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The aim of this paper was to determine the effect of the beta3-adrenergic receptor agonist mirabegron on the free-radical activity of venous blood neutrophils in non-pregnant women. Materials and methods. Using the chemiluminescent method (BChL-07 biochemiluminometer), the parameters of the radical response of venous blood neutrophils in 40 non-pregnant women were determined in different phases of the cycle and on the first day after childbirth with additional cell stimulation with latex particles (0.08 μm). When the noise level was automatically subtracted, the following were recorded: maximum intensity of the synthesis of reactive oxygen species, time to reach the maximum of synthesis intensity, and area under the chemiluminogram curve, reflecting the total synthesis of radical particles over the course of 30 min. These parameters were determined before and after an in vitro introduction of the beta -adrenergic receptor agonist mirabegron (10–6 g/l), beta-adrenergic receptor blocker propranolol hydrochloride (10–6 g/l) and agonist against the background of the blocker into the venous blood. Results. Using the Wilcoxon signed-rank test, we showed an increase in the free-radical activity of neutrophils in women in the follicular phase of the menstrual cycle under the influence of mirabegron for all three evaluated parameters. In the luteal phase, mirabegron significantly increased the rate of reaction development and the total synthesis of radical particles, but did not affect the intensity of production of activated oxygen species. However, no effect was observed on the first day after delivery. The possible mechanism of the revealed mirabegron action is discussed in the article. The authors believe that changes in the activity of venous blood neutrophils under the action of mirabegron may be due to changes in the quantity or sensitivity of beta3-adrenergic receptors in different phases of reproduction.

This paper presents new multi-proxy records of the Holocene environmental and climatic changes in the Western Caucasus revealed from a continuous sediment sequence from mountainous Lake Khuko (Caucasus State Natural Biospheric Reserve, 1744 m a.s.l.). Palaeoecological analyses of a sediment core for grain size, magnetic susceptibility, loss on ignition, and pollen allowed us to determine five principal climatic phases with several subphases since 10.5 ka BP. The age model is based on seven accelerator mass spectrometry 14C dates, supplemented by 210Pb data for the uppermost part of the sediment core. Warm periods (10.5–6.7, 6.7–5.5, 3.5–2.4, 0.8–0.5 ka BP) were characterized by high biological productivity in the lake as indicated by high organic matter content and expansion of forests, typical of modern low and middle mountain zones, as indicated by the increase in abundance of Quercus, Ulmus, Corylus, and Tilia in the pollen assemblages. Cold periods (5.5–3.5, 2.4–0.8, and 0.5 ka BP–present) are marked by a consistent decrease in organic matter content in lake deposits and possibly higher intensity of the catchment erosion. The changes in pollen assemblages (for instance peaks of Abies, Picea, and Pinus) suggested a potential elevational decline in the boundaries of vegetation belts and expansion of high-altitude woodlands. Abrupt changes in the lake ecosystem were identified between 4.2 and 3.5 ka cal BP marked by a short-term variation in sediment regime shown by variation in organic matter content, magnetic susceptibility values, and sediment grain size. This was probably caused by climatic fluctuations in the Western Caucasus region as a result of complex shifts in the ocean-atmosphere system during the 4.2 ka event. Overall, the first Holocene multi-proxy continuous lake sediment record provides new insights into the climate history in the Western Caucasus.

Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmental change. Publisher PDF

We present the European Russia Drought Atlas (ERDA) that covers the East European Plain to the Ural Mountains from 1400–2016 CE. Like the Old World Drought Atlas (OWDA) for the Euro-Mediterranean region, the ERDA is a one-half degree gridded reconstruction of summer Palmer Drought Severity Indices estimated from a network of annual tree-ring chronologies. Ensemble point-by-point regression is used to generate the ERDA with the identical protocols used for developing the OWDA. Split calibration/validation tests of the ERDA indicate that it has significant skill over most of its domain and is much more skillful than the OWDA where they overlap in the western part of ERDA domain. Comparisons to historical droughts over European Russia additionally support the ERDA’s overall validity. The ERDA has been spatially smoothed and infilled using a local regression method to yield a spatially complete drought atlas back to 1400 CE. EOF analysis indicates that there are three principal modes of hydroclimatic variability in the ERDA. After Varimax rotation, these modes correlate significantly with independent climate data sets extending back to the late nineteenth century in a physically interpretable way and relate to atmospheric circulation dynamics of droughts and heatwaves over European Russia based on more recent instrumental data.

The paper presents the results of an analysis of the spatial variability of pine tree-ring growth in the Solovetsky Islands. As a result of the field work, tree-ring network containing 14 dendrochronological pine sites in various habitats were developed. For each site, a local tree-ring width pine chronology (from 472 to 271 years) is obtained, representing pine growth features in different habitat conditions. A comparison between chronologies revealed synchronious growth of pine in various habitats in the late 17th, in the first half of the 18th and the beginning of the 19th centuries. The use of cluster analysis allowed to identify several groups of chronologies with similar characteristics. So, trees growing on swamps, on a sandy substrate and in a green-moss pine forest or in a mixed forest are allocated in separate clusters. This clustering is also confirmed by the results of a dendroclimatic analysis of local chronologies. It turned out that the increase in the pine’s growth in the mixed forest and in the green-moss pine forest depends on the July air temperature variation. Inside this group, samples from pine forests have a common feature – a positive relationship of growth with the precipitation of September. The only site located on the sands showed a different climatic signal than the other chronologies, namely, the dependence on the temperature of August.

Cores of bottom sediments of Lake Karakel (Northern Caucasus) were obtained in 2010 and 2014 to perform geochemical studies for reconstructing the regional paleoclimate of the late Holocene. Solid samples of bottom sediments were scanned via micro-XRF with a step of 1 mm at the shared resource center of the Siberian Synchrotron and Terahertz Radiation Center. The contents of more than 20 elements were determined. The scan profiles are used to construct a single reference section with correction for a sediment layer dated via radiocarbon analysis, and to create a sediment core age–depth model.

The age of moraines of the Greater Azau Glacier was identified by tree-ring analysis of more than 150 Scots pines, by historical and cartographic data, remote sensing, lichenometric and radiocarbon dating. We determined the limits of the area covered by the glacier tongue at the end of the 19th century. We also discuss the controversial issue of the position of the moraine of 1849 CE, which was described by H. Abich [1]. The highest and most clearly shaped lateral moraine, conventionally called the "17th century moraine", was formed earlier than the end of the 16th century (tree-ring minimum age). The oldest tree in the valley (1598 CE) was found at the "forested island" end moraine (2294 m asl). Judging by the size of the lichens Rhizocarpon geographicum (120-130 mm) on this surface the moraine may be several centuries older. We re-examined the trunk of a pine which was discovered in the 1960s buried in the fluvio-glacial sediments presumably formed in 1880s (historical descriptions). It was dated earlier by radiocarbon (140 +/- 75 BP [2] (calibrated date - 1650-1960 CE). According to the ring width cross-dating, the most probable dates of the buried tree are 1759-1883 CE, however, the second likely dates are 1826-1950 CE. Suppressions of pine growth at the forefields of the Greater Azau in the 1640s, 1710s, 1800s, 1840s-1860s CE are synchronous with the advances of the Bosson, Mer de Glace and Grindelwald glaciers in the Alps [2]. Three soil horizons buried in the moraine of the Greater Azau glacier were identified in the artificial outcrop on the left side of the valley (N43.26583, E42.4767, 2370 m asl). The uppermost horizon located 0.6 m below the surface of the moraine is a thin layer of loam developed in a short time interval (130±20 BP (IGAN ams - 6826) 1680-1939cal BP (charcoal). Two lower thicker horizons (buried 13 and 15 m below the surface) indicate longer periods of continuous soil formation lasting for about 720 years (between 774-89 CE and 1496-1641 CE) and for 1750 years (between ca 3 ka BP and 7-8 centuries CE), respectively. They both are well developed soils formed within the loam layers without detrital material, containing a thick dark humus horizon with a high content of soil organic matter, as well as fragments of charcoal and tree bark. During these three periods, the glacier was relatively small.References1. Abich H., Geologische Beobachtungen auf Reisen im Kaukasus um Jahre 1873. Moskau, 1875. 138 p.2. Nussbaumer S., Zumbühl H. The Little Ice Age history of the Glacier des Bossons (Mont Blanc massif, France): A new high-resolution glacier length curve based on historical documents. Climatic Change, 111, 2012. 301-334 pp.

One of the important problems in studying processes on the Earth has to do with monitoring animal migrations. ICARUS equipment installed in ISS RS supports global animal migrations monitoring from space. The ICARUS equipment was developed under the Cooperation Agreement between the German Aerospace Center (DLR) and the state corporation Roscosmos (hereinafter referred to as the Agreement). Under this agreement the Russian space experiment Uragan is combined with the German project ICARUS (International Cooperation for Animal Research Using Space). The ICARUS equipment is a system consisting of the onboard and ground segments. The onboard segment includes the control computer OBC-I (OnBoard Computer ICARUS), intended for data storage and processing, and the antenna unity which provides transmission of trajectory data on the ISS spatial position to miniature transceiving sensors (tags) attached to the animals that are being monitored, as well as reception of data from the tags about coordinates of the movement of birds and animals during their seasonal migration. The ground segment includes multiple small (with the mass of up to 5 g) transceivers (tags) which are attached on the ground to migrating animals and birds. These tags may also record additional sensor information such as 3D-body acceleration, 3D-magnetometer data, temperature, pressure and humidity. Some data from the tags will be transmitted on a daily basis to the Mission Control Center in Moscow (MCC-M) via high-rate data link of the radio data transmission system to be further passed on to user centers in Germany and Russia. Most recorded sensor data will be stored on the tag memory for terrestrial readout using handheld receivers on the ground.

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A nonparametric clustering method, the Bagging Voronoi K-Medoid Alignment algorithm, which simultaneously clusters and aligns spatially/temporally dependent curves, is applied to study various data series from the Elbrus region (Central Caucasus). We used the algorithm to cluster annual curves obtained by smoothing of the following synchronous data series: titanium concentrations in varved (annually laminated) bottom sediments of proglacial Lake Donguz-Orun; an oxygen-18 isotope record in an ice core from Mt. Elbrus; temperature and precipitation observations with a monthly resolution from Teberda and Terskol meteorological stations. The data of different types were clustered independently. Due to restrictions concerned with the availability of meteorological data, we have fulfilled the clustering procedure separately for two periods: 1926–2010 and 1951–2010. The study is aimed to determine whether the instrumental period could be reasonably divided (clustered) into several sub-periods using different climate and proxy time series; to examine the interpretability of the resulting borders of the clusters (resulting time periods); to study typical patterns of intra-annual variations of the data series. The results of clustering suggest that the precipitation and to a lesser degree titanium decadal-scale data may be reasonably grouped, while the temperature and oxygen-18 series are too short to form meaningful clusters; the intercluster boundaries show a notable degree of coherence between temperature and oxygen-18 data, and less between titanium and oxygen-18 as well as for precipitation series; the annual curves for titanium and partially precipitation data reveal much more pronounced intercluster variability than the annual patterns of temperature and oxygen-18 data.

The Institute of Geography, Russian Academy of Sciences (RAS), was founded in Petrograd in 1918 as the Industrial-Geographical Department of the Commission for Studying Natural Production Forces. In 1934, it was moved to Moscow and renamed the Institute of Physical Geography of the USSR Academy of Sciences and then (in 1936) the Institute of Geography of the USSR Academy of Sciences. Its history included all stages of the development of the national geography, beginning from the traditions of the late 19th and early 20th centuries, when the concept of geography as a descriptive science was given up and its branch specialization began, until the formation of geography of the 21st century as a paradigm and synthetic discipline with great prospects for developing knowledge. The modern geography and the Institute of Geography of the Russian Academy of Sciences use a wide range of interdisciplinary remote and field methods, the latest tools, and laboratory analyses to understand the quickly changing world, its nature, the population, and the economy retrospectively, at the present time, and in the future. The results of the research performed at the Institute was published in the Vestnik RAS periodical many times.

The projected climate change in the 21st century is expected to affect various forest ecosystems with corresponding ecological, economic, and social impact. Adaptation measures for forestry need to be planned well in advance, because the forests being regenerated today will have to cope with future climate conditions in long time periods. Here we use a process-based forward model of tree growth, VS-Lite, calibrated and independently validated on tree-ring data and forced by climate projections according to various greenhouse gas emission scenarios. We estimate the ensemble radial tree growth of pine in Povolzhie region in the future. Our projections show a constant tree growth throughout the 21st century. The increased temperature will slightly favour the tree growth, especially in the case of an extended growth season, while mostly constant precipitation will not lead to any soil moisture deficit. The results of this study are crucial for the development of Povolzhie region in the near or remote future.

Arctic driftwood represents a unique proxy archive at the interface of marine and terrestrial environments. Combined wood anatomical and dendrochronological analyses have been used to detect the origin of driftwood and may allow past timber floating activities, as well as past sea ice and ocean current dynamics to be reconstructed. However, the success of driftwood provenancing studies depends on the length, number, and quality of circumpolar boreal reference chronologies. Here, we introduce a Eurasian-wide high-latitude network of 286 ring width chronologies from the International Tree Ring Data Bank (ITRDB) and 160 additional sites comprising the three main boreal conifers Pinus, Larix, and Picea. We assess the correlation structure within the network to identify growth patterns in the catchment areas of large Eurasian rivers, the main driftwood deliverers. The occurrence of common growth patterns between and differing patterns within catchments indicates the importance of biogeographic zones for ring width formation and emphasizes the degree of spatial precision when provenancing. Reference chronologies covering millennial timescales are so far restricted to a few larch sites in Central and Eastern Siberia (eastern Taimyr, Yamal Peninsula and north-eastern Yakutia), as well as several pine sites in Scandinavia, where large rivers are missing though. The general good spatial coverage of tree-ring sites across northern Eurasia indicates the need for updating and extending existing chronologies rather than developing new sites.

No tree-ring chronologies were reported so far in the International Tree Ring Data Bank for the central part of the East-European Plain. This absence is traditionally explained by the lack of motivation for tree-ring research in this area. Indeed, due to the intense anthropogenic press the old trees are rare in this region and the climatic signal embedded in the ring width is not strong and is always complex. In this study we present the new tree-ring network of 9 ring width chronologies of pine ( Pinus sylvestris ) up to 297 years long in a large region of about 450 km in diameter in the Central Russia (54–57N, 33–40E) and analyze their climatic response. Tree ring growth in the region is controlled by both temperature and precipitation of vegetation period, and all the analyzed chronologies have signifi cant correlation with summer PDSI values (with coeffi cients up to r ≤0.4). All of them were sampled after the year 2010 when a severe summer drought spread over the European part ofRussia. This allowed spatial analysis of 2010 year annual ring (and rings related to the years of other known severe droughts of 20th century) in the context of drought impact on tree growth. This study is a starting point for constructing large tree ring network for further investigation of severity and spatial distribution of droughts in European Russia in the past.

The results of dendrochronological and radiocarbon dating by means of accelerator mass spectrometry (AMS) of six medieval icons, originating from northern European Russia and painted on wooden panels made from Scots pine, dated to the 15th to 17th centuries are presented. The panels of each icon were studied using dendrochronology. Five to six AMS dates were obtained for four icons. Although five icons were dendro-dated successfully, one failed to be reliably cross-dated with the existing master tree-ring chronologies and it was dated by radiocarbon wiggle-matching. Dendrochronological dating and wiggle-matching of radiocarbon dates allowed us to determine the narrow chronological intervals of icon creation.

The review outlines the main aspects of the use of pectin polysaccharides in medicine, both as independent medicinal substances and as a material for creating systems for targeted delivery of drugs, as well as for regenerative medicine and biomedical engineering. A number of studies demonstrate that pectin polysaccharides are physiologically active substances with immunomodulating properties, including anti-inflammatory activity, they lower cholesterol and triglyceride in the blood serum, normalize glucose metabolism, bind and remove toxins and radionuclides from the body, regulate work and provide protection of the gastrointestinal tract, have anticarcinogenic and antimetastatic effects.

Climate change projected for the 21st century is expected to affect different forest ecosystems with corresponding ecological, economic, and social impacts. Modeling is extensively used to estimate the impacts of climate change on tree species distributions, but only several studies produced tree growth projections based on climate change scenarios. However, those studies have been based on multiple regression models without considering the basic principles of dendroclimatology – principle of limiting factors and uniformitarian principle. Here we describe the methodology for tree growth projections that takes advantage of the process-based forward model of tree growth, VS-Lite, calibrated and independently validated on tree-ring data and driven by climate projections. We further use this methodology for spruce growth projections on Solovetskiye islands according to two extreme greenhouse gases emissions scenarios. Even according to the conservative one, which is peak-and-decayscenario, tree growth is projected to be significantly higher throughout the 21st century, than in the 20th century. These results are crucial for the strategies of Arctic region development in the near and remote future.

Bottom sediments of the proglacial Lake Donguz-Orun situated at ∼2500 m a.s.l. in the Elbrus Region (Central Caucasus) reveal regular laminae, characteristic of proglacial varved lakes. This is the first laminated sediment sequence recorded in the region. However, visual counting of the layers was restricted due to partial indistinctness of the lamination. In order to confirm the annual sedimentary cyclicity and proceed with annually resolved data, in addition to the visual identification we used high-resolution geochemical markers. The upper 160 mm of the sediment core were scanned at 200 μm intervals using synchrotron radiation X-ray fluorescence analysis (SR-XRF). Additional ultrahigh resolution scanning at 30 μm increments was employed for the upper 20 mm of the core. The Rb/Sr and Zr/Rb ratios are interpreted to record annual changes in grain-size. Based on this geochemical assessment, we identified 88 annual layers covering the interval between 1922 and 2010, while visually we have been able to identify between 70 and 100 layers. The correctness of the geochemical results is confirmed by mean accumulation rates assessed by 137Cs and 210Pb dating. Cross-correlation between the ring width of local pine chronology and the layer thickness, identified as a distance between the annual Rb/Sr peaks, allowed for the accurate dating of the uppermost preserved year of the sediment sequence (AD 2010). Annually averaged elemental data were then compared with regional meteorological observations, glacier mass balance and tree-ring chronologies. The comparison revealed notable conformities: content of bromine is positively correlated with annual temperatures (r = 0.41, p < 0.01), content of terrigenous elements (major elements with the origin in watershed rocks) is positively correlated (up to r = 0.44, p < 0.01) with annual precipitation. A high statistically significant negative relationship is observed between the concentrations of terrigenous elements and tree-ring width of local pine chronology (up to r = -0.56, p < 0.01). Taken together, these data point to a common composite climatic signal in the two independent records (lake sediments and tree rings) and confirm that the laminae represent annual layers (i.e., varves). These findings open opportunities for high-resolution multiproxy climate reconstructions 300–350 years long using the longer sediment core and tree-ring records.

In mid and high latitudes, the stable isotope ratio in precipitation is driven by changes in temperature, which control atmospheric distillation. This relationship forms the basis for many continental paleoclimatic reconstructions using direct (e.g. ice cores) or indirect (e.g. tree ring cellulose, speleothem calcite) archives of past precipitation. However, the archiving process is inherently biased by intermittency of precipitation. Here, we use two sets of atmospheric reanalyses (NCEP (National Centers for Environmental Prediction) and ERA-interim) to quantify this precipitation intermittency bias, by comparing seasonal (winter and summer) temperatures estimated with and without precipitation weighting. We show that this bias reaches up to 10 °C and has large interannual variability. We then assess the impact of precipitation intermittency on the strength and stability of temporal correlations between seasonal temperatures and the North Atlantic Oscillation (NAO). Precipitation weighting reduces the correlation between winter NAO and temperature in some areas (e.g. Québec, South-East USA, East Greenland, East Siberia, Mediterranean sector) but does not alter the main patterns of correlation. The correlations between NAO, δ18O in precipitation, temperature and precipitation weighted temperature are investigated using outputs of an atmospheric general circulation model enabled with stable isotopes and nudged using reanalyses (LMDZiso (Laboratoire de Météorologie Dynamique Zoom)). In winter, LMDZiso shows similar correlation values between the NAO and both the precipitation weighted temperature and δ18O in precipitation, thus suggesting limited impacts of moisture origin. Correlations of comparable magnitude are obtained for the available observational evidence (GNIP (Global Network of Isotopes in Precipitation) and Greenland ice core data). Our findings support the use of archives of past δ18O for NAO reconstructions.

This review summarises landform records and published age-estimates (largely based upon tephrochronology) to provide an overview of glacier fluctuations upon the Kamchatka Peninsula during the Holocene and, to a lesser degree, earlier phases of glaciation. The evidence suggests that following deglaciation from the Last Glacial Maximum (LGM), the peninsula experienced numerous phases of small-scale glacial advance. During the Late Glacial, moraine sequences appear to reflect the former presence of extensive glaciers in some parts of the peninsula, though little chronological control is available for deposits of this period. During the Holocene, the earliest and most extensive phase of advance likely occurred sometime prior to c. 6.8 ka, when glaciers extended up to 8 km beyond their current margins. However, these deposits lack maximum age constrains, and pre-Holocene ages cannot be discounted. Between c. 6.8 ka and the onset of ‘Neoglaciation’ c. 4.5 ka, there is little evidence of glacial advance upon the peninsula, and this period likely coincides with the Holocene climatic optimum (or ‘hypsithermal’). Since c. 4.5 ka, numerous moraines have been deposited, likely reflecting a series of progressively less extensive phases of ice advance during the Late Holocene. The final stage of notable ice advance occurred during the Little Ice Age (LIA), between c. 1350 and 1850 C.E., when reduced summer insolation in the Northern Hemisphere likely coincided with solar activity minima and several strong tropical volcanic eruptions to induce widespread cooling. Following the LIA, glaciers upon the peninsula have generally shown a pattern of retreat, with accelerated mass loss in recent decades. However, a number of prominent climatically and non-climatically controlled glacial advances have also occurred during this period. In general, there is evidence to suggest that millennial scale patterns in the extent and timing of glaciation upon the peninsula (encompassing much of the last glacial period) are governed by the extent of ice sheets in North America. Millennial-to-centennial scale fluctuations of Kamchatkan glaciers (encompassing much of the Holocene) are governed by the location and relative intensity of the Aleutian Low and Siberian High pressure systems. Decadal scale variations in glacier extent and mass balance (particularly since the LIA) are governed by inter-decadal climatic variability over the North Pacific (as reflected by the Pacific Decadal Oscillation), alongside a broader trend of hemispheric warming.

Cores of bottom sediments from epiglacial Donguz-Orun Lake (Cis-Elbrusian, Northern Caucasus) have been studied. Here we present descriptions of the sampling techniques, sample preparation, and analytical procedures by the X-ray fluorescence method. The sedimentation rate, estimated by calculation of peaks of the Rb/Sr ratio as well as employing isotope concentrations of 137Cs and 210Pb in the upper parts of the core, permitted us to assume the annual character of the regularly laminated sediment. A statistically significant correlation between the concentration variations of certain chemical elements and their groups in the sediment against normalized meteorological data from the Terskol meteorological station has been revealed. This makes the studied object applicable for development of high resolution palaeoclimate reconstructions.

Field investigations showed that the leeward slopes across the Kuznetsky Alatay Mountains (also the windward slopes in the Tigertysh ridge) are intensively eroded by glaciers and represent the classical type of “alpine-type landscape”. Accumulative glacial landforms are developed in all types of glacial valleys. Study of five valleys (the Karatas, the Lower and the Upper Tayzhasu, Perekhodnya, the right source of the Small Kazyr Rivers) showed that four stadial moraine complexes can be identified. These moraines are very different by their morphology. They indicate the change of glaciation from large ancient valley glaciers to modern small cirque and slope glaciers. In this article, the first data are assessed about evolution of glaciers and climate in the Kuznetsky Alatay Mountains from the Last Glacial Maximum of Late Pleistocene (between 26,500 and 19,000–20,000 years BP) to nowadays on the basis of studies of glacial landforms, sedimentology, and biostratigraphy. In the Glacier inventory complied in 1970s-early 1980s, 91 glaciers were recorded in the Kuznetsky Alatay; however, some were erroneously identified as glaciers. The review of the current changes of modern glaciation of the Kuznetsky Alatay is made on the basis of repeated photographs and direct field measurements of 30 glaciers. 18 out of the 30 studied glaciers melted away completely, their area decreased from 1.4 to 0.5–0.3 km2. Not all glaciers strongly degraded. Large cirque glaciers have not changed significantly. Over the past 110 years, the area of perennial snowfields in the Kuznetsky Alatay Mountains had reduced by 90 %. Over the century, the timberline has risen by about 50 m and is currently located at 1220–1200 m a.s.l.

A contribution to the PAGES Asia2k working group. ABSTRACT: To investigate climate variability in Asia during the last millennium the spatial and temporal evolution of summer (June–July–August; JJA) temperature in eastern and south central Asia is reconstructed using multi proxy records and the regularized expectation maximization (RegEM) algorithm with truncated total least squares (TTLS) under a point by point regression (PPR) framework. The temperature index reconstructions show that the late 20th century was the warmest period in Asia over the past millennium. The temperature field reconstructions illustrate that temperatures in central eastern and southern China during the 11th and 13th centuries and in western Asia during the 12th century were significantly higher than those in other regions and comparable to levels in the 20th century. Except for the most recent warming all identified warm events showed distinct regional expressions and none were uniform over the entire reconstruction area. The main finding of the study is that spatial temperature patterns have on centennial time scales varied greatly over the last millennium. Moreover seven climate model simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) over the same region of Asia are all consistent with the temperature index reconstruction at the 99 confidence level. Only spatial temperature patterns extracted as the first empirical orthogonal function (EOF) from the GISS E2 R and MPI ESM P model simulations are significant and consistent with the temperature field reconstruction over the past millennium in Asia at the 90 confidence level. This indicates that both the reconstruction and the simulations depict the temporal climate variability well over the past millennium. However the spatial simulation or reconstruction capability of climate variability over the past millennium could be still limited. For reconstruction some grid points do not pass validation tests and reveal the need for more proxies with high temporal resolution accurate dating and sensitive temperature signals especially in central Asia and before AD 1400.

Using instrumental archives, aerial photographs, satellite images, old maps, descriptions of early explorers and old photographs we identified and mapped nine front positions of the Ullukam Glacier (SW slope of Elbrus) for the period from the end of XIX to the early XXI centuries. In 1884–2009 glacier retreated by 775 m. It advanced from 1971 to 1987 (36 m). The glacier fluctuations in the previous period were reconstructed using geomorphologic data, lichenometry, modern and buried soil description and radiorarbon analyses. We identified three Little Ice Age moraines of almost equal magnitude when the Ullukam Glacier was 889 m longer than in 2009. Two later advances occurred in the first third to middle of XIX century and in 1870s The recent fluctuations of the Ullukam Glacier closely correspond to the retreat two other glaciers in Elbus area. The location of the buried soil in the valley of Ullukam glacier brings evidence that the glacier have not advanced lower than 2813 m a.s.l. at least during the last four thousand years.

A global overview of glacier advances and retreats (grouped by regions and by millennia) for the Holocene is compiled from previous studies. The reconstructions of glacier fluctuations are based on 1) mapping and dating moraines defined by 14 C, TCN, OSL, lichenometry and tree rings (discontinuous records/time series), and 2) sediments from proglacial lakes and speleothems (continuous records/ time series). Using 189 continuous and discontinuous time series, the long-term trends and centennial fluctuations of glaciers were compared to trends in the recession of Northern and mountain tree lines, and with orbital, solar and volcanic studies to examine the likely forcing factors that drove the changes recorded. A general trend of increasing glacier size from the earlyemid Holocene, to the late Holocene in the extra-tropical areas of the Northern Hemisphere (NH) is related to overall summer temperature, forced by orbitally-controlled insolation. The glaciers in New Zealand and in the tropical Andes also appear to follow the orbital trend, i.e., they were decreasing from the early Holocene to the present. In contrast, glacier fluctuations in some monsoonal areas of Asia and southern South America generally did not follow the orbital trends, but fluctuated at a higher frequency possibly triggered by distinct teleconnections patterns. During the Neoglacial, advances clustered at 4.4e4.2 ka, 3.8e3.4 ka, 3.3e2.8 ka, 2.6 ka, 2.3e2.1 ka, 1.5e1.4 ka, 1.2e1.0 ka, 0.7e0.5 ka, corresponding to general cooling periods in the North Atlantic. Some of these episodes coincide with multidecadal periods of low solar activity, but it is unclear what mechanism might link small changes in irradiance to widespread glacier fluctuations. Explosive volcanism may have played a role in some periods of glacier advances, such as around 1.7e1.6 ka (coinciding with the Taupo volcanic eruption at 232 ± 5 CE) but the record of explosive volcanism is poorly known through the Holocene. The compilation of ages suggests that there is no single mechanism driving glacier fluctuations on a global scale. Multidecadal variations of solar and volcanic activity supported by positive feedbacks in the climate system may have played a critical role in Holocene glaciation, but further research on such linkages is needed. The rate and the global character of glacier retreat in the 20th through early 21st centuries appears unusual in the context of Holocene glaciation, though the retreating glaciers in most parts of the Northern Hemisphere are still larger today than they were in the early and/or mid-Holocene. The current retreat

While paleoclimatic studies have extended our understanding of North Pacific climate variability, these have been almost exclusively based on proxies from western North America. We present a tree-ring reconstruction of June to September coastal air temperatures for Nemuro, northeastern Japan for the past four centuries. It explains 36% of the variance in instrumental temperatures and correlates significantly with indices of the atmosphere–ocean circulation. Spectral analyses reveal robust bidecadal peaks that appear associated with regional modes of western North Pacific variability. At decadal time scales, Nemuro temperatures appear to be influenced by the confluence of the Kuroshio and Oyashio currents, a primary centre of action driving Pacific Decadal Variability. Regime shifts (e.g. 1976) are weakly expressed relative to western North America. These aspects of western North Pacific climate are regionally distinct relative to those elsewhere in the basin, with greater complexity than can be attributed to the Pacific Decadal Oscillation (PDO) alone.

Kamchatka���s forests span across the peninsula���s diverse topography and provide a wide range of physiographic and elevational settings that can be used to investigate how forests are responding to climate change and to anticipate future response. Birch (Betula ermanii Cham.) and larch (Larix gmelinii (Rupr.) Kuzen) were sampled at eight new sites and together with previous collections were compared with monthly temperature and precipitation records to identify their climate response. Comparisons show that tree-ring widths in both species are primarily influenced by May through August temperatures of the current growth year, and that there is a general increase in temperature sensitivity with altitude. The ring-width data for each species were also combined into regional chronologies. The resulting composite larch chronology shows a strong resemblance to a Northern Hemisphere (NH) tree-ring based temperature reconstruction with the larch series tracking NH temperatures closely through the past 300 years. The composite birch ring-width series more closely reflects the Pacific regional coastal late summer temperatures. These new data improve our understanding of the response of forests to climate and show the low frequency warming noted in other, more continental records from high latitudes of the Northern Hemisphere. Also evident in the ring-width record is that the larch and birch forests continue to track the strong warming of interior Kamchatka.

Along with Arctic amplification, changes in Arctic hydroclimate have become increasingly apparent. Reanalysis data show increasing trends in Arctic temperature and precipitation over the 20th century, but changes are not homogenous across seasons or space. The observed hydroclimate changes are expected to continue, and possibly accelerate, in the coming century, not only affecting pan-Arctic natural ecosystems and human activities, but also lower latitudes through changes in atmospheric and oceanic circulation. However, a lack of spatiotemporal observational data makes reliable quantification of Arctic hydroclimate change difficult, especially in a long-term context. To understand hydroclimate variability and the mechanisms driving observed changes, beyond the instrumental record, climate proxies are needed. Here we bring together the current understanding of Arctic hydroclimate during the past 2000 years, as inferred from natural archives and proxies and palaeoclimate model simulations. Inadequate proxy data coverage is apparent, with distinct data gaps in most of Eurasia and parts of North America, which makes robust assessments for the whole Arctic currently impossible. Hydroclimate proxies and climate models indicate that the Medieval Climate Anomaly (MCA) was anomalously wet, while conditions were in general drier during the Little Ice Age (LIA), relative to the last 2000 years. However, it is clear that there are large regional differences, which are especially evident during the LIA. Due to the spatiotemporal differences in Arctic hydroclimate, we recommend detailed regional studies, e.g. including field reconstructions, to disentangle spatial patterns and potential forcing factors. At present, it is only possible to carry out regional syntheses for a few areas of the Arctic, e.g. Fennoscandia, Greenland and western North America. To fully assess pan-Arctic hydroclimate variability for the last two millennia additional proxy records are required.

A new ring-width record from the eastern flanks of the Eastern Sakhalin Range, Sakhalin Island, Russian Federation is significantly correlated with summer temperatures and allows for the reconstruction of May–July average temperatures for the past 400 years. The reconstruction explains 37 % of the variance in May–July temperatures and shows a strong cooling between 1680 and 1710 CE coincident with the Maunder solar minimum and in agreement with other independent tree-ring reconstructions and glacier histories from sites along the margin of the Sea of Okhotsk. While recent decades are among the warmest in the record they are rivaled by periods centered on 1650 and 1850 CE. Warming in the observational record and the reconstruction is consistent with the influence of the declining strength of the Siberian High and loss of sea ice over the same interval. Decadal (17–25 year) variability persists throughout the reconstruction. At interannual timescales the Sakhalin reconstruction is most strongly correlated with local and central North Pacific sea surface temperatures over the past 120 years, whereas at decadal timescales there is an additional association with Asian land surface temperatures.

We present here the results of spruce (Picea schrenkiana Fish. et May.) tree-ring research in the Tien Shan Mountains, Kirgiz Republic. We explore the connection between climatic parameters and spruce ring width and maximum density at the upper and lower tree limits and provide two reconstructions: the May-August temperature reconstruction from 1626 to 1995 based on a multi-site composite maximum density chronology from the upper tree limit and the drought index reconstruction from 1680 to 2000 based on the lower tree limit regional ring width chronology. The ring width chronologies from the upper and lower tree limits show a strong similarity. They both depend to a large extent on moisture availability. The maximum density chronology does not correlate with them: it depends on different climatic parameters, namely on the summer temperature. The correlations of the reconstructions with CRU TS3 temperature and precipitation grid point data confirm the results of the modeling using the meteorological data from the nearest stations. The 20th century does not look unusual in the context of the last three hundred years in the Tien Shan Mountains, either in terms of the drought occurrence and severity or in summer temperature changes. However the reconstruction does not encompass the last decade when the summer warming in Tine Shan has been especially prominent. In contrast, some change in precipitation is indicated with the 19th century being drier in the Issyk Kul region compared to the 20th century.

Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century. At multi-decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them. There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between AD 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century. The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions. Recent warming reversed the long-term cooling; during the period AD 1971?2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years. Fil: Ahmed, Moinuddin. Federal Urdu University of Arts, Science and Technology. Department of Botany; Pakistán Fil: Anchukaitis, Kevin J.. Columbia University. Lamont Doherty Earth Observatory; Estados Unidos. Woods Hole Oceanographic Institution; Estados Unidos Fil: Asrat, Asfawossen . Addis Ababa University. School of Earth Sciences; Etiopía Fil: Borgaonkar, Hemant P.. Indian Institute of Tropical Meteorology; India Fil: Braida, Martina . University of Trieste. Dipartimento di Matematica e Geoscienze; Italia Fil: Buckley, Brendan M. . Columbia University. Lamont Doherty Earth Observatory; Estados Unidos Fil: Ulf Büntgen. Swiss Federal Research Institute WSL; Suiza Fil: Chase, Brian M.. Université Montpellier. Département Paléoenvironnements et Paléoclimats (PAL); Francia. University of Bergen. Department of Archaeology, History, Cultural Studies and Religion; Noruega Fil: Christie, Duncan A. . Universidad Austral de Chile. Laboratorio de Dendrocronología y Cambio Global; Chile. Universidad de Chile. Center for Climate and Resilience Research; Chile Fil: Cook, Edward R.. Columbia University. Lamont Doherty Earth Observatory; Argentina Fil: Curran, Mark A. J.. Australian Antarctic Division; Australia. University of Tasmania. Antarctic Climate & Ecosystems Cooperative Research Centre; Australia Fil: Diaz, Henry F. . National Oceanic and Atmospheric Administration. Cooperative Institute for Research in Environmental Sciences, ; Estados Unidos Fil: Esper, Jan. Johannes Gutenberg University. Department of Geography,; Alemania Fil: Fan, Ze-Xin . Chinese Academy of Sciences. Xishuangbanna Tropical Botanical Garden ; China Fil: Gaire, Narayan P. . Nepal Academy of Science and Technology. Faculty of Science,; Nepal Fil: Ge, Quansheng. Chinese Academy of Sciences. Institute of Geographical Sciences and Natural Resources Research, ; China Fil: Gergis, Joëlle. University of Melbourne. School of Earth Sciences; Australia Fil: González-Rouco, J Fidel. Universidad Complutense de Madrid. Departamento Astrofísica y CC de la Atmósfera; España Fil: Goosse, Hugues. Université Catholique de Louvain. LemaitreCenter for Earth and Climate Research, Earth and Life Institute; Bélgica Fil: Grab, Stefan W. . University of the Witwatersrand. School of Geography,Archaeology and Environmental Studies; Sudáfrica Fil: Graham, Nicholas. Hydrologic Research Center; Estados Unidos Fil: Graham, Rochelle . Hydrologic Research Center; Estados Unidos Fil: Grosjean, Martin . University of Bern. Oeschger Centre for Climate Change Research & Institute of Geography; Suiza Fil: Hanhijärvi, Sami T.. University of Helsinki. Department of Environmental Sciences; Finlandia Fil: Kaufman, Darrell S.. Northern Arizona University. School of Earth Sciences and Environmental Sustainability; Estados Unidos Fil: Kiefer, Thorsten . International Project Office, Past Global Changes (PAGES); Suiza Fil: Kimura, Katsuhiko. Fukushima University. Department of Symbiotic System Science; Japón Fil: Korhola, Atte A.. University of Helsinki. Department of Environmental Sciences; Finlandia Fil: Krusic, Paul J.. Stockholm University. Department of Physical Geography and Quaternary Geology; Suecia Fil: Lara, Antonio. Universidad Austral de Chile. Laboratorio de Dendrocronología y Cambio Global; Chile. Universidad de Chile. Center for Climate and Resilience Research; Chile Fil: Lézine, Anne-Marie. Université Pierre et Marie Curie. Laboratoire d’Océanographie et du Climat: Expérimentations et Approches Numériques (LOCEAN); Francia Fil: Ljungqvist, Fredrik C.. Stockholm University. Department of History, ; Suecia Fil: Lorrey, Andrew M.. National Institute of Water and Atmospheric Research Ltd., National Climate Centre Auckland; Nueva Zelanda Fil: Luterbacher, Jürg. Justus Liebig University. Department of Geography, Climatology, Climate Dynamics and Climate Change; Alemania Fil: Masson-Delmotte, Valérie . Laboratoire des Science du Climat et de l’Environnement, Gif-sur-Yvette; Francia Fil: McCarroll, Danny. Swansea University. Department of Geography; Reino Unido Fil: McConnell, Joseph R.. Nevada System of Higher Education. Desert Research Institute; Estados Unidos Fil: McKay, Nicholas P.. Northern Arizona University. School of Earth Sciences and Environmental Sustainability; Estados Unidos Fil: Morales, Mariano Santos. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Moy, Andrew D.. Australian Antarctic Division; Australia. University of Tasmania. Antarctic Climate & Ecosystems Cooperative Research Centre; Australia Fil: Mulvaney, Robert. British Antarctic Survey; Reino Unido Fil: Mundo, Ignacio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Nakatsuka, Takeshi. Nagoya University. Department of Earth and Environmental Sciences; Japón Fil: Nash, David J.. University of the Witwatersrand. School of Geography,Archaeology and Environmental Studies; Sudáfrica. University of Brighton. School of Environment and Technology; Reino Unido Fil: Neukom, Raphael . Swiss Federal Research Institute WSL; Suiza Fil: Nicholson, Sharon E.. Florida State University. Department of Earth, Ocean and Atmospheric Sciences, ; Estados Unidos Fil: Oerter, Hans. Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association. Department of Glaciology; Alemania Fil: Palmer, Jonathan G.. University of Exeter. College of Life and Environmental Sciences; Reino Unido. University of New South Wales. Climate Change Research Centre; Australia Fil: Phipps, Steven J.. University of New South Wales. Climate Change Research Centre; Australia. University of New South Wales. ARC Centre of Excellence for Climate System Science; Australia Fil: Prieto, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Rivera, Andres. Centro de Estudios Cientificos; Chile Fil: Sano, Masaki. Nagoya University. Department of Earth and Environmental Sciences; Japón Fil: Severi, Mirko. University of Florence. Department of Chemistry ‘Ugo Schiff’; Italia Fil: Shanahan, Timothy M.. University of Texas at Austin. Jackson School of Geosciences; Estados Unidos Fil: Shao, Xuemei. Chinese Academy of Sciences. Institute of Geographical Sciences and Natural Resources Research; China Fil: Shi, Feng. Chinese Academy of Sciences. LASG, Institute of Atmospheric Physics, ; China Fil: Sigl, Michael . Nevada System of Higher Education. Desert Research Institute,; Estados Unidos Fil: Smerdon, Jason E.. Columbia University. Lamont Doherty Earth Observatory; Estados Unidos Fil: Solomina, Olga N. . Russian Academy of Sciences. Institute of Geography; Rusia Fil: Steig, Eric J.. University of Washington. Department of Earth and Space Sciences; Estados Unidos Fil: Stenni, Barbara. University of Trieste. Dipartimento di Matematica e Geoscienze; Italia Fil: Thamban, Meloth. National Centre for Antarctic and Ocean Research; India Fil: Trouet, Valerie. University of Arizona. Laboratory of Tree-Ring Research; Estados Unidos Fil: Turney, Chris S.M.. University of New South Wales. Climate Change Research Centre; Australia Fil: Umer, Mohammed. Addis Ababa University. School of Earth Sciences; Etiopía Fil: van Ommen, Tas. Australian Antarctic Division; Australia. University of Tasmania. Antarctic Climate & Ecosystems Cooperative Research Centre; Australia Fil: Verschuren, Dirk. Ghent University. Department of Biology; Bélgica Fil: Viau, Andre E.. University of Ottawa. Department of Geography; Canadá Fil: Villalba, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Vinther, Bo M.. University of Copenhagen. Niels Bohr Institute; Dinamarca Fil: von Gunten, Lucien . Past Global Changes (PAGES). International Project Office, ; Suiza Fil: Wagner, Sebastian. Helmholtz-Zentrum Geesthacht. Institute for Coastal Research; Alemania Fil: Wahl, Eugene R.. National Oceanic and Atmospheric Administration. National Climatic Data Center; Estados Unidos Fil: Wanner, Heinz. University of Bern. Oeschger Centre for Climate Change Research & Institute of Geography; Suiza Fil: Werner, Johannes P.. Justus Liebig University. Department of Geography, Climatology, Climate Dynamics and Climate Change; Alemania Fil: White, James W.C.. University of Colorado. Institute of Arctic and Alpine Research; Estados Unidos Fil: Yasue, Koh. Shinshu University. Department of Forest Science; Japón Fil: Zorita, Eduardo. Helmholtz-Zentrum Geesthacht. Institute for Coastal Research; Alemania

A global compilation of glacier advances and retreats for the past two millennia grouped by 17 regions (excluding Antarctica) highlights the nature of glacier fluctuations during the late Holocene. The dataset includes 275 time series of glacier fluctuations based on historical, tree ring, lake sediment, radiocarbon and terrestrial cosmogenic nuclide data. The most detailed and reliable series for individual glaciers and regional compilations are compared with summer temperature and, when available, winter precipitation reconstructions, the most important parameters for glacier mass balance. In many cases major glacier advances correlate with multi-decadal periods of decreased summer temperature. In a few cases, such as in Arctic Alaska and western Canada, some glacier advances occurred during relatively warm wet times. The timing and scale of glacier fluctuations over the past two millennia varies greatly from region to region. However, the number of glacier advances shows a clear pattern for the high, mid and low latitudes and, hence, points to common forcing factors acting at the global scale. Globally, during the first millennium CE glaciers were smaller than between the advances in 13th to early 20th centuries CE. The precise extent of glacier retreat in the first millennium is not well defined; however, the most conservative estimates indicate that during the 1st and 2nd centuries in some regions glaciers were smaller than at the end of 20th/early 21st centuries. Other periods of glacier retreat are identified regionally during the 5th and 8th centuries in the European Alps, in the 3rd–6th and 9th centuries in Norway, during the 10th–13th centuries in southern Alaska, and in the 18th century in Spitsbergen. However, no single period of common global glacier retreat of centennial duration, except for the past century, has yet been identified. In contrast, the view that the Little Ice Age was a period of global glacier expansion beginning in the 13th century (or earlier) and reaching a maximum in 17th–19th centuries is supported by our data. The pattern of glacier variations in the past two millennia corresponds with cooling in reconstructed temperature records at the continental and hemispheric scales. The number of glacier advances also broadly matches periods showing high volcanic activity and low solar irradiance over the past two millennia, although the resolution of most glacier chronologies is not enough for robust statistical correlations. Glacier retreat in the past 100–150 years corresponds to the anthropogenic global temperature increase. Many questions concerning the relative strength of forcing factors that drove glacier variations in the past 2 ka still remain.

In the Northern Caucasus, glacier and climatic variations over the past centuries remain insufficiently documented. In this review, we summarized the high-resolution information on glacier and climate fluctuations in the region for the past millennium and provided a synthesis of these two lines of evidence with respect to regional climate change. The key areas considered in the paper are the Elbrus area, the Teberda and Arkhyz valleys in the Western Caucasus and the Cherek Bezengiisky and Tsey valleys in the Eastern Caucasus, where the most paleoclimatic evidence has been retrieved. We focused on the fluctuation records of the ten glaciers that are best documented. To reconstruct changes in glacier length in the past, we used aerial photos, optical space images, repeated photographs and old maps. The ages of moraines were defined with the help of instrumental records, historical images, old maps, and tree-ring dating. Lichenometry was used as a supplementary tool to determine the relative ages of glacial landforms. We reviewed the collection of control points used for the lichenometric curves and determined the time limit of potential use of this method in the Caucasus to be up to one millennium. High-resolution tree-ring-based hydroclimatic reconstructions in the Northern Caucasus are presented based on the reconstruction of June–September temperature (1595–2012 CE), the mass balance reconstruction of the Garabashi Glacier (1800–2008 CE) and the runoff of the Teberda River (low-frequency variations) for May, July and August for 1850–2005 CE. The synthesis of all the available paleoclimatic records revealed several distinct climatic periods. Evidence of a warm interval (traditionally referred to as the “Arkhyz break in glaciation”) preceding the Little Ice Age (LIA) in the Caucasus is based on archeological, palynological, geochemical and pedological data. However, the conclusions concerning the duration and magnitude of this warming are still vague due to the low resolution of the data available and ambiguous interpretation of the evidence. The first LIA maximum glacier extent in the past millennium is poorly constrained. According to our data, it occurred prior to the year 1598 CE (tree-ring-based minimum age). Two other major phases of advances occurred in the second half of the 17th century CE and the first half of 19th century CE. General glacier retreat in the Northern Caucasus started in the late 1840s CE, with four to five minor readvances in the 1860s–1880s CE and three readvances or steady states in the 20th century CE (1910s, 1920s and 1970s–1980s). Since the last LIA maximum in the middle of the 19th century CE, most glaciers have decreased in length by more than 1000 m, and the rise in the elevation of the glacier fronts has exceeded 200 m. The glacier advances correspond to summer temperature minima and are generally coherent with the reconstructed mass balance of the Garabashi Glacier. A comparison of a tree-ring-based summer temperature reconstruction in the Northern Caucasus with detailed reconstructions of summer temperature and glacier fluctuations in the Alps shows a pronounced agreement between the records and supports the similarity between the patterns of climatic and glacier variations in the two regions.