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Glaciers and ice caps in Norway are presently undergoing mass loss, areal reduction, and frontal retreat, mainly a result of increased summer ablation due to rising summer temperatures over Scandinavia, especially after 2000 CE. In this paper, the glacier mass-balance response of 10 Norwegian glaciers with continuous mass balance observations (>10 years) to climate projections from 1971–2000 to 2071–2100 have been estimated. Projected changes in mean summer temperature and mean winter precipitation from 1971–2000 to 2071–2100, applying the RCP8.5 emission scenario for five different regions in Norway; 'Sogn og Fjordane' and 'Hordaland', now Vestland County in western Norway, 'Oppland', now part of Innlandet County in eastern Norway, and Nordland County and Finnmark County, both in Northern Norway), range between +3.5°C and +5.0°C, and between +5% and +25%, respectively. These climate projections have been converted (by linear regression with overlapping observational mass-balance data) into specific surface glacier mass balance [winter balance (B w), summer balance (B s), and annual balance (B a) for 10 glaciers in Norway with mass-balance series [Ålfotbreen, Nigardsbreen (part of Jostedalsbreen), Austdalsbreen (part of Jostedalsbreen), Rembesdalskåka (part of Hardangerjøkulen), Blomstølskardsbreen (part of Søre Folgefonna), Storbrean, Hellstugubrean, Gråsubrean, Engabreen (part of Vestre Svartisen, Langfjordjøkelen (data: http://glacier.nve.no/glacier/viewer/ci/no/) yielding a total, cumulative surface glacier mass loss from 2000 to 2100 CE in the range of -85.2 ± 4 to -197.3 ± 10 m water equivalents. The estimated changes in equilibrium-line altitudes (ELAs), in the range of 230 ± 10 to 630 ± 30 m, indicate that the mean ELA may reach the upper part of 7 of the 10 glaciers included in this study [Ålfotbreen, Austdalsbreen, Rembesdalskåka, Blomstølskardsbreen, Gråsubrean, Engabreen and Langfjordjøkelen] by the end of the 21st century. The projected glacier mass loss and ELA rise, and thus changes in glacier length, area and volume, will most likely have profound consequences for future glacier hydrology (runoff), hydropower production, wildlife, ecosystems, glacier hazards, and tourism. [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]

Srivastava and Jovane (2020) have made several comments on our assessment of proxy data and challenged the outcome of Shukla et al. (2020) based mainly on interpretation of environmental magnetic parameters. We respond to their criticisms and re-evaluate our paper, remove ambiguities and validate our conclusions through additional proxies (grain-size and geochemistry). We welcome their comments and do not entirely rule out their interpretation for magnetic mineralogy. We highlight the importance of proxy validation for high-energy environments like Chorabari lake. However, single proxy data correlation is likely to produce biased results with no relevant meaning. The objective of our study was to understand complexities in the glacial-climate system by reconstructing late-Holocene climate variations using the glacial lake sediment records from the Mandakini River Basin, Central Himalaya, India. We presented the complexities in Shukla et al. (2020), and this was also highlighted by Srivastava and Jovane (2020). In response, we provide additional justification of proxy response and substantiate our results with present-day estimates from the Chorabari glacier valley. We disagree with the thesis put forward by Srivastava and Jovane (2020) in their conclusion as they overemphasize the interpretation of a single proxy. We maintain that the investigation of present-day glacial settings is an important precursor of paleoclimatic data interpretation and that this supports our conclusions. We will try to incorporate the important suggestions of Srivastava and Jovne (2020) relating to the interpretation of magnetic data in future work. [ABSTRACT FROM AUTHOR]

Shukla et al. explored paleoclimatic signals from a ~8 m thick profile of a moraine-dammed lake in the central Himalaya exposed due to lake burst from a flash flood in 2013. The main objective of their research work is to understand the complex glacial-climate system during late-Holocene. They attempted a novel multi proxy approach for paleoclimate reconstruction but their work suffers from misinterpretation of various proxies and erroneous/misleading discussion. We therefore report following major points in this comment article. (1) Misinterpretation of magnetic parameters : Magnetic susceptibility (χlf) has been used to interpret changes in magnetic mineralogy rather than concentration of magnetic minerals. Susceptibility of anhysteretic remanence (χARM) has been used at several places to indicate presence of superparamagnetic (SP) and multi domain (MD) ferrimagnetic particles rather than single domain (SD) ferrimagnetic (magnetite) particles. Interpreting erroneous negative values of percentage of frequency dependent susceptibility (χfd%) for climate change. (2) Poor chronology : Overlaps in ages of glacial-lake sediments. (3) References : Several statements in paper have not been referenced and some of them have out of place citations. (4) Carefree writing : Authors have shown typical example of carefree writing of a research article, for example, giving units to dimensionless parameter S-ratio, and χfd%, differences in units of χ lf in text and figure, different depths for the same age in text and figure. (5) Over interpretation : Authors at places have interpreted climatic variations based on only one sample. (6) Poor justifications : Authors did not provide any detailed justification for proxy data while interpreting climatic variations. (7) No data (results) on mineralogy and trace elements were given. Overall it is not only a problem of presentation and misinterpretation of proxy data but the study also fails to deliver the final message of climate change and glacier dynamics in the central Himalaya. [ABSTRACT FROM AUTHOR]

A warming climate is melting the namesake glaciers of Glacier National Park, Montana, USA. James Dyson’s 1948 paper was one of the earliest publications to emphasize climate change impacts to the cryosphere through an examination of Sperry and Grinnell Glaciers. This paper, combined with his subsequent works, acts as a pillar for current glacier monitoring efforts. [ABSTRACT FROM AUTHOR]