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Dań Zhùr (Donjek) Glacier is a surge-type glacier that undergoes cyclical periods of rapid advance over ∼1–2 years, followed by retreat for ∼10 years. Since the 1990s, the advances have caused the formation of ice-dammed Dań Zhùr Lake, which has filled and drained in summers following a surge event. Here, we report how these drainages initially occur through a subglacial channel under the glacier terminus, which then typically closes the following winter, enabling another lake to form and drain the next summer. However, our remote sensing and field observations indicate that after several drainage events, a subaerial ice canyon is formed through the glacier terminus, which prevents another lake from forming until after the glacier surges again. We predict that the next surge of Dań Zhùr Glacier will occur around the mid-2020s, causing the formation of a larger Dań Zhùr Lake during the following quiescent phase because, despite periodic advances, a long-term trend of glacier recession is exposing a larger basin for the lake to form in. However, each subsequent surge is causing less terminus advance than the previous one, until ultimately the surges will be insufficient to dam Dań Zhùr Chù’ (Donjek River), and lakes will cease to form.

Glacier surges can create ice-dammed lakes when the advancing terminus blocks drainage. Such lakes are inherently unstable and can drain abruptly as glacial lake outburst floods (GLOFs), presenting a hazard to downstream populations and infrastructure in high mountain environments. We present satellite image analysis of the evolution of an ice-dammed lake formed by the 2018–20 surge of Shisper Glacier, western Karakoram. Our analysis identifies six phases of lake evolution. A large lake of up to 33.7 ± 9% million m3 formed in 2018–19, 2019–20, 2020–21 and 2021–22. In each case, the lake began to fill late in the year, reached a maximum size in May, and had completely drained between May and July, typically over 1–2 days. This analysis provides further evidence that GLOF hazards associated with lakes dammed by glacier surges can persist for several years after surge termination.

Lake-terminating glaciers have some peculiar behaviors compared to land-terminating glaciers, but in-depth observation is still limited regarding their formation, which is crucial for understanding the glacier–lake interaction. Here, the long-term evolutions of Tanymas Lake and the Fedchenko Glacier were investigated based on Landsat images, Google Earth imagery, KH-9 images, glacier surface elevation and velocity change datasets, and meteorological records. The results indicate that Tanymas Lake is both an ice-contact proglacial lake and an ice-dammed lake. It covered an area of 1.10 km2 in September 2022, and it is one of the largest glacial lakes in Pamir and even in HMA. The initial basin of Tanymas Lake is a moraine depression in Tanymas Pass, and the blocked dam is the Tanymas-5 Glacier and its terminal moraine. Tanymas Lake was in an embryonic stage before August 2005, in a formation and expansion stage from August 2005 to September 2018, and in a new expansion stage after September 2018. In this process, the Tanymas terminus of the Fedchenko Glacier also transformed from a land terminus to a partial lake terminus, and then to a complete lake terminus. The formation of Tanymas Lake is associated with the accumulation of glacial meltwater and the blockage of drainage, while the slow expansion of Tanymas Lake is related to the cold climate and slight glacier mass loss of Central Pamir. In the coming decades, with the accelerated mass loss of the Tanymas terminus of the Fedchenko Glacier, the area, depth, and water storage of Tanymas Lake will continue to increase, accompanied by the growing GLOF risk. [ABSTRACT FROM AUTHOR]

The Siljan region hosts Europe's largest impact structure. The high‐relief landscape, with a central granite dome bordered by lake basins, contains an array of glacial and shore‐level landforms. We investigated its deglaciation history by mapping and analysing landforms on high resolution LiDAR (light detection and ranging)‐based digital surface models coupled with well‐dated sediment successions from peat and lake sediment cores. The granite dome and bordering areas are characterized by streamlined terrain and ribbed moraine with a streamlined overprint. These suggest an ice‐flow direction from north‐northwest (NNW) with wet‐based thermal conditions prior to deglaciation. During its retreat, the ice sheet was split into thinner plateau ice and thicker basin ice. Sets of low‐gradient glaciofluvial erosion channels suggest intense ice‐lateral meltwater drainage across gradually ice‐freed slopes, while 'down‐the‐slope' erosion channels and eskers show meltwater drainage from stagnated plateau ice. Thick basin ice receded with a subaqueous margin across the deep Siljan–Orsasjön Basin c. 10,700–10,500 cal. bp. During ice recession the ingression of the Baltic Ancylus Lake led to diachronous formation of highest shoreline marks, from ~207 m in the south to ~220 m above sea level (a.s.l.) in the north. Differential uplift resulted in shallowing of the water body, which led to the isolation of the Siljan–Orsasjön Basin from the Baltic Basin at c. 9800 cal. bp. The post‐isolation water body – the 'Ancient Lake Siljan' – was drained through the ancient Åkerö Channel with a water level at 168–169 m a.s.l. during c. 1000 years. A later rerouting of the outlet to the present course was initiated at c. 8800 cal. bp, which led to a lake‐level lowering of 6–7 m to today's level of Lake Siljan (~162 m a.s.l.). This study shows the strength of an integrated methodological approach for deciphering the evolution of a complex landscape, combining highly resolved geomorphological analysis with well‐dated sediment successions. [ABSTRACT FROM AUTHOR]

A proglacial lake system formed during the Late Valdai (Weichselian) Ice Sheet recession on the East European Plain. Poor knowledge about chronology, levels and the drainage pathways of ice‐dammed lakes does not allow us to fully evaluate their palaeogeographic significance. This study focuses on the Izborsko‐Malskaya Valley where fingerprints of a glaciolacustrine environment were found. Based on litho‐, biostratigraphic and geochronological data, it is estimated that the proglacial lake in the Izborsko‐Malskaya Valley existed from ~14.3 ka cal. BP (the Vashinogorskaya Valley from ~14.9 ka (optically stimulated luminescence)) to 13.2 ka cal. BP. The maximum level was ~72 m a.s.l. (above sea level) and the minimum was ~53 m a.s.l. Sedimentation proceeded mostly in deepwater conditions. The ice‐dammed lake in the Izborsko‐Malskaya and nearest valleys could have been part of a huge lake on the Pskov lowland which formed after ~15.7 ka cal. BP. The lake level dropped rapidly when the proglacial Lake Pskovsko‐Chudskoe (Peipsi) connected with the Baltic Ice Lake. A lacustrine regime was preserved only in the southern portion of the Izborsko‐Malskaya Valley after drainage and still exists in the modern lakes. The presented approaches to the ice‐dammed lake reconstruction could be useful for the verification of other lakes which existed on the East European Plain. [ABSTRACT FROM AUTHOR]

Hydro‐acoustic and seismic data and 2‐ to 16‐m‐long sediment cores from the central area of Lake Taymyr (Taymyr Peninsula, central Russian Arctic) were investigated to reconstruct its sedimentation history. Granulometric, chronological, geochemical and biological data from the sediment cores reveal two lowstands and two highstands of the lake level, which is today located ca. 5 m above sea level during summer. Our study confirms the presence of an ice sheet blocking the drainage of Lake Taymyr during the latest Weichselian. Although chronological control of the sediment cores does not allow us to unambiguously constrain the time frame for each of the lake stages, the proposed timing of events is in good agreement with regional terrestrial archives as well as marine signals on the Kara Sea Shelf. Overall, the data show that the evolution of Lake Taymyr involved a complex interplay of regional climatic, glacial and sea‐level changes. [ABSTRACT FROM AUTHOR]

The thinning and final decay of the Scandinavian Ice Sheet in the Gudbrandsdalen area in central southern Norway is described, based on (1) cosmogenic 10Be surface exposure dating of 25 glacially transported boulders, (2) radiocarbon dating of plant remains in the basal strata in four lakes and (3) mapping of large ice-dammed lakes that formed at different elevations and at different times during the last deglacation. We complement the new chronology with previously published 10Be-ages from the same region. The dated samples are spread from mountain summits 1800 m a.s.l. to the valley floor at 250 m a.s.l. Our results suggest that the ice sheet surface remained well above 1800 m a.s.l. in northern Gudbrandsdalen throughout the Younger Dryas. During the Early Holocene the ice sheet thinned rapidly, at rates estimated to 1.7–5.8 m yr−1. The final phase of deglaciation involved formation of large ice-dammed lakes, most notably the Store Dølasjø which was formed after 10.4 ka BP and finally drained around 10.0 ka BP. The ice-marginal landforms that characterize the mountain region of northern Gudbrandsdalen, i.e., moraine ridges, lateral meltwater channels, as well as deposits and shorelines from ice-dammed lakes, thus collectively originate from a period of rapid ice sheet downwasting over ca. 1600 years. • Three independent methods used to reconstruct deglaciation in southern Norway. • Ice-dammed lakes, 10Be-dating of boulders and radiocarbon dated lake records. • Thinning rates for the Scandinavian Ice Sheet based on empirical data. • New reconstruction and dating of the Store Dølasjø ice-dammed lake. • Important constraints for ice sheet models and eustatic sea level budgets. [ABSTRACT FROM AUTHOR]