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Sathyendranath et al. ([11]) present an overview of ocean color data principles and applications, and describe how ocean color technology's strength lies in its global coverage and capability to sample the ocean biota at various spatial and temporal scales, matching the scales of the processes acting. Observations made from space comprise a fundamental component of the global observing system, contributing to a better understanding of the Earth system as a whole and its evolution, including climate and global environmental changes, under both natural and anthropogenic forcing factors. Ecosystem-based fisheries management, ocean biogeochemical cycles, ecosystem health and climate change studies utilize these data. [Extracted from the article]

Abstract—A method for estimating ocean ice cover parameters (thickness, Young's modulus, Poisson ratio, and density) that does not require the use of a source is proposed and tested on experimental data. To realize the approach, two single-channel seismic receivers located on the ice surface are required to record the vertical component of the oscillatory velocity of the seismic noise. The spectral-correlation analysis of the mutual correlation function of the noise registered by the receivers allows us to estimate the dispersion dependence of the group velocity of the bending-gravity wave propagating along the ice plate. The solution of the inverse problem is based on analyzing the variance of not only the group but also the phase velocity, which allows us to increase the amount of primary data. The obtained estimates of ice parameters are consistent with the results of independent observations carried out during the experiment, as well as with the estimates of other authors obtained for ice characteristics in the region of the experiment. [ABSTRACT FROM AUTHOR]

As one of the main means of non-destructive testing, ultrasonic waves can effectively detect damage inside rock, which provides an important basis for the evaluation of rock mechanical properties. This study investigates the ultrasonic characteristics of frozen sandstone during loading and the effect of different temperatures. Combined with the deformation and failure process of the frozen sandstone sample, variation in ultrasonic velocity, amplitude, frequency spectrum, quality factor, and energy during loading were analyzed. The results show that (1) the amplitude of ultrasonic first increased, then decreased, then increased again with the increase in axial stress ( σ 1 ), and decreased with the decrease in temperature. (2) The amplitude and arrival time of the first wave decreased as the temperature decreased. The amplitude of the first wave increased with the increase in σ 1 , while the arrival time is reversed. (3) The ultrasonic velocity ( v p ) increased as the temperature decreased. v p increased rapidly in the compaction stage and increased slowly in the elastic stage. Before the peak stress, when the stress level of sandstone samples was 0.88–0.93, v p reached its peak and then decreased rapidly due to the initiation and expansion of cracks. (4) The spectral peaks increased with the increase in σ 1 and decreased with the decrease in temperature. In addition, the quality factor and accumulated energy of the ultrasonic increase first and then decrease during loading. The relationship between the ultrasonic velocity and stress of frozen sandstone at different temperatures was established using logarithmic function fitting. [ABSTRACT FROM AUTHOR]

Despite being within the intertropical region of the planet, the Mexican territory still has glacier-covered mountains. In recent decades, important advances have been made in studies on glaciology and periglacial environment in Mexico both for current and past conditions. However, in spite of Cofre de Perote volcano (4200 m a.s.l.) being a strategically located mountain, it has not yet been studied in regards to the glacial and periglacial processes; in fact, those dynamics have modified the mountain massifs in the past. To complement the series of studies on glacial history in the high mountain environment of México, this study reconstructs the glacial cover and the periglacial environment of the volcano surface during the final stage of the Late Pleistocene based on climatic retrospective and through the identification of geomorphological features. The findings indicate the existence of a large glacier (ice cap) that covered the northern, western, and southern slopes of the mountain; while in the eastern sector there were two small glaciers, one being of cirque type, and the other of valley type. The current temperature conditions prevent the occurrence of permanent ice bodies; at the same time, it was found that the periglacial blockfields of the slopes is a legacy of the climatic conditions that prevailed at the end of Late Pleistocene. [ABSTRACT FROM AUTHOR]

Glacial detachment is a newly emerged glacial hazard type, and more than 20 cases have been identified worldwide. The Xiao Ma Glacier in the Amney Machen Mountains, northeastern Tibetan Plateau, experienced an intensive detachment of the terminal low-slope glacier in 2004, forming a large dammed lake downstream and burying 2.27 km2 of grassland. An advanced multi-phase r.avaflow model was used to simulate this glacier detachment event to reconstruct its slide mechanism and dynamic process. In total, 9.77 × 106 m3 mass detached were categorized into three different phases according to their properties: the old ice remaining in the middle layer following the 1988–1997 glacier surge (47% of total volume), new ice in the upper layer originating from the 2003–2004 surge, which directly caused the 2004 detachment (48%), and subglacial water trapped in the bedrock (5%). The modeling results showed that the glacier detachment–induced debris flow reached a peak discharge of 0.25 × 106 m3/s at 40 s at the mouth of the Xiao Ma Valley, and the entire propagation process was completed within 140 s. The initially trapped meltwater dominated the debris flow state, with a maximum velocity of 103 m/s. The underlying old glacial ice was pushed and deposited to the front of the fan, and the new ice in the upper layer was primarily deposited over the middle fan. Additionally, several important parameters in the r.avaflow model were recommended for the optimal interval of values via optimality analysis, and the potential of the model to be extensively applied for large-scale risk assessment was discussed under relatively simple settings. The modeling of the 2004 Amney Machen glacier detachment has resulted in a comprehensive understanding of the dynamic processes of such events, which is significant for future glacier disaster simulation and assessment thereby improving regional strategies in hazard early warning, prevention, and mitigation. [ABSTRACT FROM AUTHOR]

The geology, tectonic history and landscape evolution of ice-covered East Antarctica are the least known of any continent. Lithic boulders eroded from the continental interior and deposited in glacial moraines flanking the Transantarctic Mountains provide rare constraints on the geological history of central interior East Antarctica. Crystallization ages and ice velocities indicate these glacial erratics are not sourced locally from the Transantarctic Mountains but rather originate from the continental interior, possibly as far inland as the enigmatic Gamburtsev Subglacial Mountains. We apply low-temperature thermochronology to these boulders, including multi-kinetic inverse thermal modeling, to constrain a multi-stage episodic exhumation history. Cambro-Ordovician and Jurassic rapid-cooling episodes correlate with significant exhumation events accompanying Pan-African convergence and Gondwanan supercontinent rifting, respectively. Here we show that while Cretaceous rapid cooling overlaps temporally with Transantarctic Mountains formation, a lack of discrete younger rapid-cooling pulses precludes significant Cenozoic tectonic or glacial exhumation of central interior East Antarctica. Glacially transported igneous rocks eroded from the deep interior of ice-covered East Antarctica constrain a remarkable episodic cooling and exhumation history that helps unravel its mysterious tectonic evolution over the last 500 million years. [ABSTRACT FROM AUTHOR]

The motion of glaciers can be simulated with the p\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\varvec{p}$$\end{document}-Stokes equations. Up to now, Newton’s method to solve these equations has been analyzed in finite-dimensional settings only. We analyze the problem in infinite dimensions to gain a new viewpoint. We do that by proving global convergence of the infinite-dimensional Newton’s method with Armijo step sizes to the solution of these equations. We only have to add an arbitrarily small diffusion term for this convergence result. We prove that the additional diffusion term only causes minor differences in the solution compared to the original p\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\varvec{p}$$\end{document}-Stokes equations under the assumption of some regularity. Finally, we test our algorithms on two experiments: A reformulation of the experiment ISMIP-HOM B\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\varvec{B}$$\end{document} without sliding and a block with sliding. For the former, the approximation of exact step sizes for the Picard iteration and exact step sizes and Armijo step sizes for Newton’s method are superior in the experiment compared to the Picard iteration. For the latter experiment, Newton’s method with Armijo step sizes needs many iterations until it converges fast to the solution. Thus, Newton’s method with approximately exact step sizes is better than Armijo step sizes in this experiment. [ABSTRACT FROM AUTHOR]

Glacial environments can have significant impacts on the surrounding landscape and nearby populations when affected by volcanic activity. As such, glaciovolcanic interactions and related hazards have received substantial attention during the last few decades. In contrast, the study of void spaces created by these interactions—glaciovolcanic cave systems—remains underrepresented. This review outlines the global distribution of glaciovolcanic caves and describes examples of both historical and ongoing research advances, most of which are limited to volcanoes of the Cascade Volcanic Arc and Antarctica. Examples range from a largely static fumarolic ice cave system in the crater of Mount Rainier to glaciovolcanic cave genesis and evolution in the crater of Mount St. Helens, where the advancing glacier ice is interacting with ongoing fumarolic activity and generating new cave systems. This review includes various volcanic subfields and also brings together additional disciplines including speleology, microbiology, and astrobiology. Due to the importance of glaciovolcanic caves in the hydrothermal cycle of volcanic systems, the global fight against antibiotic resistance, and their implications for understanding volcano-ice interactions beyond Earth, research on these systems is expanding. Kamchatka, Alaska, and Iceland have notable potential for further studies, while known research sites still hold open questions, including better understanding of the environmental parameters affecting cave genesis and persistence, the effect of glaciovolcanic cave development on underlying hydrothermal systems, and cataloging the biodiversity of glaciovolcanic cave environments. [ABSTRACT FROM AUTHOR]

This article provides an overview of Indian research efforts in Antarctic geoscience, focusing on various regions such as Schirmacher Oasis, Larsemann Hills, Prydz Bay, Princess Elizabeth Land, and the Amery Ice Shelf Region. The research has contributed to understanding the geological history, tectonic configuration, and paleoclimate of Antarctica. The article also highlights the significance of coal seams in the Permo-Triassic sedimentary sequence for correlation with coal belts in India. Geophysical studies, ice core drilling, and sediment coring have aided in this research. The article also discusses the role of the polar ice sheet in modulating atmospheric and ocean circulations, as well as the retreat of the East Antarctic Ice Sheet and the deposition of moraines in the Schirmacher Oasis. The Schirmacher Oasis and Larsemann Hills are notable ice-free areas that contain meltwater lakes, providing evidence of climate variation and deglaciation. These findings contribute to understanding the geological evolution and processes of East Antarctica. [Extracted from the article]

Detailed knowledge of Holocene climate and glaciers dynamics is essential for sustainable development in warming mountain regions. Yet information about Holocene glacier coverage in the Alps before the Little Ice Age stems mostly from studying advances of glacier tongues at lower elevations. Here we present a new approach to reconstructing past glacier low stands and ice-free conditions by assessing and dating the oldest ice preserved at high elevations. A previously unexplored ice dome at Weißseespitze summit (3500 m), near where the "Tyrolean Iceman" was found, offers almost ideal conditions for preserving the original ice formed at the site. The glaciological settings and state-of-the-art micro-radiocarbon age constraints indicate that the summit has been glaciated for about 5900 years. In combination with known maximum ages of other high Alpine glaciers, we present evidence for an elevation gradient of neoglaciation onset. It reveals that in the Alps only the highest elevation sites remained ice-covered throughout the Holocene. Just before the life of the Iceman, high Alpine summits were emerging from nearly ice-free conditions, during the start of a Mid-Holocene neoglaciation. We demonstrate that, under specific circumstances, the old ice at the base of high Alpine glaciers is a sensitive archive of glacier change. However, under current melt rates the archive at Weißseespitze and at similar locations will be lost within the next two decades. [ABSTRACT FROM AUTHOR]

The limitations and misjudgment of the duplicate checking software are presented by analyzing the duplicate checking of typical manuscripts. Problems of the irresponsible editors were pointed out in the process of preliminary examination of manuscripts. The significance and strategy of contemporary editors to regain the principles of "Three-Fair" (openness, fairness and justice) are elaborated based on the "real genius" paper from Journal of Glaciology and Geocryology and the famous "Pan Chang war" in the last century. [ABSTRACT FROM AUTHOR]

B Replying to b Rott et al. I Nature Communications i 10.1038/s41467-020-16658-y (2020) In Tuckett et al.[1], we report short-term speed-up events of Antarctic Peninsula outlet glaciers. Here, we defend the meltwater hypothesis, present evidence against the sea-ice hypothesis, and examine potential bias in our glacier velocity measurements. Although sea-ice evacuation is coincident with the March 2018 speed-up event observed in Tuckett et al.[1], changes in sea-ice characteristics are not synchronous across all studied glaciers. Finally, the sea-ice hypothesis cannot explain how glaciers return to pre-event velocities[1], as the sea ice does not rapidly reform to its pre-breakup structure (Fig. [Extracted from the article]

The analysis of satellite images revealed by 25% decrease of the Altai mountains' glaciation area over last 50 years. In 2008–2017, deglaciation rate increased twice. This tendency is in good agreement with an observed increase in the Katun River flow by 9% in 2008–2017 as compared to 1940–1968 (under invariable total precipitation). The analysis of trends of main meteorological parameters based on weather station data and the ERA-Interim reanalysis demonstrated that statistically significant warming in the region occurs only during the warm season and does not exceed 0.5°С/10 years. For this reason, "atmosphere–glaciers" turbulent heat transfer has increased by 4 W/m2 in last two years, that caused an annual melting layer increase by 100 mm water equivalent (w.e.). However, the main reason for the Altai mountains' deglaciation is an increase of downward solar radiation flux, which amounted to 5 W/m2 per decade and increased the melting layer by 365 mm w.e. per year. A positive trend in net radiation agrees well with a decrease in cloud amount, which is associated with an increase in the moisture divergence flux and geopotential height and with the weakening of zonal winds in the middle troposphere. [ABSTRACT FROM AUTHOR]

Supraglacial deposits of tephra or volcaniclastics have the potential to cause significant anomalies of glacier ablation and runoff. The intensity of these anomalies is governed by the thermal resistivity of the covering layer and hence the thermal conductivity of the deposited grains. This study concentrates on causal and quantitative relationships between density, geochemical composition and thermal conductivity of volcanic materials based on the analysis of 43 samples from locations across Iceland. Thermal conductivity is primarily influenced by density, whereas geochemical composition has been proved to be of subsidiary importance. Four different multiple regression models were calibrated that calculate the grain thermal conductivity of a volcanic material based on rock properties and geochemical composition. In a subsequent step, the bulk thermal conductivity of the respective deposit is calculated as a function of porosity and degree of water saturation. Examples using volcanic material from the Eyjafjallajökull 2010 and Grímsvötn 2011 eruptions confirm that the presented calculation scheme can be executed using only limited geochemical data as input. This facilitates an easy application of the modeling scheme immediately after a volcanic eruption. [ABSTRACT FROM AUTHOR]

Glaciers are highly effective agents of erosion that have profoundly shaped Earth's surface, but there is uncertainty about how glacial erosion should be parameterised in landscape evolution models. Glacial erosion rate is usually modelled as a function of glacier sliding velocity, but the empirical basis for this relationship is weak. In turn, climate is assumed to control sliding velocity and hence erosion, but this too lacks empirical scrutiny. Here, we present statistically robust relationships between erosion rates, sliding velocities, and climate from a global compilation of 38 glaciers. We show that sliding is positively and significantly correlated with erosion, and derive a relationship for use in erosion models. Our dataset further demonstrates that the most rapid erosion is achieved at temperate glaciers with high mean annual precipitation, which serve to promote rapid sliding. Precipitation has received little attention in glacial erosion studies, but our data illustrate its importance. Glaciers have profoundly shaped Earth's surface, but glacial erosion models lack a strong empirical basis. Cook et al. have compiled a dataset that illustrates how the speed at which glaciers move controls the rate at which they erode, and that climate is crucial in modulating glacier sliding speed and erosion rates. [ABSTRACT FROM AUTHOR]

The icy satellites of Jupiter and Saturn are perhaps the most promising places in the Solar System regarding habitability. However, the potential habitable environments are hidden underneath km-thick ice shells. The discovery of Enceladus' plume by the Cassini mission has provided vital clues in our understanding of the processes occurring within the interior of exooceans. To interpret these data and to help configure instruments for future missions, controlled laboratory experiments and simulations are needed. This review aims to bring together studies and experimental designs from various scientific fields currently investigating the icy moons, including planetary sciences, chemistry, (micro-)biology, geology, glaciology, etc. This chapter provides an overview of successful in situ, in silico, and in vitro experiments, which explore different regions of interest on icy moons, i.e. a potential plume, surface, icy shell, water and brines, hydrothermal vents, and the rocky core. [ABSTRACT FROM AUTHOR]

The polar regions are host to fundamental unresolved challenges in Earth studies. The nature of these regions necessitates the use of geophysics to address these issues, with electromagnetic and, in particular, magnetotelluric studies finding favour and being applied over a number of different scales. The unique geography and climatic conditions of the polar regions means collecting magnetotelluric data at high latitudes, which presents challenges not typically encountered and may result in significant measurement errors. (1) The very high contact resistance between electrodes and the surficial snow and ice cover (commonly MΩ) can interfere with the electric field measurement. This is overcome by using custom-designed amplifiers placed at the active electrodes to buffer their high impedance contacts. (2) The proximity to the geomagnetic poles requires verification of the fundamental assumption in magnetotellurics that the magnetic source field is a vertically propagating, horizontally polarised plane wave. Behaviour of the polar electro-jet must be assessed to identify increased activity (high energy periods) that create strong current systems and may generate non-planar contributions. (3) The generation of 'blizstatic', localised random electric fields caused by the spin drift of moving charged snow and ice particles that produce significant noise in the electric fields during periods of strong winds. At wind speeds above ~ 10 m s−1, the effect of the distortion created by the moving snow is broad-band. Station occupation times need to be of sufficient length to ensure data are collected when wind speed is low. (4) Working on glaciated terrain introduces additional safety challenges, e.g., weather, crevasse hazards, etc. Inclusion of a mountaineer in the team, both during the site location planning and onsite operations, allows these hazards to be properly managed. Examples spanning studies covering development and application of novel electromagnetic approaches for the polar regions as well as results from studies addressing a variety of differing geologic questions are presented. Electromagnetic studies focusing on near-surface hydrologic systems, glacial and ice sheet dynamics, as well as large-scale volcanic and tectonic problems are discussed providing an overview of the use of electromagnetic methods to investigate fundamental questions in solid earth studies that have both been completed and are currently ongoing in polar regions. [ABSTRACT FROM AUTHOR]

In this paper, we extend and analyze a Bayesian hierarchical spatiotemporal model for physical systems. A novelty is to model the discrepancy between the output of a computer simulator for a physical process and the actual process values with a multivariate random walk. For computational efficiency, linear algebra for bandwidth limited matrices is utilized, and first-order emulator inference allows for the fast emulation of a numerical partial differential equation (PDE) solver. A test scenario from a physical system motivated by glaciology is used to examine the speed and accuracy of the computational methods used, in addition to the viability of modeling assumptions. We conclude by discussing how the model and associated methodology can be applied in other physical contexts besides glaciology. [ABSTRACT FROM AUTHOR]

The results of measurements of the area of surging glaciers in 1974 and 2018 are compared to the data on their areas in 1913. A large decadal (middle-term) variability in the area of basin glaciation is revealed, and it is comparable to the respective secular (long-term) changes. It is shown that in, the southern meridional circulation epoch, despite high summer temperatures, the surging glaciers in the Sugran River basin grew in area due to increased precipitation, supporting the idea about their flood-runoff nature. [ABSTRACT FROM AUTHOR]

To improve our knowledge of glacier change in the Tanggula Mountains located in the northeast of the Tibetan Plateau, we delineated outlines of the glaciers in 1991 and 2015 using Landsat TM/OLI images and compared them with the reported glacier data in the First Chinese Glacier Inventory in 1969 and the Second Chinese Glacier Inventory in 2007. These comparisons showed that the glacier area and ice volume decreased by 524.8 km2 and 37 km3, respectively. The majority of the glacier area loss was concentrated in the area class of 1–5 km2, between 5300 m and 5500 m in elevation, on north and east facing slopes and in the Dam Qu River basin. These glacier changes exhibited spatial and temporal differences. The glacier retreat rate gradually increased from 1969 to 2015, and the rate in the east was higher than that in the west. From 1969 to 2015, the warming rate in the Tanggula Mountains was 0.38°C/10a, while the annual precipitation only increased by 0.4%. The slight increase in the amount of precipitation made a limited contribution to glacier change, while the change in temperature led to noticeable shrinkage of the glaciers. Contrary to the retreat or stagnation of most glaciers in the study area, there were 10 glaciers that experienced clear advance in 1986–2015 with noticeable increases in both area and length. Whether or not these 10 glaciers are surge glaciers requires further study. [ABSTRACT FROM AUTHOR]

The dynamics of radial wood increments have been analyzed according to the three tree-ring chronologies ALT (1463–2017), TUV (1715–2012), and MON (1663–2017) obtained for the southern regions of the Altai Mountains, southwestern regions of Tuva, and northern regions of Mongolian Altai, respectively. Chronologies demonstrate similar annual and long-term temporal variability. Cyclic changes in wood growth with periods of 10–14 and 29–33 years have been revealed. The limiting factor of growth is the air temperature in June–July (r > 0.7). At the same time, the chronologies are sensitive to the variation in circulatory, hydrological and glaciological parameters. [ABSTRACT FROM AUTHOR]

Glacier runoff shows significant change under global warming in the headwater region of the Indus River with great impact on its highly populated downstream area, but the hydrochemistry characteristics of meltwater and the changing mechanism remain unclear in this region. In this study, runoff water samples were collected during May and June, 2015, from four glacial catchments in the Upper Indus Basin to investigate general characteristics and daytime dynamics of meltwater runoff together with sediment and chemical contents. Results showed that glacier runoff in the studied area had an alkaline pH and much higher sediment yields than the local average of the non-glacier areas. The carbonate-dominated geological feature in the four catchments resulted in single chemical facies of Ca–HCO3. The dominant process determining the glacier runoff chemistry was rock-water interaction, with less soluble minerals and less intensive evaporate weathering in the Passu and Gulmit catchments than the B&B and Hinarchi catchments. Comparing the investigated catchments, the larger glacier with longer flow path exhibited higher runoff but lower melting rate, higher SSC resulting from higher erosive power of flow, and higher solute concentrations as a consequence of more intensive contact of meltwater with rock minerals along the longer flow path. For individual catchments, a negative correlation between TDS and flow rate (R2 = 0.26~0.53) and changing trends of ion ratios with flow rate demonstrated that under intensive melting conditions, rock-water interactions were reduced, resulting in dilution of solutes. Overall, the general chemical characteristics of the investigated glacier runoff indicated geological control, whereas individual glacier illustrated hydrological control on the daytime dynamics of glacier runoff chemistry. The presence of glacier terminal lake and agriculture land can significantly alter the hydrochemistry of downstream runoff. [ABSTRACT FROM AUTHOR]

A large numbers of mountain communities in the Himalayan region depend on glacier-fed kuhl system - gravity flow irrigation, for their sustenance. The depletion and retreat of glaciers often result in disruption of melt flows to kuhl system, which ultimately impacts the agriculture as well as livelihood of the local communities. Sustainability of glacial resource was assessed for establishing kuhl irrigation system based on indices of glacier decrease by number (GDN) and glacier depletion by volume (GDV) during the 2001–2013 period. The selected factors are important in terms of understanding point source and reserve potential of glaciers for sustaining glacier-fed kuhl irrigation in this region. The sustainability of glaciers was found good (i.e. a least decrease or rather increase in glacier number and volume) in about 23.6% glaciers (ice reserves about 705.9 km3) under >10 km2 area class of glaciers mainly in Gilgit and Shigar river basins of the Karakoram range. In the 5–10 km2 class of glaciers, sustainability was good in 49 glaciers (ice reserve 26.59 km3) and under 1–5 km2 class, in 558 glaciers (ice reserve 60.189 km3). Overall sustainability of glaciers appears to prevail in the Karakoram basins. The lesser sustainability of glaciers in the Himalaya basins like Astore and Jhelum would apparently be compensated by monsoon and change in rainfall pattern. A regular monitoring of the glacier resource and utilizing advance water conservation techniques would help in coping with negative impacts of down-wasting of glaciers and provide long-term support to kuhl irrigation system in the Himalayan region in future. [ABSTRACT FROM AUTHOR]

Investigations at a construction site in Hamburg (NW Germany) exposed palaeoseismic structures from moderate to strong earthquakes. Based on the large size of large blowout clastic dykes being up to 2.0 m wide and 2.5 m high, as well as the occurrence of infill structures, erratics/rafts of up to 9 kg in weight, seismites s.s. and decimetre-scale folds or seismoslumps, the magnitude of the earthquakes could be in the order of up to M ≥ 6. This is significantly higher than previously assumed for prehistorical seismic events in NW Germany. The structures are assigned to earthquakes possibly related to NW–SE-oriented faults that are evident in Lidar and SAR surface interpretations. Organic material from blowout-related infill bowls, assumed to be synchronously formed collapse depressions, are analysed for 14C ages. The dates reveal ages between 31,500 and 1200 14C cal a BP, indicating five prehistoric earthquakes. Accordingly, three of these earthquakes occurred before and after the main Weichselian glaciation phase (ca. 31,350, 26,850 and 18,980 14C cal a BP), and two occurred during the Subatlantic (ca. 4900 and 1200 14C cal a BP). The Weichselian events indicate seismic activity in the ice marginal zone during or following interstadials/Dansgaard–Oeschger events, as well as suggesting that advancing ice sheets foster earthquakes. [ABSTRACT FROM AUTHOR]

The environmental, socioeconomic and cultural significance of glaciers has motivated several countries to regulate activities on glaciers and glacierized surroundings. However, laws written to specifically protect mountain glaciers have only recently been considered within national political agendas. Glacier Protection Laws (GPLs) originate in countries where mining has damaged glaciers and have been adopted with the aim of protecting the cryosphere from harmful activities. Here, we analyze GPLs in Argentina (approved) and Chile (under discussion) to identify potential environmental conflicts arising from law restrictions and omissions. We conclude that GPLs overlook the dynamics of glaciers and could prevent or delay actions needed to mitigate glacial hazards (e.g. artificial drainage of glacial lakes) thus placing populations at risk. Furthermore, GPL restrictions could hinder strategies (e.g. use of glacial lakes as reservoirs) to mitigate adverse impacts of climate change. Arguably, more flexible GPLs are needed to protect us from the changing cryosphere. [ABSTRACT FROM AUTHOR]

Whereas the termini of Hektoria and Green glaciers extend into a wide bay, the tongues of the other studied glaciers are narrower and laterally confined by mountain ridges. GLL - Location of the grounding line; CST - glacier front in 2011, 2013, 2016. c and d: Sections of Sentinel-1 image of 2017-04-01 showing the location of the velocity transects on Hektoria Glacier (c) and Crane Glacier (d). The Larsen outlet glaciers have cold snow/ice bodies in which a substantial portion of the meltwater released at the surface would freeze, in particular after cold periods[7]. [Extracted from the article]

We investigate the accuracy and robustness of one of the most common methods used in glaciology for finite element discretization of the 픭-Stokes equations: linear equal order finite elements with Galerkin least-squares (GLS) stabilization on anisotropic meshes. Furthermore, we compare the results to other stabilized methods. We find that the vertical velocity component is more sensitive to the choice of GLS stabilization parameter than horizontal velocity. Additionally, the accuracy of the vertical velocity component is especially important since errors in this component can cause ice surface instabilities and propagate into future ice volume predictions. If the element cell size is set to the minimum edge length and the stabilization parameter is allowed to vary non-linearly with viscosity, the GLS stabilization parameter found in literature is a good choice on simple domains. However, near ice margins the standard parameter choice may result in significant oscillations in the vertical component of the surface velocity. For these reasons, other stabilization techniques, in particular the interior penalty method, result in better accuracy and are less sensitive to the choice of stabilization parameter. During this work, we also discovered that the manufactured solutions often used to evaluate errors in glaciology are not reliable due to high artificial surface forces at singularities. We perform our numerical experiments in both FEniCS and Elmer/Ice. [ABSTRACT FROM AUTHOR]

Glacier mass balance shows a spatially heterogeneous pattern in response to global warming on the Tibetan Plateau (TP), and the climate mechanisms controlling this pattern require further study. In this study, three glaciers where systematic glaciological and meteorological observations have been carried out were selected, specifically Parlung No. 4 (PL04) and Zhadang (ZD) glaciers on the southern TP and Muztag Ata No. 15 (MZ15) glacier in the eastern Pamir. The characteristics of the mass and energy balances of these three glaciers during the periods between October 1th, 2008 and September 23rd, 2013 were analyzed and compared using the energy and mass balance model. Results show that differences in surface melt, which mainly result from differences in the amounts of incoming longwave radiation (Lin) and outgoing shortwave radiation (Sout), represent the largest source of the observed differences in mass balance changes between PL04 and ZD glaciers and MZ15 glacier, where air temperature, humidity, precipitation and cloudiness are dramatically different. In addition, sensitivity experiments show that mass balance sensitivity to air temperature change is remarkably higher than that associated with precipitation change on PL04 and ZD glaciers, in contrast results from MZ15 glacier. And significantly higher sensitivities to air temperature change are noted for PL04 and ZD glaciers than for MZ15 glacier. These significant differences in the sensitivities to air temperature change are mainly caused by differences in the ratio of snowfall to precipitation during the ablation season, melt energy (Lin+Sout) during the ablation season and the seasonality of precipitation among the different regions occupied by glaciers. In turn, these conditions are related to local climatic conditions, especially air temperature. These factors can be used to explain the different patterns of change in Tibetan glacier mass balance under global warming. [ABSTRACT FROM AUTHOR]

The cumulative effect of repeated extensive glaciations represents a poorly constrained component in the understanding of landscape evolution in mid-latitude mountain ranges such as the Alps. Timing, extent, and paleo-climatic conditions of these glaciations are generally poorly understood due to the often-fragmentary character of terrestrial Quaternary records. In this context, the sedimentary infills of subglacial basins may serve as important archives to complement the Quaternary stratigraphy over several glacial-interglacial cycles. In this study, sedimentary facies, valley-fill architecture, and luminescence dating are used to describe nine erosional and depositional cycles (Formations A-I) in the Lower Glatt valley, northern Switzerland. These cycles can be related to the ‘Birrfeld’ Glaciation (~ MIS2), the ‘Beringen’ Glaciation (~ MIS6), and up to three earlier Middle Pleistocene glaciations that can be tentatively correlated to the regional glaciation history. Evidence suggests that deep bedrock trough incision and/or partial re-excavation last occurred mainly during the ‘Beringen’ and ‘Habsburg’ Glaciations. Second-order, ‘inlaid’ glacial basins document separate glacier re-advances during the Beringen Glaciation. The arrangement of subglacial basins in the Glatt valley with different sub-parallel or bifurcating bedrock troughs, re-excavated segments, and inlaid basins document changes in the magnitude and the spatial focus of subglacial erosion over time. The Glatt valley may thus serve as a key example for the glacial landscape evolution in many other repeatedly glaciated forelands. [ABSTRACT FROM AUTHOR]

Very few exact solutions are known for the non-linear Vialov ordinary differential equation describing the longitudinal profiles of alpine glaciers and ice caps under the assumption that the ice deforms according to Glen's constitutive relationship. Using a simple, yet wide, class of models for the accumulation rate of ice and Chebysev's theorem on the integration of binomial differentials, many new exact solutions of the Vialov equations are obtained in terms of elementary functions. [ABSTRACT FROM AUTHOR]

Glacier length is a key morphological element that has many glaciological applications; however, it is often difficult to determine, especially for glaciers that cover larger spatial areas or those that exhibit frequent temporal change. In this paper, we describe a new ArcGIS-based method that can derive glacier flow lines for determining glacier length based on digital elevation model and glacier outlines. This method involves (1) extraction of the highest and lowest points on a glacier, (2) calculation of 10-m contour lines on the glacier from 10 m to 100 m height, and (3) connection of the midpoints of each contour line with the highest and the lowest points in order to create a flow line, which is subsequently smoothed. In order to assess the reliability of this method, we tested the algorithm's results against flow lines calculated using field measurements, analysing data from the Chinese Glacier Inventory, and manual interpretation. These data showed that the new automated method is effective in deriving glacier flow lines when contour lines are relatively large; in particular, when they are between 70 m and 100 m. Nonetheless, a key limitation of the algorithm is the requirement to automatically delete repeated and closed curves in the pre-treatment processes. In addition to calculating glacier flow lines for derivation of glacier length, this method also can be used to effectively determine glacier terminus change. [ABSTRACT FROM AUTHOR]

In view of the recent global changes in the hydrological, glaciological, agricultural, socio-economic studies, etc., particularly, over the northern Indian region, Indian winter (December, January, February-DJF) monsoon (IWM) has important role. Geographical positioning of the Indian subcontinent having mighty Himalayas in the north and surrounding ocean in the south makes assessment of IWM important and interesting to study. During IWM, the western Himalayas (WH) receives almost one-third of annual precipitation due to eastward moving extratropical cyclonic storms, western disturbances (WDs), embedded within the large scale subtropical westerly jet (SWJ). In addition, IWM is found to be in phase with the El Niño-Southern Oscillation (ENSO). With reference to the recent decade's finding of having different phases of El Niño- warm pool (WP) and cold tongue (CT)-it is imperative to see how these phases affect IWM. In the present study a simple mechanism between IWM with different phases of these El Niño and their relationship is studied and deliberated upon. WP and CT El Niño phase composites are prepared and their corresponding role in tandem with IWM is provided. It is found that during WP (CP) El Niño phase WH (foothill of the Indian Himalayan) region receives higher amount of winter precipitation. It is attributed to the fact that equatorial central Pacific warming makes more conducive proposition for intensification of the WDs and thus associated higher precipitation over western part of the Indian Himalayas. Northward shift of confluence over northern Atlantic region during WP El Niño phase dampens the SWJ leading to longer residence time for weather events-WDs-over the WH region. In addition, strengthening of Hadley cell leads to higher northward transport of moisture from the Indian Ocean region. [ABSTRACT FROM AUTHOR]

This study is concerned with numerical simulation of the strain due to glaciation and glacial melting, when a magma zone (a layer containing inclusions of magma and magma cumulates) is present at the crust-mantle boundary. According to analytical solutions of this problem that involves viscous relaxation of an uncompensated depression at the place of the molten glacier, the depth to the zone of increased shear stresses beneath the depression is proportional to its width, while the relaxation duration is proportional to viscosity of the lithosphere and is a few thousand years. These fundamental estimates are corroborated by our numerical simulation. According to it, the magma zone at the Moho boundary shields the zone of increased shear stresses, limiting it from below. The maximum values (12-25 MPa) with glacial thickness 500-1000 m are reached at the top of this layer of low viscosity. The directions of maximum compression (s) as calculated for the time after the melting indicate that the magma that rises along dikes is displaced from the center of the magma lens toward its periphery. It is found that glacial unloading makes the dipping faults in the crust above the low-viscosity layer attractors for the rising magma. Glacial unloading accelerates, by factors of a few times, the magma generation in the mantle that occurs following the mechanism of adiabatic decompression, as well as facilitating the accumulation of mantle fluids in the zone of increased shear stresses at the boundary of the low viscosity layer. The magma traverses this deep fluid collector and increases the intensity and explosivity of eruptions at the beginning of an interglacial period. Our numerical simulation results are in general agreement with published data on Early Holocene volcanic eruptions that occurred after the second phase of the Late Pleistocene glaciation in Kamchatka. [ABSTRACT FROM AUTHOR]

In this paper we provide a literature review of the geological and geographic problems that were successfully solved via the application of the Gravity Recovery And Climate Experiment (GRACE) satellite mission data. GRACE is a gravitational satellite mission whose purpose is the precise mapping of variations of the Earth's gravity field. The data have high resolution, which provides the opportunity to solve many geological and geographical problems. [ABSTRACT FROM AUTHOR]

Poor bleaching is a significant problem for Optically Stimulated Luminescence (OSL) dating of glacial sediments. Five young glacial samples (including two modern analogues) from different depositional settings were collected beyond the Yingpu Glacier in the eastern Qinghai-Tibetan Plateau. De was determined using different OSL methods. The luminescence characteristics and dating results showed that the large aliquot quartz Blue Stimulated Luminescence (BSL) is more applicable than polymineral infrared stimulated luminescence (IRSL) method. Small aliquot quartz BSL results showed poor luminescence properties due to low luminescence sensitivity of quartz in this area. The dating results also indicated that glaciofluvial samples deposited close to ice margin (~40 m and ~700 m) and supraglacial debris dominated lateral moraine samples are relatively well-bleached, whereas samples from ground moraine and low terminal moraine were poorly bleached, probably due to containing subglacial and englacial debris. The residual doses of glaciofluvial and lateral moraine crest samples were below a few Gy and age overestimations were below a few hundred years. The ground moraine and low terminal moraine samples had residual doses as high as ~110 Gy, and ages were overestimated by ~15-17 ka. [ABSTRACT FROM AUTHOR]

The Greenland ice sheet is a very important potential source of fresh water inflow to the World Ocean under warming climate conditions. Apparently, it was the same during the Last Interglacial 130-115 thousand years ago. In order to quantify input of the Greenland ice sheet to the rise of the global mean sea level in the past or in the future, we include a surface mass balance model block into the Earth System Model. The computational algorithm is based on the calculation of energy balance on the ice sheet surface. The key tuning parameter of the model is the daily amplitude of air surface temperature. It defines the area and the rate of snow or ice melting. The range of possible values of this parameter is determined during a series of numerical experiments. High sensitivity of meltwater runoff volume to surface air temperature amplitude is revealed. [ABSTRACT FROM AUTHOR]

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Changes in glacial geometries (extent and surface elevations) in the Ayilariju region of Western Himalaya, China, were investigated using topographical maps and data from the Landsat Thematic Mapper/Enhanced Thematic Mapper Plus, the Satellite Pour l'Observation de la Terre (SPOT4), the Shuttle Radar Topography Mission 4.1 digital elevation model, and geographical information system techniques. The results showed that the total glaciated area decreased from 190.37 to 162.52 km (14.6 % of the 1980 glaciated area) from 1980 to 2011. Furthermore, total glacial mass loss of studied region was estimated to be 2.570 ± 0.327 km between 1980 and 2000. Further investigation on meteorological data indicated that increases of temperature and total radiation were the primary causes of accelerated glacial melting. Reduced wind speed and slight decreases in precipitation triggered by weakening of the South Asian summer monsoon due to warming, may also have contributed to glacial shrinkage. The rate of glacial retreat in the studied region is lower than that in the southern Himalayan region, but larger than that in the Karakoram, primarily because Ayilariju glaciers were located on the margin of the Indian monsoon dominated region. [ABSTRACT FROM AUTHOR]

According to the European Union Water Framework Directive groundwater and surface-water resources have to be managed in an integrated way. The utilisation of groundwater resources must not harm surface-water ecosystems that are directly dependent on groundwater. The study evaluates the effects of increased groundwater abstraction (a) on a regional scale to groundwater and lake levels in a lake district, and (b) on a local scale to the seepage patterns in one example lake. After a 51 % increase in the pumping rates from an unconfined aquifer the water levels of three closed-basin lakes near the intake fell 0.3-0.7 m in 1 year, but did not change in the two lakes further from the intake. Groundwater levels in the aquifer dropped up to 0.8 m near the intake, but did not change further from the wells. Seepage measurements at the bottom of one lake showed that before the increased abstraction outseepage occurred in its northern side, after the increased abstraction the outseepage area had widened towards its western side. The results confirm that the groundwater level drop and the consequent lake-level drop were caused by the increased abstraction rate. The outcomes of the rare opportunity to analyse lake/groundwater interactions both before and after increased human intervention provide a cautionary example of what may happen to and in groundwater-dependent lakes if the groundwater/surface-water interactions are not fully clarified before the intervention in potentially similar cases around the world. [ABSTRACT FROM AUTHOR]

Changes in glaciers in the Daxue and Danghenan ranges were analyzed based on topographic maps, satellite images and a digital elevation model (DEM). The results indicate that from 1957/1966 to 2010, the total area and ice volume for the investigated glaciers declined by 17.21 and 24.10 % in these respective ranges. From 1957 to 2010, the total area and ice volume in the glaciers in the Daxue Range declined by 16.03 % (0.30 % a) and 22.40 %, respectively, with a mean reduction of 0.133 km for an individual glacier. These glaciers retreated by an average of 258 m (3.4 m a). From 1966 to 2010, the total area and ice volume for the glaciers in the Danghenan Range declined by 18.32 % (0.42 % a) and 25.70 %, with a mean reduction of 0.111 km for an individual glacier. These glaciers retreated by an average of 159 m (3.6 m a). The rate of glacier retreat on the south-facing slopes was faster than that on the north-facing slopes. The area of glaciers on the south and north slopes of the Daxue Range declined by 22.82 and 15.51 %, respectively, and the area of glaciers on the south and north slopes of the Danghenan Range declined by 22.39 and 16.76 %, respectively. An analysis of the general trend of climatic change in the study area revealed that rapidly rising air temperatures were most likely the major factor causing the loss of glacier ice within the study area. Compared with other glaciers in the eastern and middle Qilian Mountains, glaciers in the western Qilian Mountains appeared to be losing mass at a slower rate. The differences of glacier changes in the eastern, middle, and western Qilian Mountains are mainly caused by the combination of climatic conditions and glacier morphologic factors. [ABSTRACT FROM AUTHOR]

Progress in reconstructing the mechanism of the influence of drifting snow on changes in the ice surface elevation, when it moves with velocity of 2-5 m/year, was achieved owing to space-based laser altimetry and the discovery of fractal patterns of the elevation fluctuations. They consist in the growth of variance of elevation changes by an increased lag. The variance grows in the power law dependence in the scaling range of 70 km. The wavelet analysis revealed a wide spectrum of spatial frequencies and demonstrated that they occur in the range of 1.4-22.5 km. The discovered properties of changes in the surface elevation subordinate to the Gaussian distribution with zero mean indicate dynamic equilibrium of the present-day Antarctic ice sheet. [ABSTRACT FROM AUTHOR]

Damages from sea level rise, as well as strategies to manage the associated risk, hinge critically on the time scale and eventual magnitude of sea level rise. Satellite observations and paleo-data suggest that the Greenland Ice Sheet (GIS) loses mass in response to increased temperatures, and may thus contribute substantially to sea level rise as anthropogenic climate change progresses. The time scale of GIS mass loss and sea level rise are deeply uncertain, and are often assumed to be constant. However, previous ice sheet modeling studies have shown that the time scale of GIS response likely decreases strongly with increasing temperature anomaly. Here, we map the relationship between temperature anomaly and the time scale of GIS response, by perturbing a calibrated, three-dimensional model of GIS behavior. Additional simulations with a profile, higher-order, ice sheet model yield time scales that are broadly consistent with those obtained using the three-dimensional model, and shed light on the feedbacks in the ice sheet system that cause the time scale shortening. Semi-empirical modeling studies that assume a constant time scale of sea level adjustment, and are calibrated to small preanthropogenic temperature and sea level changes, may underestimate future sea level rise. Our analysis suggests that the benefits of reducing greenhouse gas emissions, in terms of avoided sea level rise from the GIS, may be greatest if emissions reductions begin before large temperature increases have been realized. Reducing anthropogenic climate change may also allow more time for design and deployment of risk management strategies by slowing sea level contributions from the GIS. [ABSTRACT FROM AUTHOR]

Populations in Central Asia are heavily dependent on snow and glacier melt for their water supplies. Changes to the glaciers in the main mountain range in this region, the Tien Shan, have been reported over the past decade. However, reconstructions over longer, multi-decadal timescales and the mechanisms underlying these variations-both required for reliable future projections-are not well constrained. Here we use three ensembles of independent approaches based on satellite gravimetry, laser altimetry, and glaciological modelling to estimate the total glacier mass change in the Tien Shan. Results from the three approaches agree well, and allow us to reconstruct a consistent time series of annual mass changes for the past 50 years at the resolution of individual glaciers. We detect marked spatial and temporal variability in mass changes. We estimate the overall decrease in total glacier area and mass from 1961 to 2012 to be 18 ± 6% and 27 ± 15%, respectively. These values correspond to a total area loss of 2,960 ± 1,030 km2, and an average glacier mass-change rate of −5.4 ± 2.8 Gt yr−1. We suggest that the decline is driven primarily by summer melt and, possibly, linked to the combined effects of general climatic warming and circulation variability over the north Atlantic and north Pacific. [ABSTRACT FROM AUTHOR]

The contributions of Italian Geodesy to sciences which have different objectives and methods are briefly outlined. They concern Hydraulics, Glaciology, Photogrammetry, shielding of gravitation, Geology, Astronomy and the theory of measures. [ABSTRACT FROM AUTHOR]

Recent keen interest to ancient glacial sediments is caused by important issues: first, striving to understand causes and scales of climate changes in the Earth in connection with the anticipated warming; second, understanding how glaciations and deglaciations affect biosphere and biota. Physical traces of ancient glaciations occur as glacial sediments. Identification of these sediments in pre-Pleistocene sections is a rather difficult task because of the convergent external appearance of glacial and some other sediments unrelated to glaciers. At present, tillite-type formations (diamicts) are not infrequently assigned to glacial sediments without a proper analysis of their lithology and facies associations. The paper presents a review of indicators used for the identification of glacial sediments and comparative assessment of their significance. It is emphasized that the presence of diamicts and finds of rocks with striations or clasts scattered in the thin-bedded rocks are quite insufficient for the identification of glacial sediments. Detailed descriptions and illustrations of indicators, as well as analysis of lateral and vertical facies associations of diamicts, are essential. In conclusion, the major diagnostic features of different facies of glacial sediments are listed. [ABSTRACT FROM AUTHOR]

Rock avalanches onto glacier surfaces, involving volumes 1 Mm or more, are common in the glacier environments of NW North America. We analyse the Mount Munday rock avalanche (British Columbia) which occurred in July 1997. It involved the initial movement of 3.2 Mm of granitic gneiss that underwent a high degree of fragmentation as it was emplaced on Ice Valley Glacier as a thin 2.6-km debris sheet. The total height of the path was 850 m, and its length was 4,163 m yielding a fahrböschung of 10°, suggestive of a long runout in relation to volume. Potential energy expended in the movement was calculated as 4.33 × 10 J and its specific energy was estimated at 5,204 J/kg. A simulation of the movement using 2D DAN-W and DAN 3D strongly supports the idea that debris sheet geometry (runout and thickness) and behaviour (velocity profile) resulted from movement on a low friction surface (glacier ice). Our analysis of the debris sheet geometry of 23 unconstrained rock avalanches on glacier surfaces in NW North America indicated that the debris sheets are distinct from those in non-glacial environments in that they are (a) longer in relation to volume and (b) more extensive in area in relation to volume. These two effects result in a very thin supra-glacial debris sheet. Using image analysis software, we found that ∼85 % of the initial source rock volume was fragmented to fragment sizes less than 4.7 m in volume during emplacement, and that within the debris sheet, the highest degree of fragmentation is associated with the thinnest debris. In the emplacement of rock avalanche debris sheets on glacier surfaces, the low friction glacier surface drives debris sheet thinning through spreading, which in turn results in the fragmentation of its entire thickness. We thus propose low friction surface-driven fragmentation as a process that contributes to long runout of rock avalanches on glacier surfaces and explains their distinctive debris sheet geometry. [ABSTRACT FROM AUTHOR]

The anthropogenic changes of permafrost are studied at the key sites in the European North, i.e., Koida Village (Mezen' tundra), Nes' Village (Kanin Peninsula), Shoina Village (Kanin Peninsula), Mezen' Town, Vashutkiny Lakes (Bol'shezemel'skaya tundra), Amderma (Yugorskii Peninsula), and the northern part of Vaigach island. Geocryological characteristics of the sites are provided, and the main types of anthropogenic changes in permafrost conditions are described. [ABSTRACT FROM AUTHOR]

The northern Antarctic Peninsula is currently undergoing rapid atmospheric warming. Increased glacier-surface melt during the twentieth century has contributed to ice-shelf collapse and the widespread acceleration, thinning and recession of glaciers. Therefore, glaciers peripheral to the Antarctic Ice Sheet currently make a large contribution to eustatic sea-level rise, but future melting may be offset by increased precipitation. Here we assess glacier-climate relationships both during the past and into the future, using ice-core and geological data and glacier and climate numerical model simulations. Focusing on Glacier IJR45 on James Ross Island, northeast Antarctic Peninsula, our modelling experiments show that this representative glacier is most sensitive to temperature change, not precipitation change. We determine that its most recent expansion occurred during the late Holocene 'Little Ice Age' and not during the warmer mid-Holocene, as previously proposed. Simulations using a range of future Intergovernmental Panel on Climate Change climate scenarios indicate that future increases in precipitation are unlikely to offset atmospheric-warming-induced melt of peripheral Antarctic Peninsula glaciers. [ABSTRACT FROM AUTHOR]

The article looks at a study done to investigate the reduction of Altai Glaciers in Russia and Kazakhstan. Topics discussed include characteristics of glaciation at several main glaciation centers and specified the terminal point positions including Big Taldura, Alakha and Sofiiskii; spatial structure of Alatai Glaciation; and evolution of concrete areas of glaciation in the ranges and their fractions.