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The mountains systems of Central Asia are primary targets to study late Pleistocene climate evolution given their location at the crossroads of several atmospheric circulation systems. The timing of glacier extent during this period remains understudied, especially in the Altai Mountains. Here, we have reconstructed glacier extent during three main Late Pleistocene stadials in the upper Kalguty basin (south‐eastern Russian Altai) based on field‐based geomorphic analysis. Additionally, surface exposure dating with 10Be and 26Al at a key site was used to infer a minimum‐limiting age for the outermost well‐preserved Pleistocene frontal moraine system and to date the inception of glacier withdrawal. According to our data, around 20.6 ± 1.8 ka Kalguty Glacier was still 200 m thick at the key site, 10 km upstream of the outermost moraine, and the site was totally deglaciated shortly after 20.4 ± 0.4 ka. These results point to a rapid retreat of this low‐gradient valley glacier after its probably MIS 2 maximum which was prior to 21 ka and probably prior to 22.5 ka. Two other glacier stages have been identified upvalley, characterized by a depression of the equilibrium‐line altitude of 420 and 314 m with respect to the Little Ice Age, thus corresponding to Lateglacial advances. Our glacier reconstruction further provides a geomorphological and geochronological background to put into context archaeological findings in this area. [ABSTRACT FROM AUTHOR]

Mountain glacier mass balance is affected by factors other than climate, such as topography, slope, and aspect. In midlatitude high-mountain regions, the north–south aspect contrast can cause significant changes in insolation and melt, resulting in local asynchrony in glacial dynamics. This study documents the asynchronous response of two paleoglaciers in southwestern Mongolia to the local topoclimatic factors using 10 Be exposure age dating and 2D ice surface modeling. 10 Be surface exposure age dating revealed that the Ikh Artsan south-facing valley glacier culminated (M IA1) at 20.1 ± 0.7 ka, coinciding with the global Last Glacial Maximum (gLGM). In contrast, the north-facing Jargalant paleoglacier (M J1) culminated at 17.2 ± 1.5 ka, around Heinrich Stadial 1 and during the post-gLGM Northern Hemisphere warming. Our temperature-index melt model predicts that ablation will be substantially lower on the north-facing slope, as it is exposed to less solar radiation and cooler temperatures than the south-facing slope. The 2D ice surface modeling also revealed that the south-facing Ikh Artsan Glacier abruptly retreated from its maximum extent at 20 ka, but the Jargalant Glacier on the shaded slope consistently advanced and thickened due to reduced melt until 17 ka. The timing of the modeled glacier culmination is consistent within ± 1 σ of the 10 Be exposure age results. Extremely old ages ranging from 636.2 to 35.9 ka were measured for the inner moraines in the Jargalant cirque (M J2 –M J4), suggesting a problem with inheritance from boulders eroded from the summit plateau. [ABSTRACT FROM AUTHOR]

Mt. Munkhkhairkhan is the most crucial region for understanding climate and glaciation changes in Mongolia. This study investigated the relationship between glacial area changes and the climate elements of Mt. Munkhkhairkhan in the Mongolian-Altai Mountains using a remote sensing approach, in-situ observations, the Mann–Kendall (MK) test, Innovative Trend Analysis Method (ITAM), Sen's slope estimator test, and statistical analysis. The study results showed that for the last 30 years, the annual average air temperature of Mt. Munkhkhairkhan has been slightly increasing. Total annual precipitation (mainly snow) in the mountain area decreased from 1990 to 2000, but since 2000, a significant increase in precipitation levels has appeared. For the last 30 years, the glacial area has decreased by 32% to 11.7 km2. Multiple regression results showed a strong correlation between Temperature, Precipitation, and Glaciers (Multiple R = 0.69, R2 = 0.48). Ruther indicated that Temperature (t = −2.332, p = 0.036) and Precipitation (t = −3.212, p = 0.007) were significant predictors in the model. Air temperature and precipitation explained 48 percent of the change in the glacier area, and R = 0.69 is a strong correlation. The glaciers and snow area in the study area have changed due to climate warming and precipitation changes and are located in arid and semi-arid regions of Central Asia. This study of Mt. Munkhairkhan shows that climate change significantly impacts glaciers and snow. [ABSTRACT FROM AUTHOR]

Melt-albedo feedback on glaciers is recognized as important processes for understanding glacier behavior and its sensitivity to climate change. This study selected the Muz Taw Glacier in the Altai Mountains to investigate the spatiotemporal variations in albedo and their linkages with mass balance, which will improve our knowledge of the recent acceleration of regional glacier shrinkage. Based on the Landsat-derived albedo, the spatial distribution of ablation-period albedo was characterized by a general increase with elevation, and significant east–west differences at the same elevation. The gap-filling MODIS values captured a nonsignificant negative trend of mean ablation-period albedo since 2000, with a total decrease of approximately 4.2%. From May to September, glacier-wide albedo exhibited pronounced V-shaped seasonal variability. A significant decrease in annual minimum albedo was found from 2000 to 2021, with the rate of approximately −0.30% yr−1 at the 99% confidence level. The bivariate relationship demonstrated that the change of ablation-period albedo explained 82% of the annual mass-balance variability. We applied the albedo method to estimate annual mass balance over the period 2000–2015. Combined with observed values, the average mass balance was −0.82 ± 0.32 m w.e. yr−1 between 2000 and 2020, with accelerated mass loss. [ABSTRACT FROM AUTHOR]

In the semiarid climate of northwestern Mongolia, glaciers are critical contributors to water resources, particularly during the dry summer months. Nevertheless, our knowledge of the contribution of glacier runoff in the Upper Khovd River Basin (UKRB) is limited. This study investigates the impact of glacier recession on the UKRB's hydrology in western Mongolia's Altai Mountains. The analysis included glaciological method measurements, satellite-derived glacier extent records, and a simple ice ablation model. Our modeling used a mass balance gradient of 0.50 meters water equivalent 100 m–1 for the years 2000, 2010, and 2016 and included a sensitivity analysis that applied lower and upper mass balance gradient values and ±200 m around the equilibrium line altitude (ELA). The glacier contribution to the UKRB's water resources decreased from almost 8% in 2000 to 6.7% in 2016. Hypsometries revealed that glacier areas decreased at all elevations, indicating that only small accumulation zones exist. Therefore, applying a modeled increased ELA better represents glacier contribution to total runoff, at 18.7% in 2000 and 15.4% in 2016. The decreasing glacier runoff contribution indicates that the UKRB glaciers have passed the tipping point of an increased contribution that first follows enhanced melting. The continued glacier recession and uncertain water availability represent challenges for water resource management and future human–water relations in the Mongolian Altai.

Based on numerical experiments undertaken with nine climate models, the glacier equilibrium line altitudes (ELAs) in western China during the last glacial maximum (LGM) are investigated to deepen our understanding of the surface environment on the Tibetan Plateau. Relative to the preindustrial period, the summer surface air temperatures decrease by 4–8°C while the annual precipitation decreases by an average of 25% across the Tibetan Plateau during the LGM. Under the joint effects of reductions in summer temperature and annual precipitation, the LGM ELAs in western China are lowered by magnitudes that vary with regions. The ELAs in the southern margin and northwestern Tibetan Plateau decline by approximately 1100 m; the central hinterland, by 650–800 m; and the eastern part, by 550–800 m, with a downward trend from southwest to northeast. The reduction in ELAs is no more than 650 m in the Tian Shan Mountains within China and approximately 500–600 m in the Qilian Mountains and Altai Mountains. The high-resolution models to reproduce the low values of no more than 500 m in ELA reductions in the central Tibetan Plateau, which are consistent with the proxy records from glacier remains. The accumulation zones of the Tibetan Plateau glaciers are mainly located in the marginal mountains during the LGM and have areas 2–5 times larger than those of the modern glaciers but still do not reach the central part. [ABSTRACT FROM AUTHOR]

In the semiarid climate of northwestern Mongolia, glaciers are critical contributors to water resources, particularly during the dry summer months. Nevertheless, our knowledge of the contribution of glacier runoff in the Upper Khovd River Basin (UKRB) is limited. This study investigates the impact of glacier recession on the UKRB's hydrology in western Mongolia's Altai Mountains. The analysis included glaciological method measurements, satellite-derived glacier extent records, and a simple ice ablation model. Our modeling used a mass balance gradient of 0.50 meters water equivalent 100 m–1 for the years 2000, 2010, and 2016 and included a sensitivity analysis that applied lower and upper mass balance gradient values and ±200 m around the equilibrium line altitude (ELA). The glacier contribution to the UKRB's water resources decreased from almost 8% in 2000 to 6.7% in 2016. Hypsometries revealed that glacier areas decreased at all elevations, indicating that only small accumulation zones exist. Therefore, applying a modeled increased ELA better represents glacier contribution to total runoff, at 18.7% in 2000 and 15.4% in 2016. The decreasing glacier runoff contribution indicates that the UKRB glaciers have passed the tipping point of an increased contribution that first follows enhanced melting. The continued glacier recession and uncertain water availability represent challenges for water resource management and future human–water relations in the Mongolian Altai. [ABSTRACT FROM AUTHOR]

The Altai Mountains contain 1281 glaciers covering an area of 1191 km 2 . These glaciers have undergone significant changes in glacial length and area over the past decade. However, mass changes of these glaciers and their impacts remain poorly understood. Here we present surface mass balances of all glaciers in the region for the period 1990–2011, using a glacier mass-balance model forced by the outputs of a regional climate model. Our results indicate that the mean specific mass balance for the whole region is about −0.69 m w.e. yr −1 over the entire period, and about 81.3% of these glaciers experience negative net mass balance. We detect an accelerated wastage of these glaciers in recent years, and marked differences in mass change and its sensitivity to climate change for different regions and size classes. In particular, higher mass loss and temperature sensitivity are observed for glaciers smaller than 0.5 km 2 . In addition to temperature rise, a decrease in precipitation in the western part of the region and an increase in precipitation in the eastern part likely contribute to significant sub-region differences in mass loss. With significant glacier wastage, the contribution of all glaciers to regional water resources and sea-level change becomes larger than before, but may not be a potential threat to human populations through impacts on water availability. [ABSTRACT FROM AUTHOR]

We project glacier surface mass balances of the Altai Mountains over the period 2006-2100 for the representative concentration pathway (RCP) 4.5 and RCP8.5 scenarios using daily near-surface air temperature and precipitation from 12 global climate models in combination with a surface mass balance model. The results indicate that the Altai glaciers will undergo sustained mass loss throughout the 21st for both RCPs and reveal the future fate of glaciers of different sizes. By 2100, glacier area in the region will shrink by 26 ± 10 % for RCP4.5, while it will shrink by 60 ± 15 % for RCP8.5. According to our simulations, most disappearing glaciers are located in the western part of the Altai Mountains. For RCP4.5, all glaciers disappearing in the twenty-first century have a present-day size smaller than 5.0 km, while for RCP8.5, an additional ~7 % of glaciers in the initial size class of 5.0-10.0 km also vanish. We project different trends in the total meltwater discharge of the region for the two RCPs, which does not peak before 2100, with important consequences for regional water availability, particular for the semi-arid and arid regions. This further highlights the potential implications of change in the Altai glaciers on regional hydrology and environment. [ABSTRACT FROM AUTHOR]

Glaciers in the Altai Mountains of Mongolia provide an estimated 11% of the total water resources within the country. Yet, their number and area in inconsistent. Using satellite imagery acquired from Landsat 4, 5, and 7, and SRTM digital elevation model (DEM) data, we present here an intuitive, robust, and inexpensive methodology to map the exposed ice of glaciers in the Altai Mountains for the period 1989 to 2011. The total glacierized area was 515 km2 in 1989/1991, 428 km2 in 1998/2001, and 372 km2 in 2010/2011; it decreased by 17% from 1989/1991 to 1998/2001, 13% from 1998/2001 to 2010/2011, and 28% for the entire period 1989/1991 to 2010/2011. In analyzing a sub-sample of 260 glaciers, 6% advanced, 11% were stable, and 83% receded from 1989 to 2011. The glacier dataset is available to the public free of charge at the Global Land Ice Measurements from Space (GLIMS) website. [ABSTRACT FROM AUTHOR]

Mountain glaciers are indicators of climate change and of current water resources. They are important ecological systems and can be used to support sustainable development of industry and agriculture. However, due to climate warming, most glaciers are in a state of rapid retreat. Using topographic maps in 1959, ASTER remote sensing data in 2008 and ASTER digital elevation models (DEMs), area, ice surface elevation, and volume changes of glaciers on the Friendship Peak in the Chinese Altai Mountains were analyzed. Results showed that the collective area of all 201 glaciers investigated was reduced by 30.4% from 1959 to 2008. Fifty-five glaciers disappeared entirely. The average rates of reduction in area of glaciers with sizes < 0.5, 0.5–1, 1–4, 4–10, and > 10 km 2 were 25.9%, 30.8%, 30.9%, 35.9%, and 27.4%, respectively. From 1959 to 2008, the elevation of the glacier surface decreased by 20 m at an average rate of 0.4 m a − 1 . For the Kanas Glacier, the changes in ice surface elevation ranged from − 101 to + 38 m. Results showed that glaciers at lower altitudes and smaller sizes experienced more extensive changes in elevation. The intensive glacier ablation over the Friendship Peak in the Altai Mountains was found to be caused by increases in the regional temperature, which occurred at an average rate of 0.52 °C per decade. [ABSTRACT FROM AUTHOR]

Mass loss of glaciers in the Chinese Altai was detected using geodetic methods based on topographical maps (1959), the Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) (2000), and the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) stereo images (2008). The results indicate that a continued and accelerating shrinkage has occurred in the Chinese Altai Mountains during the last 50 years, with mass deficits of 0.43 ± 0.02 and 0.54 ± 0.13 m a water equivalent (w.e.) during the periods 1959-1999 and 1999-2008, respectively. Overall, the Chinese Altai Mountains have lost 7.06 ± 0.44 km in ice volume (equivalent to −0.43 ± 0.03 m a w.e.) from 1959-2008. The spatial heterogeneity in mass loss was potentially affected by comprehensive changes in temperature and precipitation, and had a substantial correlation with glacier size and topographic settings. Comparison shows that in the Chinese Altai Mountains glaciers have experienced a more rapid mass loss than those in the Tianshan and northwestern Tibetan Plateau (TP), and the mass balance of glaciers was slightly less negative relative to those in the Russian Altai, Himalaya, and southern TP. [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.

The evolution and current state of landscapes around Lake Teletskoye have not previously been studied in detail. In the valley of the Malye Chily River, which flows into Lake Teletskoye, the timing of dam failure and draining of two morainedammed lakes has been identified. Botanical analysis, ash content determination, and radiocarbon dating of two peat profiles provide insight into postglacial evolution of wetlands related to this landscape. We found clear evidence of the disappearance from the peat of higher vascular species that, today, grows mostly in the plains of Siberia. Correlation of the data obtained with the accepted chronology of the Holocene events in the Russian Altai suggests the following stages of postglacial environmental change in the Malye Chily River valley: (1) the continuation of the Late Wiirm glaciation degradation (before 7000 cal. yr BP); (2) Holocene Climate Optimum (7000-5000 cal. yr BP); (3) Akkem cooling (5000-4200 cal. yr BP); (4) warm period (4200-3700 cal. yr BP); and (5) Historical cooling (3700-1600 cal. yr BP). [ABSTRACT FROM AUTHOR]

The Turgen Mountains lie in northwestern Mongolia, roughly 80 km south of the Russian border. The area was visited in 1910 by a Royal Geographical Society expedition led by Douglas Carruthers. The party undertook an extensive survey of the range and also documented the extent of the glaciers with photographs. One hundred years later, in summer 2010, a US- Mongolian expedition retraced portions of the 1910 expedition. Camera locations were matched to the historical photographs and repeated photographs taken. In addition, the termini of the two main glacial lobes were surveyed by GPS. Analyses of field data, repeated photographs from 1910 and 2010, topographic maps from 1970, and satellite imagery from 1992 and 2010 were used to describe the changes in the glacial system. The results suggest that while the snow and ice volume on the summits appears to be intact, lower elevation glaciers show significant recession and ablation. From 1910 to 2010, West Turgen Glacier receded by c. 600 m and down-wasted by c. 70 m. This study successively demonstrates the utility of using historic expedition documents to extend the modern record of glacial change. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge about the dynamics of modern glaciers is relevant for evaluating climatic change. However, there is very little and conflicting information about the extent of modern glaciers in northwestern Mongolia. Thus, the aim of this paper is to present detailed data about the extent of modern glaciers in the Turgen–Kharkhiraa Mountains in the northwestern part of the Mongolian Altai and to distinguish three main phases of ice extent: in 1991, in 1948, and back to the Holocene glacial epoch including the so-called Little Ice Age (LIA) — a worldwide cooling period beginning in the 16th century and lasting until the end of the 19th century (). Based on field work, topographic maps and aerial photographs of this region, the investigations have shown glacier retreat in 1991, since 1948, as compared to Holocene glaciations including the so-called Little Ice Age period. Using the toe-to-summit altitude (TSAM) method, the overall modern snowline can be calculated at about 3537–3559masl; the area of present glaciers can be calculated to be 33.8km2 for the Turgen Mountains and 39.5km2 for the Kharkhiraa Mountains. This is more than 25% of the glaciated area of Mongolia. The LIA snowline was about ∼80m lower (3461–3480masl), whereby the glaciated areas during the LIA was 76.8km2 and 80.8km2 in the two mountain systems, respectively. In conclusion, there has been a remarkable glacier retreat from this Holocene and Little Ice Age compared to the glaciation in 1948 and 1991. This glacier retreat coincides with an increase in the snowlines. [Copyright &y& Elsevier]

Results of research into climate and glacier dynamics in the Altai Mountains (Russia) over the period of instrumental observations (1952-2008) are presented in this article. About 1030 glaciers with a total area of 805 km and volume of 42.5 km have been recorded in the Altai Region. The average summer air temperature in different regions of the Altai has increased during the study period from about 0.2°C (Aktru) to 1.1°C (Akkem). The annual atmospheric precipitation rate has also increased, by 8-10%. Since 1952, the glacier area in different regions of the Altai has decreased by 9-27%, and volume by 12-24%. By 2008, as a result of degradation, the total number of glaciers was 953 with an area of 724 km and volume of 38 km. [ABSTRACT FROM AUTHOR]

In order to study the chemical characteristics of snow-firn pack in Altai Mountains and its environmental significance, a 1.5-m deep snow-firn pack was dug in the accumulation zone (3 300 m a.s.l.) of the Kanas Glacier in August 2009. A total of 15 samples were analyzed for major ions. Results show that the concentrations of major ions in the snow-firn pack are NH>SO>Ca>NO>Na>Cl>K>Mg. NH is the dominant cation with a medium value of 4.7 ueq·L, accounting for 39.8% of the total cations, and SO is the dominant anion, with a medium value of 4.0 ueq·L, which accounts for 33.9% of the total cations. Compared with Belukha Glacier (Altai), Urumqi Glacier No. 1, and the Inilchek Glacier (Tienshan), there is a lower ion concentrations in the Kanas snow-firn pack. Potential sources of these chemical species are explored using correlation and empirical orthogonal function (EOF) analyses. The analyses indicate that major ion concentrations (except NH) originate from crustal dust. Backward trajectory analysis was applied to get the origin of the air mass to Kanas Glacier. The results suggest that air pollutants emitted by forest fires in Siberia could be transported and influence the NH, NO, and SO concentrations on the Kanas Glacier. [ABSTRACT FROM AUTHOR]

Abstract: The Kanas River originates on the southern slope of Youyi Peak, the largest center of modern glaciers in Altai Mountains, China. Three sets of moraines and associated glacial sediments are well preserved near the Kanas Lake outlet, recording a complex history and landscape evolution during the Last Glacial. Dating the moraines allows the temporal and spatial glacier shift and climate during the Last Glacial to be determined, and then constrains when and how the Kanas Lake basin was formed. Dating of the glacial tills was undertaken by utilizing the optically stimulated luminescence (OSL) method. Results date four samples from the three sets of moraines to 28.0, 34.4, 38.1, and 49.9ka and one sample from outwash sediment to 6.8ka. The Kanas Lake basin is a downfaulted basin and was eroded by glacier before 28.0ka, and the glacial moraines blocked the glacier-melt water after the glacier retreat, which made the present-day Kanas Lake eventually form at least before 6.8ka BP. In Altai Mountains, the glacier advance was more extensive in Marine Isotope Stage (MIS) 3 than MIS 2, probably because the mid-latitude westerlies shifted northward and/or intensified during the MIS 3, resulting in a more positive glacier mass balance. Nevertheless, the Siberian High dominated the Altai Mountains in MIS 2, resulting in a relative decrease in precipitation. [Copyright &y& Elsevier]

The objective of this study is to reveal the isotopic composition of ice and meltwater in glaciated regions of South-Eastern Altai. The paper depicts differences between the isotopic composition of glacier ice from several types of glaciers and from various locations. Detected differences between the isotopic composition of glacier ice in diversified parts of the study region are related to local climate patterns. Isotopic composition of meltwater and isotopic separation for glacier rivers runoff showed that in the Tavan-Bogd massif, seasonal snow participates more in the formation of glacier runoff due to better conditions for snow accumulation on the surface of glaciers. In other research areas pure glacier meltwater prevails in runoff. [ABSTRACT FROM AUTHOR]

The glacier snowline altitude (SLA) at the end of the melt season is an indicator of the glacier equilibrium line altitude and can be used to estimate glacier mass balance and reconstruct past climate. This study analyzes the spatiotemporal variability in glacier SLA across High Mountain Asia, including the Altai Mountains, Karakoram Mountains, Western Himalayas, Gongga Mountains, Tian Shan, and Nyainqentanglha Mountains, over the past 30 years (1989–2019) to better elucidate the state of these mountain glaciers. Remote-sensing data are processed to delineate the glacier SLA across these mountainous regions, and nearby weather station data are incorporated to determine the potential relationships between SLA and temperature/precipitation. The mean SLAs across the Altai and Karakoram mountains ranged from 2860 ± 169 m to 3200 ± 152 m and from 5120 ± 159 m to 5320 ± 240 m, respectively, with both regions experiencing an average increase of up to 137 m over the past 30 years. Furthermore, the mean glacier SLAs across the Western Himalayas and Gongga Mountains increased by 190–282 m over the past 30 years, with both regions experiencing large fluctuations. In particular, the mean glacier SLA across the Western Himalayas varied from 4910 ± 190 m in 1989 to 5380 ± 164 m in 2000, and that across the Gongga Mountains varied from 4960 ± 70 m in 1989 to 5330 ± 100 m in 2012. Correlation analyses between glacier SLA and temperature/precipitation suggest that temperature is the primary factor influencing glacier SLA across these High Mountain Asia glaciers. There is a broad increase in glacier SLA from the Altai Mountains to the Karakoram Mountains, with a decrease in glacier SLA with decreasing latitude across the Himalayas; the maximum SLA occurs near the northern slopes of the Western Himalayas. The glacier SLA is lower on the eastern side of the Tibetan Plateau and exhibits a longitudinal distribution pattern. These results are expected to provide useful information for evaluating the state of High Mountain Asia glaciers, as well as their response and feedback to climate change. [ABSTRACT FROM AUTHOR]

Located in Asia where Russia, China, Mongolia, and Kazakhstan share a border, the Altai Mountains are composed by high ranges peaking at 4,506 m (Belukha), still glaciated large plateaus and deep valleys. With more than 1000 km², the Altai glaciers represent 50 % of the glaciated area of North Asia. Although because of repeated occurrences of glacial megafloods during the Pleistocene have been intensively studied in Russian Altai, the chronology and extent of its glaciations are poorly understood compared to other Central Asian regions.In relation with archaeological researches developed by the Russian-French team ARTEMIR, we investigated the upper Kalguty basin located in the south-eastern part of the Ukok Plateau, Russian Altai. Along the border with Mongolia, the elevation of this very dry area (100 mm/a) ranges from 2300 to 3500 m. Although current glacier area is < 0.25 km², many glacial landforms allow reconstructing past glaciations in the upper Kalguty basin. A detailed geomorphological study was carried out on the field in July 2015, and rock samples were taken on scoured bedrock and erratic boulders at one key site for surface exposure dating using in situ-produced cosmogenic nuclides.The maximal extent of the Kalguty valley glacier in the upper basin occurred shortly before 20.9 ka. As evidenced by moraines and kame terraces located higher on one valley side, larger and earlier, but not dated, glaciations occurred prior to the ~21 ka Kalguty Glacier advance. On the other hand, three morainic complexes testify to smaller advances corresponding to a reduced Kalguty glacier and two smaller valley glaciers. Reconstructed ELAs of these former glaciers were used to infer their Late Glacial extents ages and the corresponding regional palaeoclimatic conditions. The results regarding the chronology and extent of the Kalguty Basin glaciations since the LGM are discussed by relating them to other regional studies in the Altai Mountains and Central Asia. [ABSTRACT FROM AUTHOR]

The Tavan Bogd mountains (of which, the main peak, Khuiten Uul, reaches 4374 m a.s.l.) are situated in the central part of the Altai mountain system, in the territories of Russia, Mongolia and China. The massif is the largest glacierized area of Altai. The purposes of this study were to provide a full description of the scale and structure of the modern glacierized area of the Tavan Bogd massif, to reconstruct the glaciers of the Little Ice Age (LIA), to estimate the extent of the glaciers in 1968, and to determine the main glacial trends, and their causes, from the peak of the LIA. This work was based on the results of long-term field studies and analysis of satellite and aerial data. At the peak of the LIA, Tavan Bogd glaciation comprised 243 glaciers with a total area of 353.4 km2. From interpretation of Corona images, by 1968 the number of glaciers had decreased to 236, with a total area of 242 km2. In 2010, there were 225 glaciers with a total area of 201 km2. Thus, since the peak of the LIA, the glacierized area of the Tavan Bogd mountains decreased by 43%, which is somewhat less than for neighboring glacial centers (i.e., Ikh-Turgen, Tsambagarav, Tsengel-Khairkhan and Mongun-Taiga mountains). The probable causes are higher altitude and the predominance of larger glaciers resistant to warming. Accordingly, the smallest decline in Tavan Bogd occurred in the basins of the Tsagan-Gol (31.7%) and Sangadyr (36.4%) rivers where the largest glaciers are located. In contrast, on the lower periphery of the massif, where small glaciers predominate, the relative reduction was large (74–79%). In terms of general retreat trends, large valley glaciers retreated faster in 1968–1977 and after 2010. During the 1990s, the retreat was slow. After 2010, glacial retreat was rapid. The retreat of glaciers in the last 50–60 years was caused by a trend decrease in precipitation until the mid-1970s, and a sharp warming in the 1990s and early 2000s. [ABSTRACT FROM AUTHOR]

Pollen taxa in sediment samples can be identified based on morphology. However, closely related species do not differ substantially in pollen morphology, and accurate identification is generally limited to genera or families. Because many pollen grains in glaciers contain protoplasm, genetic information obtained from pollen grains should enable the identification of plant taxa at the species level. In the present study, species identification of Pinus pollen grains was attempted using whole-genome amplification (WGA). We used pollen grains extracted from surface snow (depth, 1.8–1.9 m) from the Belukha glacier in the summer of 2003. WGA was performed using a single pollen grain. Some regions of the chloroplast genome were amplified by PCR, and the DNA products were sequenced to identify the pollen grain. Pinus includes approximately 111 recognized species in two subgenera, four sections, and 11 subsections. The tree species Pinus sibirica and P. sylvestris are currently found at the periphery of the glacier. We identified the pollen grains from the Belukha glacier to the level of section or subsection to which P. sibirica and P. sylvestris belong. Moreover, we specifically identified two pollen grains as P. sibirica or P. cembra. Fifteen species, including P. sibirica, were candidates for the remaining pollen grain. [ABSTRACT FROM AUTHOR]