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ABSTRACT In an era of rapid environmental change, accurately modeling aquatic ecosystems, particularly the lateral water flow through soil and permafrost, remains a pressing need. This study addresses this through the Water and Energy Transfer Process (WEP) model. The WEP model overcomes the limitations of previous models and plays a crucial role in estimating the lateral flow of groundwater in the basin. In this study, we use our new formula for calculating the lateral flow at the permafrost depth and the deep percolation formula to study the subsurface, over permafrost, and lateral water flows in the cold permafrost for 52 years (1970–2021). The model’s application in Mongolia’s Great Lakes basin, specifically the Khovd River-Khar-Us Lake basin, achieved Nash–Sutcliffe model efficiency (NSE) coefficients of 0.64–0.75. This suggests that the model is plausible and suitable for further research. Additionally, the model effectively captured soil temperature dynamics, with NSE coefficients ranging from 0.95 to 0.98 in the upper soil layer to 0.35–0.80 at a depth of 100 cm. These findings validate the model’s ability to accurately account for lateral water flow above the permafrost layer in cold regions. Future work will extend these calculations to different conditions and basins.

The Altai Mountains contain rivers, lakes, and glaciers critical for the survival of both social and ecological systems. Reconstructing past hydroclimatic changes is crucial for understanding human-environment interactions and predicting future hydroclimatic dynamics in this region. We reconstructed the water level fluctuations of Tolbo Lake in the Altai Mountains over the past 13.7 kyr using the sedimentary cladoceran fossils. The results show that a rising trend of the Holocene lake level resulted mainly from intensification of westerlies-driven precipitation. The results further reveal that the centennial timescale lake-level fluctuations during the mid–late Holocene was mainly modified by temperature-controlled meltwater input, resulting in low lake levels during the cold, glacier-advance periods and high lake levels during the warm, glacier-retreat periods. The intensification of westerlies-driven precipitation at ∼6 cal ka …

This study investigates the glacial lake outburst flood (GLOF) hazards in the Tsambagarav mountain range in Western Mongolia, focusing on the Khukhnuruu Valley and its interconnected proglacial lakes. Over the last 30 years, significant glacier retreats, driven by rising temperatures and changing precipitation patterns, have led to the formation and expansion of several proglacial lakes. Fieldwork combined with satellite data and meteorological analysis was used to assess the dynamics of glacier and lake area changes, with particular focus on the flood events of July 2021. The research reveals a substantial reduction in glacier area, particularly in the Khukhnuruu E complex, where glacier area decreased by 19.3%. The study highlights the influence of increasing temperatures and summer precipitation, which have accelerated ice melt, contributing to the expansion and eventual breaching of lakes. Additionally, lake area changes were influenced by the steepness of the terrain, with steeper slopes exacerbating peak discharge during floods. Of the studied seven lakes (Lake 1 to Lake 7), Lake 1 experienced the most dramatic reduction, with a decrease in area by 73.51% and volume by 84.84%, followed by Lake 7. This study underscores the region’s vulnerability to climate-induced hazards and stresses the need for a comprehensive early warning system and disaster preparedness measures to mitigate future risks.

This study investigates the glacial lake outburst flood (GLOF) hazards in the Tsambagarav mountain range in Western Mongolia, focusing on the Khukhnuruu Valley and its interconnected proglacial lakes. Over the last 30 years, significant glacier retreats, driven by rising temperatures and changing precipitation patterns, have led to the formation and expansion of several proglacial lakes. Fieldwork combined with satellite data and meteorological analysis was used to assess the dynamics of glacier and lake area changes, with particular focus on the flood events of July 2021. The research reveals a substantial reduction in glacier area, particularly in the Khukhnuruu E complex, where glacier area decreased by 19.3%. The study highlights the influence of increasing temperatures and summer precipitation, which have accelerated ice melt, contributing to the expansion and eventual breaching of lakes. Additionally, lake area changes were influenced by the steepness of the terrain, with steeper slopes exacerbating peak discharge during floods. Of the studied seven lakes (Lake 1 to Lake 7), Lake 1 experienced the most dramatic reduction, with a decrease in area by 73.51% and volume by 84.84%, followed by Lake 7. This study underscores the region’s vulnerability to climate-induced hazards and stresses the need for a comprehensive early warning system and disaster preparedness measures to mitigate future risks

The High Mountains of Asia, often called the “Third Pole” because they constitute the third largest reserve of water after the North and South Poles, are an important landscape worldwide. Western Mongolia forms part of the northeastern extent of the Third Pole, characterized by high mountain ranges and river catchment areas. The ecosystems in these high mountains, including the nomads that inhabit them, are fragile and vulnerable to environmental changes. In this study, we conducted household interviews with nomads in the Tsambagarav (TsGM) and the Munkhkhairkhan (MKhM) Mountains and, used a sustainable livelihood approach to assess the livelihood vulnerability index (LVI) of the nomads. The results showed that the overall LVI was 0.41 for TsGM and 0.44 for MKhM, with corresponding Intergovernmental Panel on Climate Change-LVI of 0.01 for TsGM and − 0.02 for MKhM. Based on the findings, we recommend that decision-makers should focus on several key areas: effectively managing pasture land; implementing policies for sustainable yields; establishing an insurance-based compensation system, post-disaster communication system; and a mobile-economy informative early warning system; and lowering the loan interest rate. Among recommendations, developing a mobile-economy informative early warning system is an innovative idea to mitigate climate change disasters. These actions can contribute to a long-term sustainable livelihood in the fast-changing climate.

The western region of Mongolia is characterized by an arid climate and a fragile ecological environment. It is a sensitive zone in response to global climate change and one of the major sources of dust globally. This region is home to numerous lakes, and their dynamic changes not only reflect global climate variations but also have implications for the global ecological environment quality. In this study, Landsat images were used as the data source, and Google Earth Engine (GEE) was employed to extract lakes with an area larger than 1 km2 from 1992 to 2021. The spatiotemporal characteristics of lake water area (LWA) changes were analyzed, and a structural equation model was applied to attribute the lake changes. The results indicate an overall trend of increasing lake area followed by a decrease in the study area. Specifically, lakes in the provinces of Khovd and Gobi-Altai exhibited a decreasing trend followed by an increasing trend, while lakes in the provinces of Uvs and Zavkhan showed an increasing trend followed by a decreasing trend. Three typical types of lakes, namely, alpine lakes, throughflow lakes, and terminal lakes, all exhibited a trend of increasing area followed by a decrease. The analysis of driving forces behind lake area changes reveals that climate change and human activities primarily exert indirect influences on the lake area changes in each province. Specifically, climate change and human activities lead to changes in soil moisture, which have a significant explanatory power for lake area changes. Regarding the typical types of lakes, climate change serves as the primary driving force for alpine lakes, while human activities are the main driving forces for throughflow lakes and terminal lakes

The scarcity of Holocene winter temperature records from the core area of the Mongolian-Siberian High (MSH) hampers our understanding of the long-term evolution of the MSH and its modulation of the East Asian Winter Monsoon (EAWM). Here we use the body size of Pediastrum, a new and sensitive temperature proxy, from the sediments of Tolbo Lake in the western Mongolian Plateau, to reconstruct changes in winter temperature in the core area of the MSH during the Holocene. A large-scale investigation of modern Pediastrum body size across East Asia indicates that it is an accurate proxy indicator for mean winter temperature. The Holocene winter temperature based on Pediastrum body size from Tolbo Lake shows a general warming trend with the maximum at ∼2.6 ka. The current warming has attained the magnitude of the previous Holocene maximum, despite the underlying forcing being different. The mid-late Holocene winter warming in inland Eurasia may have weakened the MSH and reduced the intensity of the EAWM.

Holocene climate changes in the Altai Mountains and the surrounding areas are well documented, but the timing of the Holocene precipitation maximum remains controversial. We obtained 17 accelerator mass spectrometry (AMS) 14C dates and 310 fossil pollen assemblages from sediments in Tolbo Lake, which we used to reconstruct the history of vegetation and climate change in the Mongolian Altai Mountains over the past 13,750 years. The results suggest that mean annual precipitation (Pann) was the most significant control on the fossil pollen record at the study site. Based on the fossil pollen record from Tolbo Lake and 469 surface pollen samples within the radius of 1300 km, the reconstructed Pann was lowest during 13.7–11.3 ka (1 ka = 1,000 cal yr BP); relatively low but increasing Pann occurred in the early Holocene (11.3–9.4 ka); and maximum Pann occurred during the middle to late Holocene (after 6.8 ka), possibly because of the high temperatures. A significant climatic and ecological transition occurred in the Altai Mountains at ∼7 ka: steppe and desert steppe vegetation with generally low Pann was present before ∼7 ka, while subsequently there was the expansion of forest vegetation and a marked increase in Pann, possibly in response to the minimum in Northern Hemisphere ice sheets and the increased radiative forcing caused by rising atmospheric greenhouse gases.

Global climatic changes in recent decades cause changes in the dynamics of mountain geosystems. Of interest is the response of nival-glacial inland geosystems, which is different from those in the pre-Oceanic regions. In 2013, the authors substantiated the expediency of separating the nival-glacial mountain range geosystems within the Baikal Rift Zone and Mongolian Altai into a meridional research transect, within which it is possible to establish latitudinal patterns of modern intracontinental glacier functioning. Over the past decade of ongoing studies of glacial forms within the transect, many new data have been collected and analyzed. The present article based on systematic generalizations of these materials. The analysis of the state of mountain glaciation in the south of Eastern Siberia and Mongolia in the last decades has revealed a number of peculiarities. The deglaciation that began in the 1970s–1980s continues in all the mountain systems under consideration. It is a reaction to global climatic changes. The greatest reduction is experienced by the near-slope glaciers and flattop glaciers and to a lesser extent by the cirque ice glaciers. They have a significant volume loss due to thinning, while changes in the area of such glaciers are less significant. This is the main difference between the intracontinental glaciers and the preoceanic glaciers. In general, many nival-glacial geosystems of transitional forms are formed. Quantitative characteristics are based on the calculation of the volume of the East Sayan glaciers measured by geophysical radar. Thus, over 120 years, the Peretolchina (northern) Glacier has decreased in length by a factor of 1.75, in area by a factor of 2.9, and in volume by a factor of 3.71. During the same period, the area of the neighboring Radde Glacier decreased from 0.43 to 0.09 km2; its thickness by 30 m; and, accordingly, its volume by 3 times. The warming of air temperature for Western Mongolia is 0.03–0.29°C/10 years and, for the Baikal region, 0.2–0.5°C/10 years. Warming of air temperatures in the ridges of the Mongolian Altai is noted up to 48° N, and southward the trend is unstable.

Abstract—Global climatic changes in recent decades cause changes in the dynamics of mountain geosystems. Of interest is the response of nival-glacial inland geosystems, which is different from those in the pre-Oceanic regions. In 2013, the authors substantiated the expediency of separating the nival-glacial mountain range geosystems within the Baikal Rift Zone and Mongolian Altai into a meridional research transect, within which it is possible to establish latitudinal patterns of modern intracontinental glacier functioning. Over the past decade of ongoing studies of glacial forms within the transect, many new data have been collected and analyzed. The present article based on systematic generalizations of these materials. The analysis of the state of mountain glaciation in the south of Eastern Siberia and Mongolia in the last decades has revealed a number of peculiarities. The deglaciation that began in the 1970s–1980s continues in all the mountain systems under consideration. It is a reaction to global climatic changes. The greatest reduction is experienced by the near-slope glaciers and flattop glaciers and to a lesser extent by the cirque ice glaciers. They have a significant volume loss due to thinning, while changes in the area of such glaciers are less significant. This is the main difference between the intracontinental glaciers and the preoceanic glaciers. In general, many nival-glacial geosystems of transitional forms are formed. Quantitative characteristics are based on the calculation of the volume of the East Sayan glaciers measured by geophysical radar. Thus, over 120 years, the Peretolchina (northern) Glacier has decreased in length by a factor of 1.75, in area by a factor of 2.9, and in volume by a factor of 3.71. During the same period, the area of the neighboring Radde Glacier decreased from 0.43 to 0.09 km2; its thickness by 30 m; and, accordingly, its volume by 3 times. The warming of air temperature for Western Mongolia is 0.03–0.29°C/10 years and, for the Baikal region, 0.2–0.5°C/10 years. Warming of air temperatures in the ridges of the Mongolian Altai is noted up to 48° N, and southward the trend is unstable.

Abstract: 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.

Сибирийн болон хил залгаа бүс нутгийн хүрээлэн буй орчны өөрчлөлт, Алтай-Соёны бүс нутагт хэрхэн нөлөөлөх талаар. Монгол Алтайн нурууны мөсөн голын хайлалт сүүлийн 40 жилд дунджаар 33%, мөстөлийн гаралтай нуурын задрал зэрэг гамшигт үзэгдэл гарах болсон үүнтэй холбоотой экологи, хүн ам, иргэдэд хэрхэн сөрөг нөлөөлөл үзүүлэх, үүнийг бууруулах тал дээр бүс нутгийн судалгаа, хамтын ажиллагааны боломж

An in-depth analysis of temporal changes in hydrothermal regimes of natural seasons has been performed for the period from 1936 to 2016 to identify the reasons behind the activation of cryogenic landslide processes in the Southeastern Altai Mountains. Ultra-high-resolution satellite imagery is used to identify the years of peak landslide activity; the climatic parameters registered in these years are compared with those computed for the period preceding the beginning of steady global climate change (1936–1970). The analysis results indicate a pronounced climate warming and its active impact on high-mountain cryogenic systems. Landslide intensification periods caused by extreme thawing in the active cryolithozone layer in 1998, 2012, and 2016 statistically significantly correlate with anomalous values of parameters characterizing hydrothermal regimes of natural seasons and their structural units.

ХураангуйДэлхийн дулаарлын нөлөөгөөркериосферт ихээхэн өөрчлөлтүүд илэрчбайгаагийн нэг жишээ ньмөстөл, мөсөн голын хайлалтын үйл явцюм. Мөс нь цэвэр усны нөөцийг агуулж экосистемийн тэнцвэрт байдлыг хадгалахын зэрэгцээ уур амьсгалын өөрчлөлтийн гол илтгэгч болдог онцлогтой. Ялангуяа хуурай, хагас хуурай бүсийн өндөрлөг уулсын бүсэдорших мөстлийн өөрчлөлтнь экосистем болон байгаль орчиндасар их нөлөөтэйбайдаг. Энэ судалгаагаар Монгол Алтайн нуруунымөстлийн томоохон цогцолборын нэг болох Цамбагарав уулын орчин үеийн мөстөл, түүний талбайн өөрчлөлт, хайлалтад нөлөөлөх хүчин зүйл,түүнийүр дагаврыг Зайнаас тандан судлалын аргазүй, Чиг хандлагын шинжилгээ (MK), статистикшинжилгээнийаргуудаартодорхойлсон. Цамбагарав ууланд 2022 оны байдлаар 59.7 км² мөстөл бүхий талбайны90 гаруй хувь нь 3500 метрээс дээш өндөрт төвлөрч байна. 1969-2022 оны хооронд буюу сүүлийн 53 жилд нийт талбай нь 42.4 %-ар алдралд оржээ. MK шинжилгээгээр зүг зовхисын хувьдагаарын температур хойд (Z=2.54), зүүн хойд (Z=2.31) зүгүүдэд агаарын температур хамгийн их нэмэгдсэн болхур тунадас хойд (Z=-0.29), зүүн хойд (Z=-0.98) буурч бусад Цамбагарав уулыг зүгүүдэд өсжээ. Тодруулбал 2012 оноос эхлэн агаарын температур нэмэгдэхийн зэрэгцээ хур тунадас аажим өсөх хандлага ажиглагдав. Хойд хэсгийн Нурган нуурын талбай тогтмол өсөх хандлагатай бол, Өмнө хэсгийн Ногоон нуурын талбай 1969-1990 онхүртэл буурч, түүнээс хойших хугацаандөсөх хандлагаилэрсэн. Мөстөл хайлж, мөсөн голуудын талбайн хэмжээ багасахын хэрээр нууруудын талбай нэмэгдэх хандлагань хоорондоо шууд хамааралтай байв. Гэвч цаашид энэ уулсаасэх авах голуудын урсац нэмэгдэх, нуурын усны эзлэхүүннь нэмэгдэжмөстлийнгаралтай жижиг нууруудын задралын үер үүсэхзэрэгуур амьсгалын өөрчлөлтөөс үүдсэн байгалийн гамшигт үзэгдлүүднэмэгдэх эрсдэлнэмэгдэж байна.Түлхүүр үгс: Зүг зовхис,Уур амьсгалын өөрчлөлт, Нуурын талбайн өөрчлөлт, Гадаргын хэвгий, Хур тунадас, Агаарын температурAbstractOne of the major changes in the cryosphere due to warming is the melting of ice sheets and glaciers. Ice contains freshwater resources, maintains the ecosystem's balance, and is a key indicator of climate change. In particular, changes in glaciation in the highlands of arid and semi-arid regions significantly impact ecosystems and livelihoods. Therefore, in this study, the modern glacier of Mount Tsambagarav, one of the majorglaciation complexes of the Mongolian Altai Mountains, and the factors and consequences affecting its area change and melting were determined using remote sensing, trend analysis, and statistical methods. As of 2022, Tsambagarav Mountain has 59.7 km² of ice, more than 90 percent concentrated at an altitude of more than 3500 meters. Between 1969 and 2022, or in the last 53 years, the total area has increased by 42.4%. According to MK analysis, air temperature increased the most in the north (Z=2.54) and northeast (Z=2.31) regions. At the same time, precipitation decreased in the north (Z=-0.29) and northeast (Z=-0.98) and increased in other regions of Tsambagarav mountain. In general, starting in 2012, there has been a tendency to increase precipitation and gradually increase air temperature. While the area of Nurgani Lake in the northern part is constantly increasing, the area of Green Lake in the southern part decreased in 1969-1990, but it is showing a tendency to increase again. As the ice melts and the area of glaciers decreases, the area of lakes increases. However, it also increases the risk of catastrophic phenomena caused by climate change, such as the increase in the flow of source rivers and the increase in the volume of lake water, which will causethe collapse of small lakes of glacial origin. Keywords: Exposition,Climate change, Lake area change, Slope, Precipitation, Air temperature

The history and driving forces of aeolian activity in western Mongolia remain poorly understood due to the scarcity of geological archives. Here, we obtained a record of sediment grain size from Tolbo Lake in western Mongolia to reconstruct changes in aeolian activity since ∼14 ka. The results suggest that intensified aeolian activity in the late Holocene may mainly have been a response to stronger surface winds resulting from an increase in spring insolation and mountain snow. The stable weak aeolian activity appears to coincide with ice-rafting events in the North Atlantic during the middle Holocene and may be a response to warming at northern high latitudes, increased humidity and vegetation coverage in western Mongolia, indicating that dust from western Mongolia would possibly contribute minimally to dust deposition in Greenland during this period. This study will help understand the atmospheric dust emissions and transport processes in the earth system.

An in-depth analysis of temporal changes in hydrothermal regimes of natural seasons has been performed for the period from 1936 to 2016 to identify the reasons behind the activation of cryogenic landslide processes in the Southeastern Altai Mountains. Ultra-high-resolution satellite imagery is used to identify the years of peak landslide activity; the climatic parameters registered in these years are compared with those computed for the period preceding the beginning of steady global climate change (1936–1970). The analysis results indicate a pronounced climate warming and its active impact on high-mountain cryogenic systems. Landslide intensification periods caused by extreme thawing in the active cryolithozone layer in 1998, 2012, and 2016 statistically significantly correlate with anomalous values of parameters characterizing hydrothermal regimes of natural seasons and their structural units.

Strong earthquakes could serve as a trigger for glacier detachment and associated ice–rock avalanches. The 1988 Tsambagarav earthquake (M = 6.4) initiated collapse of part of the glacier tongue and a further ice–rock avalanche with an abnormal 5 km long path in Zuslan valley, Tsambagarav ridge (Mongolian Altai). Early documentation of surface effects in 1988, remote sensing and field data gathered 16 and 30 years after this event allowed for the assessment of the seismic impact on a reduction of “damaged” glacier under conditions of global warming as well as estimating topography changes in this arid and seismically active area. Because of the earthquake, the glacier immediately lost 10.4 % of its area (0.1 km2 of tongue surface). Additionally, 56% of its area was lost during 1988–2015, shrinking much faster than neighboring glaciers of similar size and exposition. Collapse of snow–ice cornice in the accumulation zone could play a key role in rapid acceleration of the detached ice block and abnormally long path of the ice–rock avalanche. A large amount of debris material provided more than 16 years of ice melting. Downstream, the valley avalanche debris cover repeats the topogr

В Монгольском Алтае, как в других горных районах мира, наблюдается множество процессов, индуцированных изменением климата. Одним из таких процессов является “прорыв ледникового озера” (ПЛО). В работе, на основе данных дистанционного зондирования, дана краткая информация о наблюдаемом ПЛО, который произошел 27 июня 2021 года в горном узле Цамбагарав в бассейне р. Битуу-эргийн гол. In the Mongolian Altai, as in other mountainous regions of the world, there are many impacts associated with climate change, one of them is the “glacial lake outburst” (GLO). In the work, based on the remote sensing method, brief information is considered about the GLO phenomenon, which took place on June 27, 2021, in the Tsambagarav mountain cluster in the basin of the river Bituu-Ergiin gol.

На основе геоинформационного анализа и наземных экспедиционных исследований в эталонных горно-ледниковых бассейнах Русского и Монгольского Алтая выведен алгоритм расчета внутриструктурного перераспределения водозапасов из гляциальных (в водном эквиваленте) в лимнические системы для заданного временного интервала. Ключевые слова: оледенение, ГИС, водные ресурсы, озера Based on GIS analysis and ground-based expeditionary studies in the reference mountain-glacial basins of the Russian and Mongolian Altai, an algorithm for calculating intrastructural redistribution of water storage from glacial (in water equivalent) to limnic systems for a given time interval was derived. Keywords: glaciation, GIS, water resources, lakes

Although the pattern of Holocene temperature variations in central Asia is complex, it is clear that temperature played a fundamental role in influencing humidity conditions and regional human activity. We reconstructed temperature changes using Pediastrum species data, verified by clumped isotopes (Δ47), in the carbonates of sediment cores recovered from Bosten Lake in Xinjiang Province, northwestern China. Combined with archaeological data, the results indicate an unusually warm climatic interval that peaked at ∼4.7–4.3 kyr and promoted human occupation of the Altai Mountains. The climate cooled during 4.2–4.1 kyr and 3.6–3.5 kyr, as indicated by the decrease or absence of Pediastrum simplex. These cold events may have triggered the southward human migration out of the Altai region, resulting in the widespread distribution of archaeological sites at lower latitudes, in the Tienshan Mountains, and in the desert-oasis areas of the Tarim Basin in southern Xinjiang. Our data support the notion that a series of cultural transitions across the monsoonal Loess Plateau and Tibetan Plateau of China may have been linked to temperature changes during the middle to late Holocene.

The paper is focused on changes in biodiversity, the environment, and human activity in the Uvs Nuur Basin during the last three millennia based on biological and geochemical proxies from the lake Bayan Nuur. Regions with high biodiversity and relatively low anthropogenic pressures are typically the most vulnerable to both climate change and human activities. One such area is the Uvs Nuur Basin located on the north of the Great Lake Depression of Mongolia. The main objective of this study is to assess changes in the past biodiversity of the lake’s microflora and microfauna, and surrounding vegetation biodiversity in the Uvs Nuur Basin, and to determine the main drivers of diversity change. Based on the analysis of pollen and chironomids we conclude that the most humid and afforested phase was between 1400 and 1800 CE. We assume that the Little Ice Age in the Uvs Nuur Basin was humid with mean annual precipitation ca. 305 mm/year and mean July temperature about 13°C. Conversely, the warmest and most arid period was between 650 and 1350 CE with mean annual precipitation ca. 280 mm/year and mean July temperature of about 16°C, attributed to the Medieval Warm Period. The biodiversity of terrestrial plants, chironomids, and Cladocera positive react to changes in annual precipitation and July temperature, whereas diatoms do not correlate directly to the climatic factors. The diversity and the evenness of plants are strongly correlated with the change in the leading biomes. The calculated species turnover suggests no significant changes in plant and Cladocera taxa composition, but significant changes in diatom and chironomid communities. This may be explained by the instability of lake ecology due to the fluctuation of the salinity and acidity of the water. An additional aim was to assess if dung fungi in lacustrine sediments reflect changes in human population density around the lake. We found that neither historical sources of human presence nor the influx of coprophilous fungi are correlated with the inferred climate changes. Coprophilous fungi can be used as individual or additional sources of assessment for the peopling and human-related herbivore density including overgrazing of the studied area.

Цамбагарав ууланд болсон газар хөдлөлийн нөлөө, мөсөн голын динамикт хэрхэн нөлөөлсөн

Glacier monitoring tracks progress in limiting climate change - Zurich Open Repository and Archive Header Quicknavigation Home Navigation Content Contact Search Navigation Toggle navigation University of Zurich ZORA University of Zurich ZORA Homepage About ZORA OA-Team Statistics Login DE EN ZORA DE EN oa@ub.uzh.ch Contact Open Access Team via Email Browse by: Year Creators & Editors Communities & Collections DDC Scopus Subject Areas Statistics DE EN Advanced Search Help UZH-Logo Maintenance Infos Glacier monitoring tracks progress in limiting climate change Zemp, Michael (2019).

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.

Characteristics of glacierization of the Tsambagarav mountain ridge were determined on the basis of images obtained from satellites Corona, Landsat-5, Spot-4, Landsat-8 together with results of field investigations. Inventories of glaciers located on the ridge had been prepared for three time periods: 1968, 2006, and 2015. Glacierization of the ridge during the Little Ice Age (LIA) maximum was then reconstructed. In 2015, 67 glaciers formed the ridge glacierization with their total area 68.41 km(2). Mean weighed altitude of the firn line averaged 3748 m. The flat-top glaciers accounted for almost 40% of the glacierization area, and the glaciers composed 6 complexes. For the period of the LIA maximum, 73 glaciers had been reconstructed, their total area was 128.4 km(2), and the calculated firn line altitude -3583.;

Characteristics of glacierization of the Tsambagarav mountain ridge were determined on the basis of images obtained from satellites Corona, Landsat‑5, Spot‑4, Landsat‑8 together with results of field investigations. Inventories of glaciers located on the ridge had been prepared for three time periods: 1968, 2006, and 2015. Glacierization of the ridge during the Little Ice Age (LIA) maximum was then reconstructed. In 2015, 67 glaciers formed the ridge glacierization with their total area 68.41 km2. Mean weighed altitude of the firn line averaged 3748 m. The flat‑top glaciers accounted for almost 40% of the glacierization area, and the glaciers composed 6 complexes. For the period of the LIA maximum, 73 glaciers had been reconstructed, their total area was 128.4 km2, and the calculated firn line altitude–3583 м; these glaciers were combined into two complexes where the flat‑top glaciers predominated as well. By 1968, the area of the glacierization decreased by 36%, and the firn line altitude increased by 89 m. By 2006, area of glaciers decreased down to 71.32 km2, and the firn line altitude increased more by 60 m. Finally, in 2006–2015, area of the glacierization contracted additionally by 2.91 km2, and the firn line altitude still more increased by 16 m. Over the whole period from the LIA maximum, the flat‑top glaciers reduced the most. The general rate of contraction of glaciers tends to increase. Reconstructed rates of retreating of the valley glaciers of the Tsambagarav ridge are similar to estimates of other researchers made for the nearest centers of glacierization.

Arid and semi-arid regions are the first to be affected by hydro-climatic changes. The Great Lakes Depression Basin in western Mongolia is the most notable example of such a region. Therefore, analyzing hydro-climatic changes in the Great Lakes Depression region is essential for future climate, hydrological, eco-hydrological processes, and ecosystem studies in similar areas and basins. In this study, Mann–Kendall (MK), innovative trend analysis method (ITAM), and Sen's slope estimator test (SSET) were used to determine the interrelationship between climate and river discharge changes and lake water level changes through statistical analysis. During the last 30 years, the air temperature has increased by 1.2 °C (Z = 1.16). Total annual precipitation decreased by 23.44 mm, resulting in 134.16 mm (Z = −0.79). The river discharge of the major rivers, such as Khovd River (Z = −3.51) and Zavkhan River (Z = −6.01), has significantly decreased. In Uvs (Z = 0.30) and Khyargas (Z = 2.03) lakes, the water level has also dropped. This study confirms that the increase in air temperature in the depression area of the Great Lakes reduces the amount of precipitation, and the decrease in precipitation affects the decrease in river discharge, which further affects the water level of the inflowing lakes.