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Surface exposure–age dating was applied to rock surfaces associated with ice‐marginal moraines at elevations of ~1520–1780 m a.s.l. on the slopes of Galdhøpiggen and Glittertinden, the two highest mountains in Scandinavia located in the Jotunheimen mountains of central southern Norway. This is important for understanding the pattern and timing of wastage of the Scandinavian Ice Sheet at the Younger Dryas–Holocene transition. Cosmogenic exposure dating (here 10Be dating) of boulders from the moraine ridges yielded overall mean ages (corrected for glacio‐isostatic uplift, surface erosion and snow shielding) of ~11.6 ka from Galdhøpiggen and ~11.2 ka from Glittertinden. Similar 10Be ages were also obtained from additionally collected proximal and distal erratic boulders and bedrock samples. These enabled age calibration of Schmidt‐hammer R‐values and independent Schmidt‐hammer exposure‐age dating (SHD) of the moraine ridges, which yielded comparable mean SHD ages of ~10.8 and ~10.6 ka from the Galdhøpiggen and Glittertinden sites, respectively. Taking account of the age resolution and other limitations of both dating techniques, the results suggest that the two sets of moraines have approximately the same age but that neither technique can distinguish unambiguously between moraine formation in the late Younger Dryas or Early Holocene. Together with features of moraine‐ridge morphology and estimates of equilibrium‐line altitude depression of ~360–575 m (corrected for land uplift), the results imply moraine formation during short‐lived re‐advances of active glaciers, at least the lower reaches of which were warm‐based. It is concluded that the local glaciers remained active and advanced during deglaciation either very late in the Younger Dryas or very early in the Holocene, possibly in response to the Preboreal Oscillation at ~11.4 ka. The study supports the concept of a thin Younger Dryas ice sheet and places time constraints on the timing of final deglaciation in southern Norway. [ABSTRACT FROM AUTHOR]

The Jostedalsbreen is the largest ice cap in Norway and mainland Europe. Rapid retreat of many of its outlet glaciers since the 2000s has led to the formation of several glacial lakes. Processes causing the formation and expansion of glacial lakes and their interaction with a glacier and terminal moraine have not been widely addressed yet. In this study, we investigate the degradation of the front of the southeast‐facing outlet glacier Austerdalsbreen. Based on a variety of remotely sensed data (UAV‐based and airborne orthophotos and DEMs, satellite images), we analyze the coincident glacial and proglacial changes of Austerdalsbreen and quantify the evolution of this transition zone during the last decades. In particular, we focus on the short‐term evolution of the glacial lake since 2010, we examine the context of a glacier advance in the 1990s, and we report long‐term changes by utilizing 1960s imagery. We discuss the evolution and conditions of Austerdalsbreen compared to other outlet glaciers of Jostedalsbreen. Overall, the glacier terminus has experienced a recession in the last decades. The 1990s terminus advance was more restricted than at other nearby outlet glaciers due to glacier surface debris cover, which is a critical factor for the glacier and lake evolution. However, in the most recent period, since 2012, a distinct expansion of a glacial lake is quantifiable. Since the rates of glacier surface lowering also considerably increased since approximately 2017 and the glacier retreated since the beginning of the 2000s with a clear maximum length decrease in 2015, we interpret the recently formed glacial lake as a contributory factor of glacial changes. [ABSTRACT FROM AUTHOR]

This study presents the sedimentary succession of an outwash plain and an alluvial fan located along the valley Langedalen at the south‐eastern side of the Jostedalsbreen ice cap in inner Sogn, western Norway. A newly exposed ~2.8‐m‐high section along the southern riverbank of Langedøla river shows alternating layers of minerogenic sediments and peat layers with tree logs, identified as Salix sp. The section is situated in the distal part of an alluvial fan built out from the southern slope of Langedalen. Six AMS radiocarbon dates of tree fragments indicate that the accumulation of the fine‐grained sediments in the lower part of the section was initiated earlier than the basal radiocarbon date of 914–976 calibrated years CE (1σ age range). These basal, fine‐grained sediments are interpreted as proglacial outwash deposited in a floodplain depression or abandoned river channel in a low‐energy glaciofluvial environment. Periods of low glacier cover, low river discharge or low‐water stands over the floodplain allowed peat formation and the growth of trees and shrubs in the valley. The radiocarbon dates further indicate relatively rapid sediment accretion (~2.7–3 cm a−1) between 190 and 125 cm below the sediment surface, equivalent to approximately 1220 to 1250 cal. a CE (1σ age range). At ~60 cm depth below the surface, dated to approximately 1590 to 1620 cal. a CE (1σ age range), a transition to more coarse‐grained, sandy and gravelly sediments indicates increased sediment supply and distal expansion of the alluvial fan. This occurred most likely as a consequence of increased sediment yield from expanding glaciers along the southern valley side of Langedalen as a response to the initial Little Ice Age glacier growth. Based on these results, the accretion and progradation of glacier‐fed alluvial fans mainly occur during periods of glacier advance rather than during glacier recession. [ABSTRACT FROM AUTHOR]

Norway is located in an intraplate setting with low-to-moderate seismicity. The mountainous landscape leads to a high level of landside activity throughout the country. Earthquake-induced landslides (EQILs) are common in seismically active areas, but there are only a few studies of EQILs in intraplate regions. We systematically analyse all earthquakes in Norway with magnitudes ≥ 4.5 in the time period 1800–2021 CE. For each event we search for reports of EQILs in the available macroseismic data and in the Norwegian landslide database. We furthermore consider precipitation data from the Norwegian Centre for Climate Services to evaluate the role of precipitation in the triggering of the identified potential EQILs. Through this approach, we identify 22 EQILs that have been triggered by eight earthquakes in the magnitude range 4.5–5.9. The events are widely distributed in northern and southern Norway. The maximum landslide distance limits and landslide-affected areas are much larger than those found in empirical studies of global datasets and are in agreement with data from other intraplate regions. For four of the earthquakes, it seems that landslide triggering was due to a combined effect of precipitation and earthquake ground shaking. Our observations confirm that intraplate earthquakes have the potential to trigger EQILs over large distances, most likely due to the low ground motion attenuation in such regions. Slope susceptibility seems to be another important factor in the triggering. Our conclusions demonstrate the importance of considering EQIL potential in earthquake risk management in intraplate regions. [ABSTRACT FROM AUTHOR]

When Ötzi, the Iceman, was found in a gully in the Tisenjoch pass in the Tyrolean Alps in 1991, he was a huge surprise for the archaeological community. The lead initial investigator of the find argued that it was unique, preserved by serendipitous circumstances. It was hypothesised that the mummy with associated artefacts had been quickly covered by glacier ice and stayed buried until the melt-out in 1991. It is now more than 30 years since Ötzi appeared. In this paper, we take a closer look at how the find can be understood today, benefitting from increased knowledge gained from more than two decades of investigations of other glacial archaeological sites, and from previous palaeo-biological investigations of the find assemblage. In the light of radiocarbon dates from the gully and new glaciological evidence regarding mass balance, it is likely that Ötzi was not permanently buried in ice immediately after his death, but that the gully where he lay was repeatedly exposed over the next 1500 years. We discuss the nature of the ice covering the site, which is commonly described as a basally sliding glacier. Based on the available evidence, this ice is better understood as a non-moving, stationary field of snow and ice, frozen to the bedrock. The damaged artefacts found with Ötzi were probably broken by typical postdepositional processes on glacial archaeological sites, and not, as previously claimed, during conflict prior to Ötzi's flight from the valley below. [ABSTRACT FROM AUTHOR]

Norway is located in an intraplate setting with low to moderate seismicity. The mountainous landscape leads to a high level of landside activity throughout the country. Earthquake-induced landslides (EQIL) are common in seismically active areas, but there are only few studies of EQIL in intraplate regions. We systematically analyse all earthquakes in Norway with magnitudes ≥ 4.5 in the time period 1800-2021 CE. For each event we search for reports of EQIL in the available macroseismic data and in the Norwegian landslide database. We furthermore consider precipitation data from the Norwegian Climate Service Centre to evaluate the role of precipitation in the triggering of the identified potential EQIL. Through this approach, we identified 22 EQIL that have been triggered by 8 earthquakes in the magnitude range 4.5 - 5.9. The events are widely distributed in northern and southern Norway. The maximum landslide distance limits and landslide- affected areas are much larger than those found in empirical studies of global datasets, and in agreement with data from other intraplate regions. For three of the earthquakes, it seems that landslide triggering was due to a combined effect of precipitation and earthquake ground shaking. Our observations confirm that intraplate earthquakes have potential to trigger EQIL over large distances, most likely due to the low ground motion attenuation in such regions. Slope susceptibility seems to be another important factor in the triggering. Our conclusions demonstrate the importance of considering EQIL potential in earthquake risk management in intraplate regions. [ABSTRACT FROM AUTHOR]