the mass loss in the area covered with geotextiles was, on average, 15% lower (per year) compared to that in the uncovered areas combining field campaigns, terrestrial laser scanning, and unmanned aerial vehicle. The reason for this could be that the albedo of the geotextile is higher than that of the glacier surface. In addition, the aging of geotextiles causes a decline in their albedo, leading to a gradual decline in the effectiveness of the resulting glacier protection. It was indicated that geotextiles could be effective in facilitating the mitigation of glacier ablation, although the cost-related limitations render it difficult to upscale the use of artificial cover. Nonetheless, using active artificial cover could be effective in the case of small glaciers, glacier landscapes, and glacier terminus regions. [ABSTRACT FROM AUTHOR]

The Mt.Tomur glaciers, in the Tian Shan mountains of Western China, are usually debris-covered, and due to climate change, glacial hazards are becoming more frequent in this region. However, no changes in the long-time series of glacier surface velocities have been observed in this region. Conducting field measurements in high-altitude mountains is relatively difficult, and consequently, the dynamics and driving factors are less studied. Here, image-correlation offset tracking using Landsat images was exploited to estimate the glacier surface velocity of glaciers in the Mt.Tomur region from 2000 to 2020 and to assess glacier ice thickness. The results show that the glacier surface velocity in the Mt.Tomur region showed a significant slowdown during 2000–2020, from 6.71 ± 0.66 m a−1 to 3.95 ± 0.66 m a−1, an overall decrease of 41.13%. The maximum glacier ice thickness in the Mt.Tomur region was estimated based on the ice flow principle being 171.27 ± 17.10 m, and the glacier average thickness is 50.00 ± 5.0 m. Glacier thickness at first increases with increasing altitude, showing more than 100 ± 10 m ice thickness between 3400 m and 4300 m, and then decreases with further increases in altitude. The reliability of the surface velocity and ice thickness obtained from remote sensing was proved using the measured surface velocity and ice thickness of Qingbingtan glacier No. 72 stall (the correlation coefficient R2 > 0.85). The debris cover has an overall mitigating effect on the ablation and movement rate of Qingbingtan Glacier No. 72; however, it has an accelerating effect on the ablation and movement rate of glacier No. 74. [ABSTRACT FROM AUTHOR]

This study deploys RTK-GNSS in 2012, TLS in 2015 and UAV in 2018 to monitor the changes of Urumqi Glacier No. 1 (UG1), eastern Tien Shan, and analyzes the feasibility of three technologies in monitoring the mountain glaciers. DEM differencing shows that UG1 has experienced a pronounced thinning and mass loss for the period of 2012–18. The glacier surface elevation change of −0.83 ± 0.57 m w.e. a−1 has been recorded for 2012–15, whereas the changes of glacier tongue surface elevation in 2015–18 and 2012–18 were −2.03 ± 0.95 and −1.34 ± 0.88 m w.e. a−1, respectively. The glacier area shrunk by 0.07 ± 0.07 × 10−3 km2 and the terminus retreat rate was 6.28 ± 0.83 m a−1 during 2012–18. The good agreement between the glaciological and geodetic specific mass-balances is promising, showing the combination of the three technologies is suitable to monitor glacier mass change. We recommend application of the three technologies to assess each other in different locations of the glacier, e.g. RTK-GNSS base stations, ground control points, glacier tongue and terminus, in order to avoid the inherent limitations of each technology and to provide reliable data for the future studies of mountain glacier changes in western China. [ABSTRACT FROM AUTHOR]

The glaciers in the Sawir Mountains are an important freshwater resource, and glaciers have been experiencing a continuing retreat over the past few decades. However, studies on detailed glacier mass changes are currently sparse. Here, we present the high-precision evolution of annual surface elevation and geodetic mass changes in the ablation area of the Muz Taw Glacier (Sawir Mountains, China) over the latest three consecutive mass-balance years (2017–2020) based on multi-temporal terrestrial geodetic surveys. Our results revealed clearly surface lowering and negative geodetic mass changes, and the spatial changing patterns were generally similar for the three periods with the most negative surface lowering (approximately −5.0 to −4.0 m a−1) around the glacier terminus. The gradient of altitudinal elevation changes was commonly steep at the low elevations and gentle in the upper-elevation parts, and reduced surface lowering was observed at the glacier terminus. Resulting emergence velocities ranged from 0.11 to 0.86 m a−1 with pronounced spatial variability, which was mainly controlled by surface slope, ice thickness, and the movement of tributary glaciers. Meanwhile, emergence velocities slightly compensated the surface ablation at the ablation area with a proportion of 14.9%, and dynamic thickening had small contributions to glacier surface evolution. Limited annual precipitation and glacier accumulation may result in these weak contributions. Higher-resolution surveys at the seasonal and monthly scales are required to get insight into the mass balance processes and their mechanism. [ABSTRACT FROM AUTHOR]