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A great deal of research has been conducted in the mountains; however, most of the scientific information remains scattered with minimal use in the policy and governance. We systematically reviewed and evaluated the published scientific literature on the Himalaya and identified 77,912 research outputs from 12,258 sources. Agriculture and Biological Sciences was dominant field of research followed by Earth Sciences, Medicine, Environmental Sciences and Social Sciences. Number of publications has increased annually in the Himalaya in all research disciplines, especially after 2000 with highest funding from India, China, and USA whereas highest scientific contribution from India, Nepal, USA, UK, and China. In terms of research quality, nearly 45 % of the research papers were published in SCI indexed journals. Cumulative impact factor of research articles has increased consistently whereas average impact factor was higher during 1970–1990. Prominent research themes in the Himalaya includes humans, clinical studies, animalia, genetics, risk assessment, healthcare, tectonics, climate change, earthquakes, rainfall, biodiversity, glaciers etc. Research publications in the Himalaya covers a wide range of aspects like field-based data driven studies, new discoveries and observations, application of new methods and techniques, application of theoretical knowledge, policy, governance etc. The Himalaya which is often termed as a data deficient region is a repository for large volume of scientific and socio-cultural information. This information if curated carefully under a uniform and multidisciplinary framework involving a trans-boundary network of Himalayan nations will provide a powerful tool for evidence-based policies and practice to address emerging environmental challenges in the region. • The Himalaya constitutes the highest and one of the largest mountain ecosystem on the earth. • Bioscience is the dominant field of research followed Geology, Medicine, and Environmental Science. • India, China, USA, and Nepal are the largest contributors in scientific output and funding. • Volume and quality of scientific publications has increased particularly after 2000 in all research themes. • If curated carefully, this information will provide a powerful tool for evidence-based policies and practice. [ABSTRACT FROM AUTHOR]

In High Mountain Asia, human-induced climate warming threatens the cryosphere. Expected long-term reductions in future runoff from glacial catchments raises concerns regarding the sustainability of these natural 'water towers' and the implications of reduced water availability for regional human and ecological systems. Ice-debris landforms (I-DL), containing ice whether moving or not include rock glaciers and ice-cored moraines, and are likely to be climatically more resilient than debris-covered and debris-free glaciers. Recent work has shown that rock glaciers contain globally valuable water supplies yet over High Mountain Asia information regarding their number, spatial distribution, morphometric characteristics and water content are scarce. Here, we present the first systematic estimate of the current extent and distribution of rock glaciers for a subset of High Mountain Asia (the Himalaya). A sample of 2070 intact and relict rock glaciers were digitized on Google Earth imagery from the Western, Central and Eastern Himalaya regions and then quantitative and qualitative characteristics were analysed regionally based on topographic data from the NASA Shuttle Radar Topography Mission (SRTM) Version 3.0 and then aggregated across the Himalaya using an "upscaling" method. The majority of the digitized landforms (∼65%) were categorised as intact rock glaciers (i.e., ice-debris Landforms, or I-DLs, containing ice) and the remainder as relict rock glaciers (i.e., discrete debris accumulations or DDAs, not containing ice). They range in elevation from 3225 to 5766 m a.s.l., with the lowest in the Central Himalaya. Sampled relict and intact rock glaciers are primarily situated on northern quadrants. Over the entire Himalaya, we identified ∼25,000 landforms, with a total estimated areal coverage of 3747 km2. The area upscaling method was validated in the Manaslu region of Nepal using high-resolution Planet data (5 m) and freely available, fine spatial resolution optical satellite data accessed through Google Earth Pro and ESRI basemaps. In absence of complete rock glacier inventories over the Himalaya, our approach proves useful to investigate the nature, distribution and infer potential future behaviour of these landforms across the Himalaya in a changing climate. • Climate change in the mountains of the Himalaya is driving glacier melting and associated changes in water supplies to downstream areas. • This impacts the water supplies for hundreds of millions of people and ecosystems and is seen as a great challenge for future sustainable development in this part of central Asia. • However, large volumes of ice are contained are contained in rock glaciers (ice-debris landforms common in high arid mountains) although research on the number and extent of these in the Himalaya is limited. • In this paper, we present the first systematic estimate of the current extent and distribution of rock glaciers for the Himalaya and show that around 25,000 landforms exist in the region, with a total estimated areal coverage of 3747 km2. • We argue that rock glaciers constitute hydrologically valuable long-term water stores and, with continued climatically-driven glacier recession and mass loss, their value is likely to become increasingly important. [ABSTRACT FROM AUTHOR]

Central Yakutia is a large region in northeastern Siberia characterized by extensive permafrost, large river valleys, mountain glaciers, and large massifs of aeolian sands; the geological history of the region is complex and, at present, poorly constrained. In recent years, it has been shown that aeolian sands cover up to 60% of large parts of Central Yakutia. This paper presents the results of luminescence dating of aeolian sedimentation at the Diring Yuriakh Palaeolithic site located in the middle reaches of the Lena River. Field studies identified several thick units of aeolian sand, which cover an old deflation surface with Late (Duktai culture) and Early Palaeolithic (Diring culture) artefacts. The reliability of the OSL chronology was assessed by comparison of ages based on the optically stimulated luminescence from quartz and the infra-red stimulated luminescence from potassium-rich feldspars; these age pairs are in good agreement, implying that at least the quartz grains were sufficiently bleached before sedimentation. We obtained OSL ages that reflect three periods of accumulation between the LGM and the Holocene: ∼21 ka, 15-14 ka, and 12.5–10 ka. These periods of accumulation broadly coincide with global cooling episodes during the Last Glacial Maximum, the Older Dryas, and the Younger Dryas, with some extension into subsequent warmer intervals, whereas the intervening intervals without preserved sediments are taken to reflect dune stability during warmer periods. The sand on the terraces, sourced from alluvial bars in the river channel, was blown up the valley slope during cold and dry periods when the vegetation cover was sparse. When the climate warmed, the vegetation took some time to spread, and so the accumulation of aeolian sand on the high terraces continued into the warm periods. We also infer periods of deflation (wind erosion) that occurred before 21 ka and between 20 and 15 ka, presumably due to increased aeolian activity and localized remobilization of sediment. The new OSL chronology shows that the younger artefacts located at the cape of Diring Yuriakh, belonging to the Late Palaeolithic Duktai culture, are older than 15 ka. The new ages also show that the post-LGM aeolian sand sequences at Diring Yuriakh are correlated with the regionally developed subaerial Dolkuma Formation. [ABSTRACT FROM AUTHOR]

Alpine glaciers and permafrost are sensitive to climate change, and their degradation due to annual temperature increasing has already induced many mass movements such as debris flows. On September 4 of 2007, July 25–31 and September 5–8 of 2010, three large debris flows took place in Tianmo gully, a left-bank tributary of Parlung River, southeast Tibetan Plateau. The debris flows blocked the river, and a section of highway 450 m long including a bridge 76 m long were destroyed by the subsequent outburst flood. This paper, based on post-event investigations, witness accounts, news reports and satellite image interpretation, systematically analyses the geo-environments, climate conditions and sources of these debris flow events. Their differences in flow process, surge numbers and velocity suggest that they resulted from different geohazard processes, cascades and initiation mechanisms. The 2007 debris flow originated from a bare rock/moraine collapse next to the cirque due to strong alternation of wet and dry conditions. The mass moved down the gully with velocity of 30–40 m/s estimated by back-calculation using superelevation and run-up. It entrained moraine, avalanched snow-ice and water from the channel, and transformed into high-speed debris flow, crossing the Parlung River and finally depositing onto the highway. The other two events in July and September of 2010 initiated from two channel-bank landslides triggered by melt-water and concentrated rainfall, which dammed the channel. The subsequent landslide dam failure generated debris flows over several days, with velocities of 12–14 m/s, that temporally blocked Parlung River. The initiation mechanisms of most large debris flows recorded in Parlung region are similar to the events in Tianmo gully, originating either from rock/moraine avalanches or from the collapse of a landslide dam. This implies that the periglacial degradation of bedrock and moraine is the key process to be monitored and assessed under climate warming. The paper applies the geohazard mechanisms and cascade to hazard monitoring in order to protect the existing Sichuan-Tibet highway and the forthcoming railway. [ABSTRACT FROM AUTHOR]

The collapse of glacial, permafrost, and ice-rich moraine slopes in high-altitude mountainous areas not only threatens downstream residents and infrastructure but also displaces ice mass to lower and warmer elevations, accelerating glacial ablation to some extent. Despite being considered rare, ice-rich slopes collapse more frequently than commonly thought due to climate change. For example, two adjacent mountain glaciers in the Aru Range of the Tibetan Plateau, characterized by large volumes (68 × 106 m3 and 83 × 106 m3, respectively) and low surface slope angles (12.3° and 12.9°, respectively), collapsed surprisingly in 2016. While the mechanisms behind these collapses have garnered broad attention, the ability to quantitatively assess the instability of ice-rich slopes remains limited due to the complex interplay of multi-physical processes. Taking the Aru glacier collapses as reference cases, this paper presents a conceptual model, implemented through coupled thermo-hydro-mechanical simulation, to evaluate the stability of high-altitude ice-rich slopes due to climate change, rainfall and ice ablation. Results indicate that the methodology captures the effects of temperature change, rainfall and meltwater on the instability events well, demonstrating promising potential in evaluating potential collapse zones of ice-rich slopes similar to the Aru glaciers. Furthermore, the role of climate change in the well-known Aru events is demonstrated using a state-of-the-art global climate reanalysis dataset. Findings reveal that the increase in liquid water infiltrating the Aru glaciers since 2010 was a critical factor leading to the instability events. • A conceptual model is proposed to analyse the stability and collapse zones of ice-rich slopes. • The modelling elucidates the causes of twin collapses of the Aru glaciers. • Results contribute to ice-rich slope instability prediction and associated disaster risk management. [ABSTRACT FROM AUTHOR]

Mountain glaciers are one of the most sensitive indicators of climate change. Reconstructing past glacier extents provides valuable insights into the climate change for specific regions where instrumental records are not enough and even absent. In the paper we mapped the outlines for 691 Little Ice Age (LIA) glaciers in terms of prominent moraines beyond contemporary glaciers in the Tanggula Mountains, central Tibetan Plateau (TP). Based on these glacier outlines, we reconstructed the ice thicknesses and surfaces for the LIA glaciers in the region. Accordingly, we calculated the equilibrium-line altitudes (ELAs) for contemporary and LIA glaciers. By comparing the ELAs between the contemporary and LIA glaciers, we estimated the LIA summer temperature decreases in different subregions of the Tanggula Mountains. Since the LIA, the ELA have risen by 35.6 ± 18.8 m, 26.1 ± 17.6 m, and 63.1 ± 38.6 m in the respective western, central, and eastern subregions of the Tanggula Mountains. Assuming no change in precipitation, the LIA summer temperature would decrease by 0.22 ± 0.12 °C, 0.14 ± 0.09 °C, and 0.34 ± 0.21 °C in the three subregions, respectively. Moreover, glaciers in the western, central, and eastern subregions have lost 13.3%, 23.9%, and 42.8% of their area, 15.4%, 25.3%, and 39.6% of their length, and 20.8%, 39.0%, and 61.0% of their volume, respectively. By compiling the LIA ELA data from previous studies, we also estimated the LIA summer temperature changes for other regions of the TP. The LIA ELA and summer temperature changes relative to the present showed a decreasing trend from the edges towards the interior on the TP. • LIA glaciers and summer climate were reconstructed at the Tanggula Mountains. • LIA summers were 0.22 ± 0.12 °C, 0.14 ± 0.09 °C, and 0.34 ± 0.21 °C cooler than present in three subregions. • Summer temperature change had a decreasing trend from the edges towards the interior on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Subglacial processes influence the large-scale behaviour of glaciers and determine the geological processes that occur at the ice-substrate interface. In this paper we focus on subglacial deformation beneath a cold-based glacier resting on permafrost. We ask what are the drivers of subglacial permafrost deformation, how is strain distributed beneath glaciers with a permafrost substrate, how is strain transmitted from the glacier into the substrate, and how is deformed permafrost incorporated into the basal zone of the glacier? To address these questions a tunnel excavated in the margin of Wright Lower Glacier in the McMurdo Dry Valleys, Antarctica to observe the structure of the basal zone and bed of the glacier and to monitor basal ice deformation over a period of 4 years. The tunnel revealed a stacked sequence of stratified debris-bearing and clean ice layers, and thick rafts of frozen sediment. Isotopic and gas analyses reveal that despite the low local temperature of the basal ice (−18.5 °C), liquid water has played an important role in the formation of this basal sequence. The rafts of frozen sediment contain well preserved sedimentary structures and algae layers that show the material has been entrained from the underlying permafrost. Deformation measurements made with a combination of displacement transducers, strain arrays, and plumb-lines show that strain and motion within the basal zone are heterogeneous and that strain is transmitted through the permafrozen sediment and into intra-sediment ice layers. The distribution of strain in the basal zone produces a compound velocity profile resembling the deformation patterns inferred from deformation structures in Pleistocene permafrost and also resembles profiles associated with subglacial sediment deformation driven by hydrogeological processes. We conclude that ice-rich permafrost is readily deformed by glaciers and that there is no clear boundary between basal ice and deforming permafrost. [ABSTRACT FROM AUTHOR]

In mountainous regions, climate change threatens cryospheric water resources, and understanding all components of the hydrological cycle is necessary for effective water resource management. Rock glaciers are climatically more resilient than glaciers and contain potentially hydrologically valuable ice volumes, and yet have received less attention, even though rock glacier hydrological importance may increase under future climate warming. In synthesising data from a range of global studies, we provide the first comprehensive evaluation of the hydrological role played by rock glaciers. We evaluate hydrological significance over a range of temporal and spatial scales, alongside the complex multiple hydrological processes with which rock glaciers can interact diurnally, seasonally, annually, decadally and both at local and regional extents. We report that although no global-extent, complete inventory for rock glaciers exists currently, recent research efforts have greatly elaborated spatial coverage. Using these research papers, we synthesise information on rock glacier spatial distribution, morphometric characteristics, surface and subsurface features, ice-storage and hydrological flow dynamics, water chemistry, and future resilience, from which we provide the first comprehensive evaluation of their hydrological contribution. We identify and discuss long-, intermediate- and short-term timescales for rock glacier storage, allowing a more balanced assessment of the contrasting perspectives regarding the relative significance of rock glacier-derived hydrological contributions compared to other water sources. We show that further empirical observations are required to gain a deeper hydrological understanding of rock glaciers, in terms of (i) their genesis and geomorphological dynamics (ii) total ice/water volume; (iii) water discharge; and (iv) water quality. Lastly, we hypothesise that at decadal and longer timescales, under future climate warming, degradation of ice within rock glaciers may represent an increasing hydrological contribution to downstream regions, and thus increased hydrological significance while rock glacier water stores persist. [ABSTRACT FROM AUTHOR]

Proglacial lakes can affect the stability of mountain glaciers and can partly disengage glacier behaviour from climatic perturbations. However, their role in controlling the onset and progression of deglaciation from the Last Glacial Maximum (LGM) remains poorly understood. This lack of understanding is partly because the evidence required to consistently and robustly identify the location and evolution of ice-contact lakes is not standardised. In this paper we therefore firstly present a new set of criteria for identifying the landform and sedimentary evidence that defines and characterises ice-marginal lakes. Secondly, we then apply these key criteria with the aid of high-resolution topographic mapping to produce the first holistic definition and assessment of major proglacial lake landforms and sediments pertaining to the end of the LGM across South Island, New Zealand. The major findings of this assessment can be grouped to include that: (i) The localised constraints to proglacial lake extent were topography, glacier size and meltwater/sediment fluxes, (ii) Lake damming was initiated by outwash fan-heads that interrupted water and sediment flows down-valley, and (iii) New Zealand LGM lakes were unequivocally in contact with a calving ice margin. These findings will be useful for reconstructing ice dynamics and landscape evolution in this region. • Key criteria to identify, characterise and interpret landforms and sediments associated with ice-contact proglacial lakes. • Exploitation of high-resolution LiDAR topographic data for proglacial lakes across South Island, New Zealand. • Synthesis analysis of the 3D geometry, landforms and sediments, and interpretation of the evolution of New Zealand LGM lakes. [ABSTRACT FROM AUTHOR]

In recent years, increasing moisture over the Arctic and subarctic regions shows that the Arctic is experiencing wetting conditions, and poleward atmospheric moisture transport (PAMT) plays a vital role in the atmosphere-ice/snow interactions in the Arctic. To identify the effect of PAMT on the surface energy balance (SEB) for the Arctic glacier, meteorological data from an automatic weather station (AWS) at 377 m a.s.l. on the Austre Lovénbreen glacier, as well as the ERA5 reanalysis data from 30 April 2014 to 30 April 2015, were analyzed in this paper. Our results show that the net shortwave radiation (S net) (18 W m−2, 55%), turbulent sensible (H) (14 W m−2, 43%) and subsurface heat flux (G) (1 W m−2, 2%) act as the energy sources, while the net longwave radiation (L net) (−19 W m−2, 56%), melt energy (Q m) (−12 W m−2, 35%) and turbulent latent heat flux (LE) (−3 W m−2, 9%) represent the heat sink. The development process of Atmospheric River (AR), primary form of PAMT, near the Svalbard in February 2015 was revealed according to the total column water vapor, 850 hPa winds and geopotential height fields. Compared to summer, the glacier SEB was more affected in winter by PAMT, leading to a frequent overcast and thus increasing air temperature, moisture, and wind speed, all of which are variables governing the SEB by decreasing H, LE and G less than increasing the L net. Our findings obtained here can help to better understand the diverse SEB change on the high Arctic glacier from the perspective of PAMT and large-scale atmospheric circulations anomalies. [ABSTRACT FROM AUTHOR]

Climate models and ongoing monitoring studies predict the remaining glaciers in Africa are predicted to disappear by the middle of the 21st Century. These will likely be the only glaciers present on the continent for some tens of thousands of years, until the next global ice age. This paper considers the implications of the shrinking cryosphere in Africa for the surrounding environment and local communities. Glacier retreat will give rise to significant and irreversible downstream effects on East African mountain landscapes in future decades, including impacts on water resources; slope stability and geohazards; ecosystems and ecosystem services; and human socioeconomic and cultural activities and heritage. This foresight study is the first to discuss future environmental impacts of deglacierization in East Africa, and this is framed around understanding the interconnections that exist between physical and human landscape elements in mountainous regions. A key outcome is the identification of elements of mountain systems that are most sensitive to environmental disturbance as a result of global warming, such as long-term water availability and processes that give rise to geohazards, and highlighting the need for management and mitigation of these varied impacts. • Glaciers in East African mountains are rapidly melting. • These will be the only glaciers present in Africa until the next global ice age. • Glacier retreat will result in significant and irreversible downstream environmental effects. • Most affected will be regional water resources, geohazards, and ecosystem services. • Change in mountain landscapes will impact on socioeconomic and cultural activities. [ABSTRACT FROM AUTHOR]

Patagonia features the most extensive glaciers of the Southern Hemisphere, excluding Antarctica, and a vast inventory of glacial landforms, so it is thought to have played a key role in (paleo)glacier studies since the late 19th century. However, no systematic attempts to characterize the specific research trends and the scientific community focused on Patagonian cryosphere have been conducted so far. To fill this gap, we analyzed the metadata associated to 305 articles compiled from the Web of Science database following a bibliometric approach covering the period between 1976 and 2020. Our results point to an irregular but net increase on the number of contributions on Patagonian (paleo)glaciers. Mass balance analyses based on satellite data of present-day glaciers and the reconstruction of past glacier activity by dating glacial landforms formed during the Last Glacial Termination, were the most addressed topics during the analyzed period. Patagonian (paleo)glacier studies are mostly published in generic Earth Sciences publications, followed by Quaternary and glaciological journals. Most of the studies were led by scientists from the United Kingdom, followed by Chile, Argentina and United States. In terms of collaborations, these studies can be divided into two main clusters, one composed by researchers from United States, Chile and Argentina institutions, and another mostly composed by British researchers. So far, the most prolific authors are nearly equally distributed in nationality, yet gender inclusion and international collaborations are still caveats that must be solved. Even though our query on the Web of Science missed highly influential (so-called) grey literature, such as local scientific journals and technical reports, the reviewed scientific literature unambiguously indicates that Patagonia is a privileged location for (paleo)glaciers studies worldwide and that it will continue offering vast opportunities to tackle critical questions related to global cryosphere and past-to-present climate changes. • Patagonia is a privilege site for studying present and past glacier dynamics and the evolution of climate changes at hemispheric and global scale. • Glacier dynamics during the 20th century and and the Last Glacial Termination are the most common topics addressed in past decades in the WOS. • Patagonian (paleo)glacier studies has contributed to the development or improvement of diverse analytical techniques. • United Kingdom, United States, Chile and Argentina produced the largest number of WOS-listed papers on (paleo)glaciers in past decades. • The related scientific community is fairly heterogeneous. Although, inclusion and international collaboration issues still need to improve. [ABSTRACT FROM AUTHOR]

Reconstructing three-dimensional palaeoglacier surface, thickness, and volume provides useful information for quantifying palaeo-climate conditions during glacial stages and assessing the impact of glacier change on water resources. A glacial flowline model has been implemented in Excel and ArcGIS to reconstruct palaeoglaciers based on digital elevation models and geomorphic constraints, such as moraines and trimlines that represent the margins and local heights of palaeoglaciers, respectively. However, significant efforts are still needed in using these tools for palaeoglacier reconstruction, such as digitizing flowlines, adjusting shear stress, and deriving shape factors. This paper presents an automated method, PalaeoIce, to reconstruct palaeoglaciers using geomorphic constraints. Coded in python, PalaeoIce is an ArcGIS toolbox with a set of tools to generate glacial flowlines, optimize shear stress, derive shape factors, calculate ice thickness values along flowlines, and interpolate palaeo ice surfaces based on geomorphic constraints. The use of PalaeoIce is demonstrated using extant glaciers with measured thickness values and moraines/trimlines of the Little Ice Age (LIA) and Marine Isotope Stage (MIS) 2 in the eastern Tian Shan, China. The reconstructed ice thickness values of Glacier No. 1 in this area show a reasonable agreement with field measurements with 1.4 % and 5.4 % differences between measured and reconstructed mean ice thickness values using the two methods included in PalaeoIce: a revised ice thickness model for extant glaciers and a palaeoglacier reconstruction method based on glacier outlines, respectively. Two approaches are then illustrated for palaeoglacier reconstructions using two sets of geomorphic constraints: one with the fully reconstructed glacier outlines during the LIA, and the other with just the terminal moraine and limited trimlines during MIS 2. PalaeoIce can significantly improve the efficiency of palaeoglacier reconstructions and the understanding of the impact of glacier change on water resources. • An automated method, PalaeoIce, is presented for palaeoglacier reconstruction. • Tools are developed to create flowlines, modify DEM, and reconstruct palaeoglaciers. • Reconstructed ice thickness data are validated by field measurements in Tian Shan. • Target geomorphic features are of importance for palaeoglacier reconstruction. [ABSTRACT FROM AUTHOR]

• Internal humidity and drying shrinkage tests were performed on RATIC with various RCA contents. • A model was proposed to predict the drying shrinkage of RATIC resulting from the internal humidity. • The drying shrinkage mechanism of RATIC was revealed. The unique internal structure and basic properties of recycled coarse aggregate (RCA) and glazed hollow bead (GHB) complicate the shrinkage deformation of aggregate thermal insulation concrete (RATIC). To reveal the time-dependent law and mechanism of the drying shrinkage of RATIC, we experiment on the internal humidity evolution and drying shrinkage of RATIC with various contents of RCA. Moreover, we establish a model for predicting the time-dependent drying shrinkage of RATIC considering the replacement ratio of RCA and the development of the internal humidity of concrete using regression analysis. The results show that adding recycled coarse aggregate promotes cement hydration and water diffusion but aggravates the reduction of internal humidity and the development of the drying shrinkage of the RATIC. This paper proposes a model describing the drying shrinkage of RATIC at various contents of RCA and relates it to the changes in internal humidity so as to provide possible explanations for the drying shrinkage of RATIC influenced by the internal humidity. Finally, the drying shrinkage mechanism of RATIC is well explained using the capillary theory and the internal curing effect. [ABSTRACT FROM AUTHOR]

Glacier retreat in high altitude areas triggered by anthropogenic warming exerts a profound impact on the ecology of glacier-fed lakes. In this paper, we report on the results of a multi-proxy analysis of a Lateglacial (13.3–11.3 cal kyr B.P.) core obtained from the glacier-fed Kanas Lake in the Altai Mountains, China, to understand the responses of aquatic ecosystems to meltwater influxes. Core intervals with high sand fractions and enriched silicon dioxide and zirconium (~11.5, 11.7, 11.8, 12.2 and 13.0 cal kyrs B.P.) reflect intense meltwater pulses from alpine glaciers. In the core, these pulses generally coincide with low abundance of littoral cladocerans, high abundance of planktonic Pediastrum , and high phosphorus concentrations. Our results suggest that intense meltwater influxes not only brought nutrients (nitrogen and phosphorus) into the lake and promoted phytoplankton growth, they also generated cold, turbid water masses and restricted the growth of benthic algae and invertebrates. Therefore, we infer that future anthropogenic warming may lead to significant changes in the structure and function of aquatic ecosystems in glacier-fed lakes worldwide. • We study the impact of Lateglacial meltwater influx on the aquatic ecology of Kanas Lake, China. • Intense meltwater influx delivered nutrients to the lake and promoted the phytoplankton growth. • Intense meltwater influx also generated turbid and cold waters and restricted the benthic organism growth. • Future anthropogenic warming may lead to significant changes in aquatic ecosystems of glacier-fed lakes worldwide. [ABSTRACT FROM AUTHOR]

Glaciers, as the core part of the cryosphere, are very sensitive to climate change. As an indicator of glacier changes, the characteristics of glacier-originated rivers have profound significance to global climate change and local water resources. In this paper, the Mingyong River, a glacier-originated river replenished by groundwater, was selected to study the river hydrological cycle characteristics by integrating natural tracer radium isotopes with hydrochemical parameters. The results showed that there were significant differences in radium isotope activities and hydrochemical parameters between groundwater and river water, and the radium activities increased along the river, which reflected the fact that the river was supplied by groundwater seepage. We also found that the activity ratios of 224Ra/228Ra in river and groundwater were less than one unit, which indicated that the groundwater and river water circulated rapidly and that the radioactive equilibrium of short-time radium isotopes had not yet been reached. According to the geochemical behavior of radium in river water body, the mass balance equation of radium was established. 228Ra and 224Ra were used to estimate the groundwater seepage of different segments of the Mingyong River. The results demonstrated that the groundwater seepage fluxes calculated by 224Ra and 228Ra were similar and increased along the river from 123.12 to 657.68 m3 m−1 d−1. Our results have certain significance in revealing the characteristics of the local hydrological cycle and demonstrate that radium isotopes can be used as a tool to estimate the groundwater discharge of rivers in glacial environments. [Display omitted] • Estimated the groundwater seepage along a glacier originated river. • Ra isotopes mass balance model of the river is established. • Verified Ra isotopes is an effective tool in glacial area. [ABSTRACT FROM AUTHOR]

The first three papers in the Loess and Bee-eaters series sought to establish links between the nesting of bee-eater birds (family Meropidae) and the occurrence of loess deposits. For the European bee-eater there is a close and fairly obvious relationship; for the Carmine bee-eater nesting in the 15 N band of Africa more assumptions and adjustments have to be made, and for the Blue-cheeked bee-eater nesting in the Indus region the relationship is becoming vague and more speculative. The trend continues with the Australian bee-eater- the rainbowbird ( Merops ornatus ). We lack precise maps of loess distribution in Australia and there is an equal lack of detailed and accurate maps of the distribution of rainbowbird nesting. Loess in Australia is elusive; the maps of Kriger and Scheidig show little detail and are essentially contradictory. If the deterministic theory of loess deposit formation were applied, it would suggest that loess should be found in the region where Pleistocene cold-phase mountain glaciers occurred. In the last glacial phase there was very little glacial occurrence in Australia; probably a limited region near Mount Kosciuszko. This places some glacial activity in the extreme southeast of the country. This agrees, more or less, with the data on the Kriger map. Fry has mapped the breeding zones of the rainbowbird and they are concentrated in the southeast and southwest. The maps are not precise but there does seem to be indications of co-existence of bee-eater nests and loessic regions. This is not the clearcut relationship which has been observed with the European bee-eater but it is suggestive. The ill-defined loess/dust regions and the poorly demarcated nesting zones of the rainbowbird do seem to be coincident. Better mapping is urgently required for loess in Australia, and nesting zones of M. ornatus . It may be that dust rather than loess is the ground material to be observed in Australia. There are still problems of integrating the dust and loess concepts, but mapping of dust deposits does produce some coincidence with rainbowbird nesting. The region of Vertisol occurrence appears to be a barrier to the spread of rainbowbird nesting. [ABSTRACT FROM AUTHOR]

Flanking structures are deflections of an existing planar fabric (e.g., foliation) alongside a cross-cutting element (e.g., a vein) that can develop in a wide range of rock types and glacier ice. Nearly all published examples of flanking structures are interpreted to have formed either under simple shear or transpressional general shear, although theoretically they should also form under transtensional general shear. This paper describes the geometry and development of transtensional flanking structures in glacial ice of the Pasterze, Austria's largest alpine valley glacier. The cross-cutting elements are a few metres long and are interpreted as fractures that rotate into the shear flow and consequently accommodate anti- and synthetic offset, forming a- and s-type flanking folds. However, shear bands, with co-shearing cross-cutting elements inclined against the shear flow, are absent. The geometries of the mapped structures are successfully reproduced with a semi-analytical modified Eshelby solution for a frictionless cross-cutting element embedded in a linear viscous medium deforming under a remote transtensional sub-simple shear. The geometry of the mapped flanking folds, the absence of shear bands, the spatial variation of cross-cutting element orientations and the geometry of the glacier's splaying crevasses are consistent with two-dimensional transtensional sub-simple shear caused by down-glacier valley widening. [Display omitted] • Transtensional flanking structures are exposed in Austria's largest valley glacier. • Splaying crevasse geometries are consistent with a decelerating glacier flow. • The transtensional geometries are reproduced with semi-analytical models. • Diagnostic features of transtensional flanking structures are elaborated. • Shear zones in natural rocks rarely exhibit transtensional flanking structures. [ABSTRACT FROM AUTHOR]

Accurate knowledge of glacier motion variations can provide critical information for assessing glacier mass balance changes. For fast-flowing high mountain glaciers, SAR Intensity-tracking may be the most appropriate technique to measure their motions. However, due to the slant range imaging mode, topographic relief can give rise to pixel disalignments in SAR image and then bring errors to SAR Intensity-tracking. As a result, the application of SAR Intensity-tracking has been limited to SAR pairs with short baselines, because the use of image pairs with long baselines would suffer significant topographic effects over mountainous regions. This paper presents an improvement to SAR Intensity-tracking by adding an explicit procedure of topographic correction. Such correction will not only significantly increase the accuracy of the SAR pairs with shorter baselines, but also allow the image pairs with longer baselines to be taken advantage of, instead of letting them to be dismissed otherwise. Using the improved SAR Intensity-tracking technique, we derive the highly precise motion variation patterns of 11 giant glaciers in Tuomuer–Khan Tengri Mountain Ranges, one of the largest glacial centers in Tien Shan. The results manifest that most glaciers there saw flow deceleration during the observation interval (6 January 2007–4 March 2011), except the Northern and Southern Inylchek Glacier. Regarding the glacier motion mechanism, ice thermal character and climate features there, we deduce that the flow acceleration and deceleration should be the sign of glacier mass gain and loss, respectively, and the sharp and slight flow decelerations should correspond to remarkable and mild mass loss, respectively. We confirm these deductions by exploring the close link between the long-term motion variations and the dynamic patterns of these glaciers. The obvious diversities of the dynamic patterns among the studied glaciers are ascribed to the discrepancies of the glaciers' location and scale. Longer observations are still needed to confirm or redefine these findings in the future though. Provided that the precipitation keeps increasing, whether the glaciers in Tuomuer–Khan Tengri Mountain Ranges will regain mass or not has not been determined yet. [ABSTRACT FROM AUTHOR]

• Glaciomarine environmental stress produce a decreasing in the OM availability. • Sedimentation of terrestrial OM contributed with a significant fraction of total OM. • Soft-bottom benthic communities exhibited a species richness longitudinal gradient. • The C/N ratio in benthic fauna suggest preferential organic carbon use. The benthic community in the Chilean Patagonia is as rich and highly diverse as the spatial variation of its habitats and food sources. Environmental stress from glacier melt and river discharge are known drivers of benthic community dynamics. Here, we analyze longitudinal patterns of soft-bottom benthic communities across transects of glacier-marine environments and how these habitats may respond to changes in the environmental conditions. To assess the relationships between environmental heterogeneity (marine and glacial habitats) and benthic biodiversity, this paper reviews biological (mega- and macroinfauna) and sedimentological dataset from multiple oceanographic campaigns in Chilean Patagonian fjords. Furthermore, we analyze isotopic compositions of epibenthic and macroinfaunal organisms (δ13C/δ15N and C/N) to determine particulate organic carbon (POC) and particulate organic nitrogen (PON) availability and organismal stoichiometric budgets within each benthic community. Our results showed that glaciomarine and glaciofluvial environmental stress negatively affected nutrient reservoirs and organic matter (OM) availability, and hence produced changes in benthic diversity and trophic structure throughout the fjords. These conditions shaped the benthic community where small-bodied polychaetes and opportunistic species dominated. Additionally, we found a strong relationship between OM and nutrient availability with faunal isotopic composition, but a decoupling in C/N ratios between fauna and sediment OM, suggesting preferential organic carbon use under limited nitrogen in fjord sediments. [ABSTRACT FROM AUTHOR]

Glacier retreat has caused the emergence of numerous moraine-dammed glacial lakes (MGL) over the last century which have become research foci in many mountain regions of the world. Outbursts of MGLs have caused destructive floods and debris flows, leading to numerous human casualties and significant material damage. The mountains of South-Eastern Kazakhstan have also become prone to lake outburst floods and related debris flows, specifically in the second half of the 20th century. This paper presents and reviews existing surveys and knowledge along with results of own investigations on the formation of MGLs and the characteristics of lake outburst floods and debris flows in the Kazakh part of Tien Shan. We suggest a workflow to identify the most dangerous types of lakes and provide information about their morphogenetic features and hazard criteria. The number of MGLs increased since the 1970s with more than 160 existing in 2018. Forty were identified as being dangerous. Forty-eight lake outbursts occurred since 1950 with all the documented events happened between end of June and end of August. The most dangerous outbursts were caused by ruptures in ice-cored moraine dams. Outbursts of nine MGLs caused disastrous debris flows, with some occurring repeatedly. The number of outbursts decreased since the year 2000 compared to 1970–2000. However, due to ongoing glacier retreat new lakes are forming at higher altitudes. Their greater potential energy makes possible future outbursts more dangerous. Re -evaluation of existing methods to calculate the water volume and peak discharge based on bathymetric measurements and observed outbursts revealed that the applied equations provide suitable approximations and allow supporting mitigation and prevention measures. Finally, the presentation of implemented measures to lower the water level using siphons or artificial flow channels shows that they can reduce the lake outburst hazards. However, they are associated with risks and financial costs and it needs to be carefully considered whether protection measures of the endangered areas are more cost effective. [ABSTRACT FROM AUTHOR]

In this paper we used ground-based thermal infrared imaging to investigate the spatial variability of surface temperatures on a mountain glacier at high spatial resolution and to estimate the supraglacial debris thickness distribution. The surveyed area is the eastern tongue of Gran Zebrù glacier, a small mountain glacier of the Ortles-Cevedale group (Italy). A FLIR E85 Thermal Camera was used to obtain a panoramic thermal image of the glacier surface on 30 September 2019 that was calibrated and georeferenced in order to obtain surface temperatures. Based on field data, debris thickness and debris surface temperature were correlated by using an exponential equation. The equation was used to estimate debris thickness on the glacier from the temperature data. The results show a spatial variability of surface temperatures, with the lowest temperatures found on snow and ice surfaces, and the highest on supraglacial debris. The estimated debris thicknesses show an inhomogeneous distribution, with a calculated mean debris thickness of 0.09 m in the areas of continous debris coverage. We found a good correspondence between measured and estimated debris thickness at 30 validation points (RMSE = 0.04 m and r = of 0.92). We demonstrated that ground-based thermal imaging can provide very high resolution maps of glacier surface temperatures and of debris thickness that can be used for the estimation of glacier ablation, with a spatial resolution more suitable than that offered by satellite data, especially for glaciers with a small area and with a heterogeneous surface. • Thermography is a valid tool to map debris thickness. • There is a good relation between debris thickness and surface temperature until 0.5 m of thickness. • Debris thickness spatial variability is relevant for the ablation of a glacier. • There is a good relation between estimated and measured debris thickness with the thermography. [ABSTRACT FROM AUTHOR]

The relationships between pedogenetic processes and fluvial-coastal dynamics in the Po Plain have been reconstructed through sedimentological analysis and correlation of ca. 170 core data chronologically constrained by 376 radiocarbon dates. Vertically stacked, weakly developed paleosols within Upper Pleistocene and Holocene mud-prone strata testify to intermittent pedogenesis, periodically interrupted by overbank sedimentation. Individual paleosols are laterally traceable for tens of km and exhibit A-Bk-Bw, A-Bk or A-Bw profiles. Stratigraphically ordered 14C calibrated ages from A organo-mineral horizons testify to slow aggradation during 4–6 thousand years-long exposure periods. Burial ages, with an error of few centuries, are provided by plant debris at the top of A horizons. Millennial-scale climate oscillations and glacio-eustasy are the main drivers of the pedo-sedimentary evolution of the area during the last 50 kyr. Upper Pleistocene paleosols (P1-P3) developed in well-drained floodplain environments, during relatively warm periods. Paleosol burial occurred during colder phases. High-sediment-supply during the Last Glacial Maximum hindered pedogenesis and led to the accumulation of 3–10 m-thick overbank strata. Widespread soil development (paleosol PH) occurred at the end of Last Glacial Maximum, following the retreat of Alpine glaciers and the afforestation of Apennine drainage basins. At distal locations, paleosol PH was progressively buried under estuarine sediments during the Holocene phases of post-glacial sea-level rise. Beyond the area of marine influence, burial ages of paleosol PH change from a place to another without specific spatial trends and reflect upstream fluvial sedimentation dominated by avulsions and deposition of spatially restricted alluvial units. Holocene (H1−H2) paleosols show a poor correlation potential and laterally variable degree of maturity that reflect avulsive sedimentation patterns and crevassing. This paper provides insights on the timing and mechanisms of formation and burial of weakly-developed paleosols. The outcomes of this research are applicable to similar Quaternary alluvial systems, and may help interpreting ancient paleosol-bearing successions. • Po Plain pedostratigraphy reveals relations between pedogenetic and alluvial events. • Upper Pleistocene-Holocene stacked paleosols testify to intermittent pedogenesis. • Radiocarbon dates permitted to estimate the duration of the main pedogenetic phases. • Climate change and eustasy controlled Late Pleistocene pedo-sedimentary evolution. • Discontinuous Holocene paleosols reflect avulsive sedimentation and crevassing. [ABSTRACT FROM AUTHOR]

• Landform-sediment record of glaciation in three Northern Romanian Carpathian ranges. • Geometry and ELA of 12 cirque glaciers were reconstructed. • Mean climatic LGM ELA between 1740 and 1870 m. • Climatic ELA largely controlled by local topoclimatic factors. In the Northern Romanian Carpathians (NRC) small Pleistocene cirque glaciers have formed in several isolated mountain massifs exceeding 1800 m asl. This paper brings forward new geomorphological evidence of marginal glaciation in the Călimani, Suhard, and Gurghiu Mountains which are the southernmost glaciated areas of the NRC. We reconstructed the extent and ice-surface geometry for 12 palaeo-glaciers in the study area during the Maximal Ice Extent (MIE) which is attributed to LGM. The equilibrium line altitudes (ELAs) calculated using the area-altitude-balance-ratio (AABR) 1.6. were between 1740 m and 1870 m which is the highest value in the Eastern Carpathians and one of the highest in the entire Carpathians. The specific features of the Călimani and Gurghiu Mountains are the extensive, gentle outer slopes of volcanic calderas that play an important role as additional areas for snowblow accumulation. Inclusion of the potential snow contribution area (snowblow and avalanche accumulation) in the ELA calculation resulted in an additional upward ELA shift up to 66 m (up to 40% of the glacier elevation range). Our data indicate that small cirque glaciation in the NRC could develop when mountain ranges are at least 100 m above the extrapolated regional ELA. The general ELA pattern in the NRC shows a positive trend (∼3 m/km) which could reflect both the general rise in temperature and the starvation of precipitation toward the southeast. However, the observed eastward ELA rise on W-E transects in the Eastern Carpathians shows a pure precipitation effect and indicates the influence of zonal atmospheric circulation in the far interior of Europe during the LGM. [ABSTRACT FROM AUTHOR]

Abstract: The cost and effort of installing and maintaining an automatic weather station (AWS) on a glacier may be mitigated by the possibility of gathering sensor data in near real-time, and of controlling and programming the station remotely. In this paper we report our experience with upgrading an existing AWS, operating over an Italian glacier, from a mere datalogger into a networked sensing station. Design choices, energy constraints and power-aware programming of the station determined by harsh environment are discussed. Deployment operations and results are described. The upgraded AWS provides low-power connectivity from a remote location and is able to serve as a base station for a wireless sensor network working in the glacier. [Copyright &y& Elsevier]

As typical inland river basins in China, the Ürümqi River Basin and the Aksu River Basin were selected as study areas in this paper. In the past several decades, the climate has had a tendency to change from warm-drying to warm-wetting, with a coinstantaneous response by mountain glacier meltwater of these areas. Comparing questionnaire survey data with scientific observation, this study focused on the character of public perception on climate and cryosphere changes, the changes' possible impacts on water resources, and adaptation measure choices by the public. Results presented in this study showed that: 1) Perceptions of most respondents on climate and cryosphere changes conform to objective facts, but some of them still have suspicion relating to these environmental changes; 2) Even though increasing precipitation and glacier meltwater has caused an increased water supply, due to the increasing demand of the unit area water for agriculture (industrial and living water demand may be involved), water shortage is still a big problem in sustainable development. Because of unemployment or the inconspicuous benefits of water-saving measures, the wasting of water resources may be a serious problem in these areas; 3) Most people preferred to choose the adaptation measures implemented by government and policy-making departments. Some people showed more preference for measures avoiding unfavorable natural environmental consequences. Public perceptions on the urgency of individual participation are still inadequate. Some of the measures should be communicated broadly and warmly encouraged; 4) Public choices of adaptation measures for climate and cryosphere change are impacted by demographic factors such as age, gender, region, nationality, education and occupation. The impacts of such factors are complicated. [ABSTRACT FROM AUTHOR]

Abstract: Alamkouh is one of the most typical glaciers in Iran which was assorted as an alpine glacier and it''s clumsily covered by heavy debris (refereed as supraglacial debris). The source of this debris and debris covers that exist outside the glacier boundaries (refereed as periglacial debris) are similar and due to the same properties of these two types of covers, the automated mapping of the actual glacier area is impossible. By considering this fact that the most significant parameter differentiating these covers is the surface temperature, the aim of this paper is to distinguish the supraglacial and periglacial debris and outline the debris covered glacier boundary by means of optical (Worldview-2 satellite imagery) and thermal (Landsat-TM sensor) remote sensing data. After collecting GCPs from different member of glacier in field operation, Neural Network classification has been used to delineate the actual area of glacier. The accuracy of such thermal–optical based method was analyzed by comparison of its result to the geomorphometric- based techniques and manual delineation. These analysis shows that the result of thermal–optical approach has a significant differences with geomorphological approach especial in the ablation area which this can be related to the recession of glacier in recent years. But, unlike the geomorphometric method, by comparison the result of our new method with manual digitization of glacier (by means of very high spatial resolution imagery) it was found that there are too many similarities between these two different methods and the combination of thermal and optical properties of such glaciers could be useful to delineate there actual area more precisely. [Copyright &y& Elsevier]

Accelerated glacier and ice sheet retreat and thinning in recent decades has profound consequences for catchment sediment supply with attendant repercussions for nutrient cycling, carbon fluxes and natural resource management. This paper evaluates the impacts of deglaciation on sediment yields from glaciated, deglaciating and recently-deglaciated catchments. It summarises the key characteristics of sediment yields from glaciated catchments to be that they span five orders of magnitude, vary with latitude and are greatest in high-relief and tectonically-active regions. We review the available quantitative data on sediment yields from glaciated catchments and we comment extensively on spatio-temporal variability to understand global to local and inter- and intra-catchment controls. Significant gaps in the available sediment yield data and also in our knowledge of sediment sources, pathways and sinks are identified. We constrain a set of novel approaches by which these gaps could be addressed. In particular, we suggest that the opportunities presented by emerging datasets and analytical methods enabling landcover changes, Digital Elevation Model (DEM) change detection, analyses of connectivity and analyses of sediment plumes are exciting and these approaches should become practical tools for understanding intra- and inter-catchment sediment yields from deglaciating landscapes. We showcase preliminary studies utilising these datasets and they are used to formulate hypotheses designed to stimulate further research. • Explanation of importance of understanding sediment yields from deglaciating catchments. • Concise summary of the key characteristics of sediment yields from glaciated catchments. • Review of spatio-temporal trends in global data compilation. • Identification of gaps in the available data and therefore our knowledge. • Suggestions for capitalising on emerging datasets and methods to address these gaps. [ABSTRACT FROM AUTHOR]

Glacier recession in response to climate warming has resulted in an increase in the size and number of glacial lakes. Glacial lakes are an important focus for research as they impact water resources, glacier mass balance, and some produce catastrophic glacial lake outburst floods (GLOFs). Glaciers in Peru have retreated and thinned in recent decades, prompting the need for monitoring of ice- and water-bodies across the cordilleras. These monitoring efforts have been greatly facilitated by the availability of satellite imagery. However, knowledge gaps remain, particularly in relation to the formation, temporal evolution, and catastrophic drainage of glacial lakes. In this paper we address this gap by producing the most current and detailed glacial lake inventory in Peru and provide a set of reproducible methods that can be applied consistently for different time periods, and for other mountainous regions. The new lake inventory presented includes a total of 4557 glacial lakes covering a total area of 328.85 km2. In addition to detailing lake distribution and extent, the inventory includes other metrics, such as dam type and volume, which are important for GLOF hazard assessments. Analysis of these metrics showed that the majority of glacial lakes are detached from current glaciers (97%) and are classified as either embedded (i.e. bedrock dammed; ~64% of all lakes) or (moraine) dammed (~28% of all lakes) lakes. We also found that lake size varies with dam type; with dammed lakes tending to have larger areas than embedded lakes. The inventory presented provides an unparalleled view of the current state of glacial lakes in Peru and represents an important first step towards (1) improved understanding of glacial lakes and their topographic and morphological characteristics and (2) assessing risk associated with GLOFs. • We present a new contemporary and comprehensive lake inventory for the Peruvian Cordilleras • We provide a set of inventorying methods to facilitate replicability in other locations, globally • We record and analyse a number of important lake metrics for understanding GLOF hazards • We estimate lake volume in all glaciated cordilleras and compare these with other studies [ABSTRACT FROM AUTHOR]

The Late Upper Palaeolithic of Europe, particularly the Last Glacial Maximum (LGM: 26-19 kyr cal BP), was a time of dramatic climatic changes. Fauna, and the humans that preyed on them, were forced to adapt their behaviours in response to climate changes to survive. The Cantabrian Region of northern Spain was continuously inhabited during this period when many other areas of Europe were inhospitable. The site of Las Caldas (Asturias) was repeatedly occupied by hunter-gatherers during the Solutrean (26.1–20.3 kyr cal BP) and Magdalenian (18.5–14.3 kyr cal BP). This paper uses δ13C and δ15N stable isotope analysis of red deer (Cervus elaphus) and Spanish ibex (Capra pyrenaica) remains to reconstruct past environments, ungulate niches and habitats, and to understand how this impacted on their availability as a prey source. Results show that during the Solutrean, cold and potentially wet LGM conditions were experienced and ibex lived in lower altitudes, likely due to reduced vegetation, and even small glaciers on the higher mountain slopes. Improved environmental conditions in the Magdalenian allowed ibex to live in their preferred habitat of higher altitudes. Ameliorated Late Glacial conditions correspond with changing economic hunting strategies at the site. Humans exploited wider ecological zones, over larger distances, which coincides with population growth, and greater connectivity across the Cantabrian region. This research highlights the importance of characterising the complex interactions between humans, animals and environments during the Late Pleistocene and how they responded to rapidly changing environmental conditions. • Bone collagen δ13C and δ15N values used to reconstruct environments and faunal niches between 26 and 14 kyr cal BP in N. Spain. • Harsh Solutrean conditions affected ibex habitats, and they moved to lower altitudes. • Improved Magdalenian conditions coincided with exploitation of wider ecological zones. • Increased Magdalenian human populations pressured resources, affecting subsistence strategies. [ABSTRACT FROM AUTHOR]

• Lakes in the endorheic basin exhibited a rapid expansion since 2000. • The significant lake expansion was observed in the Hoh Xil region. • Lake expansion was closely related to precipitation and permafrost degradation. • Meltwater from permafrost thawing contributes to 21% of lake volume change. • Glacier retreat contributed to expansion of several large lakes. The QTP (Qinghai-Tibet Plateau) holds the greatest concentration of high-elevation inland lakes in the world, and most of these lakes are located in the QTP endorheic basin. Accelerated lake expansion in the endorheic basin since 2000 has been confirmed by many studies, but there is disagreement as to which components of the water balance explain most of the lake expansion. In this paper, based on Landsat images, meteorological data, glacier data and permafrost monitoring data, we analyzed the spatial–temporal changes in lake area and further explored the driving factors behind rapid lake expansion in different zones in the endorheic basin. The results suggested that the spatial pattern of trends in lake area in the endorheic basin from 2000 to 2017 showed a southwest-northeast transition from contracting to slightly expanding to rapidly expanding. More importantly, the dramatic lake expansion observed in most regions was statistically significant (0.01 ~ 26.29 km2/yr). Although retreating glaciers may have contributed to lake growth, this can not fully explain the recent lake expansion. We find that increasing precipitation was the primary driver behind lake expansion, and that permafrost degradation accelerated lake expansion. Lakes on the northern slope of the Gangdise Mountains, fed by the most rapidly retreating glaciers, were relatively stable or even contracted. In contrast, most of the non-glacier-fed lakes in the Hoh Xil region and the central endorheic basin nevertheless experienced significant expansion and slight expansion, respectively, which were mainly attributed to the greatest increase in AP (annual precipitation). Remarkable lake expansion was found in the continuous permafrost zone. The increasing ALT (active layer thickness) and soil temperature of permafrost resulted in an increase in meltwater from ground ice, the partial release of soil moisture and an amount of unfrozen water content, which has contributed to supply lakes and accelerated lake expansion. [ABSTRACT FROM AUTHOR]

The CryoSat-2 radar altimetry mission, launched in 2010, provides key measurements of Earth's cryosphere. CryoSat-2's primary instrument, the Synthetic Aperture Interferometric Radar Altimeter (SIRAL), allows accurate height measurements of sloped ice-surfaces including the highly crevassed Bering-Bagley Glacier System (BBGS) in southeast Alaska. The recent surge of the BBGS in 2011–2013, which resulted in large-scale elevation changes and wide-spread crevassing, presents an interesting challenge to the processing of the SIRAL measurements. Derivation of surface height is achieved by retracking the received waveform of the altimeter signal. Several such retracking methods have been developed. In this paper, we investigate the influence of six unique SIRAL retracking methods on (1) Digital Elevation Model (DEM) generation, (2) analysis of ice-surface topography, and (3) numerical modeling results of the BBGS during surge. First, we derive a surface DEM for each retracked dataset using kriging. The swath-processed dataset provides 100–250 times more points than the other datasets, which decreases DEM uncertainty associated with data coverage by a factor of 2–4. Differences between the six resulting DEMs imply that retracking methods can have significant effects on elevation and elevation-change analysis, but we find that lower-level processing has larger effects. Next, the sensitivity of the data-model connection is evaluated using a finite element model of the BBGS surge. We set up six modeling experiments, each initiated with a unique input surface DEM derived from the various retracking methods. While retracking choices effect estimation of unknown model parameters related to crevasse simulation, we have developed a procedure to limit these effects resulting in remarkably consistent parameter optimization across modeling experiments. Each model experiment yields an optimal friction coefficient in the sliding law of 10 − 5 M P a ⋅ a m , while estimates of the optimal von Mises stress threshold for crevasse initiation ranged between 230 and 240 k P a. • Active crevassing during a surge complicates retracking and elevation analysis. • The model parameter important for surging, the basal sliding parameter, was examined. • The model parameter important for crevassing, the von Mises threshold, was examined. • Swath processed data increases spatial coverage by a factor of 2-4, but is more noisy. • Retracking effects on modeled results are mostly reduced after 50 days of relaxation. [ABSTRACT FROM AUTHOR]

Aeolian dust has a great influence on mountain hydrology, climate, and biogeochemical cycles. Dust deposited on glaciers and snowpack of the high alpine mountains in Tibetan Plateau (TP) and its surrounding regions can provide a unique method of determining the high-elevation transport and deposition of Asian dust in the middle and upper troposphere. Long-range-transported (LRT) Asian dust is often transmitted through the high troposphere, thus studies on dust deposition in the high-elevation cryosphere can reflect the LRT information of aeolian dust, and provide an unparalleled record to understand the regional climate and environment change in the "Third Pole" region. This paper comprehensively reviews the current status of the major factors that determine aeolian dust transport, settling, and cycling, and the key components of this dust cycles in high-elevation cryosphere regions, revealed by glacial snowpack and ice-core dust geochemistry recorded in the mountain glacier areas of TP and western China. Research on glacial dust concentrations indicated that much higher amounts of aeolian dust were found to transport and cycle in the high-elevation troposphere over TP and surroundings, compared to other locations of the globe. Dust concentrations and fluxes in high elevation regions of the TP were closely related to the transport distance of the nearby dust sources (e.g. large deserts and Gobi in western China, and arid deserts on the plateau surface). Isotopes tracers (e.g. 87Sr/86Sr, and ε Hf , ε Nd) and dust size distributions revealed that aeolian dust transported over TP mainly originated from the arid and semi-arid deserts and surface crust soils on TP; Aeolian dust from the large deserts of central Asia (e.g. the Taklimakan Desert with small ratio) have not been easily transported to the hinterland of TP under the current climatic conditions. An End-Member Mixing Analysis model was also used to calculate the relative contributions of northern hemisphere dust sources to the TP glacier dust sinks. The marked spatial differences in LRT dust sources of TP glaciers were caused by the large-scale atmospheric circulation strength and interactions in the Asian region. In addition, Asian dust has a large influence on the radiative forcing of glacier and snow melt in which the iron oxide composition constitute an important driving factor. Biogeochemical cycles in cryospheric regions were significantly affected by aeolian dust cycles, influencing glacial ecosystems, meltwater geochemistry (e.g. d Fe release) and nutrients supply for downstream aquatic ecosystems. Ice core records for the past hundred years revealed a general decreasing trend of dust storm frequency and atmospheric concentration over the TP region. This work provides new insights and perspectives on aeolian dust transport and cycling in high regions of the troposphere and cryosphere of the TP, identifying critical uncertainties and priorities for future research. [ABSTRACT FROM AUTHOR]

This paper reviews the distribution, character and age of blue-ice moraines in Antarctica and asks whether there are implications for the study of former Pleistocene ice sheets in the Northern Hemisphere. Blue-ice forms where acceleration of downslope katabatic winds removes snow and causes ice to ablate. Upward ice flow compensates for the surface ablation and in some places brings rock debris to the surface to form a blue-ice moraine. Blue-ice moraines occur where topography focuses katabatic winds, notably outlet glaciers cutting through mountains and in the lee of nunataks and escarpments nearer the coast. Many Antarctic blue-ice moraines have been accumulating for millions of years. The cyclic growth and decay of Pleistocene ice sheets and the dominance of surface ablation near the ice-sheet margins are clearly different, yet there are aspects that apply to Pleistocene ice sheets. Based on Antarctic blue-ice deposits, equivalent deposits associated with former Pleistocene ice sheets are likely to: (1) lie in topographic sediment traps such as in side valleys or embayments next to outlet glaciers, (2) occur in the lee of mountains, (3) display a morphology indicating ice flow into the embayment or towards the mountain front, (4) include a wide range of lithologies derived from the inland ice sheet, yet consist wholly of local debris in places, (5) accumulate a thick deposit perhaps over successive glaciations. Further, (6) the location and intensity of moraine formation will change spatially and vertically in response to changes in the relative elevation of the surrounding mountains and its effect on ice flow. The extent to which these criteria will help in interpreting the behaviour of Pleistocene ice sheets is uncertain. But we use examples from the Greenland, Laurentide and Eurasian ice sheets to suggest that the concept of enhanced ablation by katabatic winds encouraging surface moraine formation helps resolve several puzzles. • Katabatic winds flowing over Antarctic nunataks create ablation hot spots. • Blue-ice moraines collect in such topographic sediment traps. • Similar sediment traps occurred on to Northern Hemisphere ice sheets. • The concept of topographic sediment traps helps interpretation of glacial sedimentation. [ABSTRACT FROM AUTHOR]

Glaciers formed in the highest mountains of Greece during the Late Pleistocene, but the timing of glacier maxima is poorly understood. This paper presents 27 36Cl terrestrial cosmogenic nuclide exposure ages from glacial boulders on Mount Tymphi (2497 m a.s.l., 40oN) in Epirus, northwest Greece. These ages address both a significant geographical gap in Mediterranean glacial chronologies and a temporal gap in the glacial history of this region by targeting the previously undated Late Pleistocene record. Late Pleistocene glaciers were restricted to the cirques and upper valleys of Mount Tymphi. Terminal and lateral moraines between 1700 m and 2050 m a.s.l. mark the extent of Late Pleistocene glaciers on the southern side of Mount Tymphi. Moraines marking the maximum extent of Late Pleistocene glaciation date to 29.0 ± 3.0 ka and 25.7 ± 2.6 ka, taking the oldest ages as most representative of moraine emplacement. Glaciers had retreated to the high cirques by 24.5 ± 2.4 ka during Heinrich Stadial 2. Rock glaciers formed under cold and drier conditions during this period of glacier retreat. This 36Cl dataset complements published U-series ages from secondary calcites in glacial sediments below 1700 m elevation, which demonstrate more extensive Middle Pleistocene glaciations in MIS 6 and MIS 12. A Late Pleistocene glacier maxima on Mount Tymphi at 25.7–29 ka is in good agreement with well-preserved outwash sediments dating to 24–28 ka in the Voidomatis River record downstream and is consistent with the Ioaninna basin pollen record indicating cool and wet conditions, most favourable for glacier growth, at 25–30 ka. • Glaciers formed in the highest mountains of Greece during the Late Pleistocene. • Late Pleistocene glaciers were restricted to the cirques and upper valleys of Mount Tymphi. • These glaciers reached their last maximum extents at 25.7–29 ka during cool and wet conditions. • Glaciers had retreated to the high cirques by 24.5 ± 2.4 ka under cold and drier conditions. • 36Cl TCN dating of glacial activity agrees with the independently-dated record of river behaviour. [ABSTRACT FROM AUTHOR]

Corrigendum to "Precipitation differences cause contrast patterns of glacier-melt water supplied discharge of two glacier basins between northern and southern Third Pole" [Sci. The authors would like to apologize that, due to their indiligence, there is an error detected, that is the affiliations of the authors of this paper, Ruzhen Yao and Jiancheng Shi have to be corrected. The corrected author list and affiliations are shown above. [Extracted from the article]

Understanding the dynamics of glaciers is essential for the knowledge of global sea-level rise, local freshwater resources in high mountain and arid regions, and the potential glacial hazards. In this paper, we present a two-dimensional thermomechanically coupled ice flow model named PoLIM (Polythermal Land Ice Model). The velocity solver of PoLIM is developed based on the Blatter–Pattyn approximation of Stokes flow. It uses an enthalpy formulation of the energy balance, an approach that is suitable for modeling the polythermal glaciers. PoLIM also includes a scheme for gravity-driven drainage of water in temperate ice, a subglacial hydrology model coupled with ice dynamics, and multiple basal sliding laws. The model has been verified by standard benchmark problems, including the ISMIP-HOM experiments, the enthalpy benchmark experiments, and the SHMIP experiments. PoLIM shows good performances and agrees well with these benchmark results, indicating its robust capability of simulating the thermomechanical behaviors of glaciers. • We provide an open-source 2D thermomechanical mountain flow model named PoLIM. • PoLIM simplifies the momentum balance using the Blatter–Pattyn approximation. • PoLIM implements an enthalpy formulation of the energy balance equation. • PoLIM includes a scheme for gravity-driven drainage of water in temperate ice. • PoLIM couples a cavity-sheet type subglacial hydrology model to ice dynamics. [ABSTRACT FROM AUTHOR]

In many of the world's high mountain systems, glacier recession in response to climate change is accompanied by a paraglacial response whereby glaciers are undergoing a transition to rock glaciers. We hypothesise that this transition has important implications for hydrological resources in high mountain systems and the surrounding lowlands given the insulating effects that debris cover can have on glacier ice. Despite this, however, little is known about how this transition occurs nor how quickly, which glaciers are liable to transition, the factors driving this process and the water supply implications that follow. This paper assesses the role of glacier and rock glacier textural properties from a deglaciating region of the Himalayas to begin to address some of these issues. We investigated six landsystems on the spectrum from glaciers-to-rock glaciers in the Khumbu Himal, Nepal, and sampled for clast shape and roundness during 2016 and 2017. Kite aerial photography was additionally used to capture aerial images of an ongoing glacier-to-rock glacier transitional landform (Chola Glacier) to elucidate the surface geomorphic features of a fully transitioned landform. This image data, processed using a structure-from-motion multi-view stereo photogrammetry approach, revealed the presence of a spatially coherent ridge-and-furrow surface morphology in the lower reaches of Chola Glacier, which is potentially indicative of an ongoing glacier-to-rock glacier transition. We show that glacier-derived and slope-derived clast roundness significantly statistically different (Kolmogorov–Smirnov two-sample test: D max = 0.62, two-tail p <.001; n = 1650) and suggest that sediment connectivity (i.e. linkage between sediment sources and downslope landforms) is one of the drivers of the transition process. Consequently, we hypothesise that the presence of well-developed lateral moraines along glacier margins serves to reduce this connectivity and thus the likelihood of glacier-to-rock glacier transition occurring. Understanding such processes has implications for predicting the geomorphological evolution of deglacierizing mountains under future climate warming and the water supply consequences that follow. • Debris-covered glacier and rock glacier clast roundness is statistically different. • Aerial photogrammetry was used to show rock glacier surface morphology. • Morphological evidence of a glacier-to-rock glacier transition is shown. • Large lateral moraines help to influence glacier-to-rock glacier transition. • A paraglacial model of rock glacier development is evident in the Khumbu Himal. [ABSTRACT FROM AUTHOR]