Table 4 - available via license: Creative Commons Attribution 4.0 International
Content may be subject to copyright.
Hurst exponent for climatic characteristics according to the data from 20 weather stations in the southern Russia.
Source publication
The study of climate, in such a diverse climatic region as the Caucasus, is necessary in order to evaluate the influence of local factors on the formation of temperature and precipitation regimes in its various climatic zones. This study is based on the instrumental data (temperatures and precipitation) from 20 weather stations, located on the terr...
Contexts in source publication
Context 1
... results of calculations of the Hurst exponent for determining the trend-persistence of precipitation and temperature series are presented in Table 4. Table 4 shows that the persistence indicators for temperature trends significantly exceeded the values for precipitation, and it characterizes the persistence and long-term changes in the temperature regime. ...
Context 2
... results of calculations of the Hurst exponent for determining the trend-persistence of precipitation and temperature series are presented in Table 4. Table 4 shows that the persistence indicators for temperature trends significantly exceeded the values for precipitation, and it characterizes the persistence and long-term changes in the temperature regime. The highest persistence trends have been observed at average annual, summer temperatures (H = 0.80), and autumn temperatures (H = 0.73). ...
Context 3
... annual sums of precipitation, in 27% of the steppe stations studied and in 10% of foothill stations, they decreased, for all other meteorological stations an increase was observed in annual sums of precipitation. In this case, Table 4 shows that in the autumn, for all stations the highest Hurst exponent value was observed both for the sum of precipitation and for the daily maximums H = 0.63, which characterized the persistence of the identified trends for a long period. ...
Similar publications
In this paper we investigate the time trend coefficients in snowpack percentages by watershed in Colorado, US, allowing for the possibility of long range dependence or long memory processes. Nine series corresponding to the following watersheds are examined: Arkansas, Colorado, Gunnison, North Platte, Rio Grande, South Platte, San Juan-Animas-Dolor...
Citations
... All these challenges are also characteristic of the mountainous regions of the Caucasus. Over the past 30-40 years, the Caucasus has seen an increase in annual and seasonal temperatures, especially in summer, by an average of 0.5-0.7°C, a drier climate, and a growing frequency and intensity of meteorological extremes (Assessment 2022; Kozachek et al. 2017;Shvarev et al. 2021;Tashilova et al. 2019). Rapid glacier retreat (Solomina et al. 2024;Tielidze et al. 2022;Toropov et al. 2019) has cut off a lot of water in places where it is already scarce, such as the South Caucasus and the eastern flank of the North Caucasus. ...
In agricultural mountain regions, changes in weather patterns force people to look for new agricultural activities, shift from agriculture to tourism services, or even leave the mountains. This study discusses the role of Dagestan’s agricultural terraces as a potential resource for mountain people to adapt agricultural activities to climate change, thereby demonstrating the community resilience grounded on local traditional practices. We selected eight mountainous administrative districts of Dagestan as a case study area and tracked the changes of average annual, summer, and winter temperatures and precipitation for different altitudes in 2011–2020 compared to 2000–2010. We also conducted 30 informal exploratory interviews with local farmers and officials (purposive sampling) aiming at revealing common local narratives regarding climate change and its impact on agricultural activities, including the use of terraces. According to our results, respondents perceive the warming and drying of the Dagestan mountains as a growing water scarcity due to decreased precipitation and reduced snow cover, and as an opportunity to expand agricultural activities to higher altitudes. Agricultural terraces are seen as a prime land resource, preventing erosion and conserving soil moisture. Including terraces as a tourist attraction could increase interest in the local landscape and its history and may also indirectly serve to strengthen the resilience of local communities. While climate change may make it difficult to farm in the mountains, tourism becomes an additional source of income for farmers and supports agriculture.
... Эльбруса, её суммарное сокращение за указанный выше период составило 2.8%. Наблюдающиеся изменения климата в регионе , Tashilova et al., 2019 и деградация оледенения Северного Кавказа (Kutuzov et al., 2019, Toropov et al., 2019 привели к значительным изменениям речного стока (Rets et al., 2020). Начиная с конца 1980-х -начала 1990-х годов наблюдается снижение расходов воды в июле и августе на 2-6% за 10 лет, даты прохождения максимальных расходов воды смещаются на более ранние сроки, и увеличиваются среднемесячные расходы июня . ...
In this study, we adapted the ECOMAG model of the runoff formation for analysis of the Terek River basin using comprehensive hydrometeorological information as well as data on soils, landscape, and glaciation. To take account of regional characteristics of the glaciation, the additional ice module was used with the model. This improvement has resulted in a satisfactory agreement between the modeled runoff hydrographs and the observed ones. In our simulations we used the updated glacier cover predictions from the- global glaciological model GloGEMflowdebris together with regional climate projections from the CORDEX experiment to determine possible future changes in the Terek River flow in the 21st century. The results show that the runoff will change between −2% and +5% according to the RCP2.6 scenario, and from −8% to +14% in the RCP8.5 scenario. The directedness of the runoff changes in particular subbasins of the River will essentially depend on the altitude position of the snow and glacier feeding zones, that is responsible for the intensity of their degradation. Thus, in the RCP8.5 scenario, the flow of the Chegem River will begin to decrease significantly in the second half of the 21st century. In contrast, the predicted increasing of the runoff in Malka and Baksan rivers, which are primarily fed by meltwater from glaciers and snow on Elbrus and other high-mountain zones, is expected to be continued until the end of the century. But this increase may be caused only by a growth of a part of the snowmelt feeding due to greater winter precipitation. The model estimates confirm the present-day observed trends within the intra-annual runoff distribution, demonstrating the earlier start of the spring flood, a decrease in summer runoff volumes and then its increase in the autumn months. The results of the research may be used for more efficient management of water resources in the North Caucasus in the future, including electricity generation and water supply.
... The results obtained regarding trends in annual temperature and precipitation in southern Russia are consistent with the results of other studies. Tashilova et al. (2019), the Republic of Dagestan. In addition to climatic factors, anthropogenic influences, such as excessive pasture digression, significantly contribute to the formation of "islands" of desertification, as indicated by Zolotokrylin's (2019) study. ...
Climate change is a global problem that is accompanied by the significant changes in humidification conditions in many regions all over the world. The study examined spatiotemporal changes in humidification zones in southern Russia in the period 1961–2020. Humidification zones were determined in accordance with the classification of the Selyaninov hydrothermal coefficient. During the research period, a significant increase in average annual temperatures was noted for the region (+ 0.31 °C/decade) and generally positive, but insignificant, dynamics of annual precipitation (+ 4.80 mm/decade). These changes were accompanied by a significant shift in the humidification zones. Despite some periods of decline, the territories of semi-desert and desert zones, as well as dry steppes, have significantly expanded from the east of the region to the west in the last decade. The expansion of these zones was primarily due to a reduction in the area of the more humid steppe zone, with a lesser contribution from the forest-steppe zone. Overall, during the study period, the area of semi-desert and desert zone expanded by an average of + 5.505 thou km2/decade. The zone of the Taiga and deciduous forests has not undergone significant changes. The results obtained indicate arid warming and a general deterioration in humidification conditions in most of southern Russia in the period 1961–2020. According to calculations, further warming, other things being equal, can lead to an even greater expansion of the semi-desert and desert bioclimatic zone, which can provoke a number of socio-economic and environmental problems, especially in the eastern part of the region.
... The climate is continental with average annual air temperature ranging between 2.5 °C in the alpine zone and 8.05 °C in the whole Elbrus district (Tashilova et al. 2019), annual precipitation is 500-724 mm, up to 1100 mm at high altitudes (Razumov 2003). For the alpine zone and floodplain grass meadows with the dominance of Festuca pratensis are typical while on the slopes of gorges, pine trees (Pinus sylvestris) and birch (Betula pendula) forests can be found (Tsepkova et al. 2015). ...
The study of cryoconite – a specific organomineral sediment on the glacier surface – is essential to estimate environmental processes and sustainability, biogeochemical cycles, pollution rate and degree of human influence under conditions of climate change and diverse anthropogenic activities. Key chemical and physical features such as pH values, total organic carbon and hot-water extractable carbon content, microbial respiration, and particle-size distribution, as well as the content of some trace elements and pollution indices have been determined in materials sampled at the Mt. Elbrus region. The results obtained showed accumulation of easily decomposable carbon and correlated with it high rate of microbial respiration at the Garabashi Glacier, despite the low content of total organic carbon (max. 0.92%) due to its redistribution. Cryoconites at the Garabashi Glacier also efficiently accumulated trace elements, especially Zn (max. 55.40 mg kg− 1) and Pb (max. 26.03 mg kg− 1), up to high pollution level. Domination of silt and sand fractions indicated major role of autochthonous transfer to the glacial zone both from anthropogenic and natural geologic sources. Translocation of cryoconite material to the periglacial zone and anthropogenic activities led to accumulation of both total organic carbon and hot-water extractable carbon as well as trace elements such as Zn (max. 64.40 mg kg− 1) and Cd (max. 0.41 mg kg− 1) in studied Leptosols. Migration of elements from the glacial to the periglacial zone at the Elbrus region can accelerate developments of soils after glacier retreat, while intensification of human activity may pose additional pollution risks for agriculture, tourism and environmental sustainability.
... A decrease in precipitation can significantly accelerate negative processes. However, several studies show a generally positive trend in annual precipitation for southern Russia has (Ashabokov et al. 2017;Popova and Popov 2020;Tashilova et al. 2019). An increase in precipitation intensity has also been reported. ...
... Our conclusion about the increase in total amount of precipitation in the South of Russia in recent decades is consistent with the findings from several other studies (Ashabokov et al. 2017;Popova and Popov 2020;Tashilova et al. 2019). For example, Vyshkvarkova (2021) also indicated a 2022). ...
The study analyzed spatiotemporal trends in the amount, heterogeneity, and extremeness of precipitation in the South of Russia in the period 1960–2022. The highest annual precipitation, at 1634 mm, occurs along the Black Sea coast of the Caucasus. As one moves north and east, precipitation noticeably decreases to a minimum value of 216 mm in the Ergeninskaya Upland and the western part of the Caspian Lowland. The spatial distribution of seasonal precipitation correlates with this spatial pattern. Almost throughout the entire study areas, a positive but mostly insignificant trend in annual precipitation was observed with an average growth rate of 5.25 mm/decade. However, growth tendency were only observed in winter, autumn and spring, with average rates of 1.46, 3.77 and 2.45 mm/decade, respectively. An increase in the unevenness of precipitation during the year was observed mostly in the western part of the Caspian Lowland and on the Ergeninskaya Upland. Extreme precipitation indicators (SDII, R10mm, Rx1day, Rx5day) varied from minimum values in the west of the Caspian Lowland to maximum values on the Black Sea coast (4.85–14.0 mm/day, 4.5–52.2 days, 25.4–90 mm, 36.0–166.8 mm, respectively). Changes in extreme precipitation in all seasons were mostly insignificant, but all indicators (except R10mm) showed positive dynamics (average 0.04 mm/days/decade, 0.30 and 0.63 mm/decade, respectively), and the most pronounced increase occurring in autumn. Spatially, the most pronounced increase in the number of extreme precipitations was observed on the Black Sea coast of the Caucasus.
... Despite the challenging orographic conditions, the radius of statistically significant correlation of annual precipitation (r > 0.4) measured at the weather stations encompasses the majority of the western and central Caucasus. Similar findings were reported by (Tashilova et al., 2019). The highest correlation (r ≥ 0.8) occurs within an area of 10-50 km. ...
In this study, we present a seasonally resolved accumulation record spanning from 1750 to 2009 Common Era (CE), based on a 181.8 m ice core obtained from the Elbrus Western Plateau in the Caucasus. We implemented various methods to account for uncertainties associated with glacier flow, layer thinning, and dating. Additionally, we applied a novel approach to calculate a seasonal calendar for meteorological data, enabling comparison with ice core records. The reconstructed accumulation data were compared with available meteorological data, gridded precipitation records, and paleo-reanalysis data. Reconstructed accumulation is representative for a large region south of the Eastern European plain and Black Sea region with summer precipitation being the primary driver of precipitation variability. We identified a statistically significant relationship between changes in regional precipitation and fluctuations in the North Atlantic Oscillation (NAO) index, which is, however, not stable over the entire period covered by the ice core.
... Despite the challenging orographic conditions, the radius of statistically significant correlation of annual precipitation (r > 0.4) measured at the weather stations encompasses the majority of the Western and Central Caucasus, while a physically significant radius (r > 0.6) extends to 50-100 km. Similar findings were reported by (Tashilova et al., 2019). The highest correlation (r ≥ 0.8) occurs within an area of 10-50 km, indicating that on the annual and sub-annual timescale ice-core records likely provide description of precipitation within 50-100 km radius. ...
In this study, we present a seasonal-resolution accumulation record spanning the period from 1750 to 2009 Common Era (CE), based on a 181.8-m ice core obtained from the Elbrus Western Plateau in the Caucasus. We implemented various methods to account for uncertainties associated with glacier flow, layer thinning, and dating. Additionally, we developed a novel approach to calculate a seasonal calendar for meteorological data, enabling comparison with ice core records. The reconstructed accumulation data were compared with available meteorological data, gridded precipitation records, and paleo reanalysis data. Reconstructed accumulation is representative for a large region south of Eastern European plain and Black sea region. Summer precipitation was found to be the primary driver of precipitation variability. We identified a statistically significant but unstable in time relationship between changes in precipitation in the region and fluctuations of the North Atlantic Oscillation (NAO) index.
... The Caucasus mountain massif is a natural barrier to moistureladen air masses, which results in intensive deposition of fallout radionuclides (Efimov and Anisimov 2011;Ivanov et al. 2022;Kordzadze et al. 2013;Tashilova et al. 2019). As soon as fallout radionuclides ( 210 Pb ex , 137 Cs, 241 Am) fall onto the earth surface, they are sorbed by the soils and sediments. ...
Natural and artificial radioactivity of bottom sediment in the six lakes of the Western and Central Caucasus have been evaluated. It allowed to define the variation of sedimentation rate during the last 100–150 years using technogenic (¹³⁷Cs) and natural (²¹⁰Pb, ²²⁶Ra) radionuclides as a chronomarkers. The studied lakes are located in the contrasting geographic conditions, different orographic positions, and have different origin. The average annual precipitation in the area of each of the lakes has been detected to stay relatively constant during the ¹³⁷Cs fallout period, while the air temperature has markedly increased during the last decades. The detected sedimentation rates are the indirect indicator of climate change in the mountains. They are slightly decreasing owing to the increased protection of soil by vegetation cover in the lower altitude zone; in the upper zones, they are growing due to accelerated glacier retreat. The radioecological situation is estimated as normal. High levels of ¹³⁷Cs (33 kBq m⁻²) and ²⁴¹Am (0.1 kBq m⁻²) in bottom sediments are attributed to the region-specific geographical characteristics.
... At the same time, the tendencies towards a decrease in the amount of precipitation prevail on the territory [Yin et al., 2018]. It was found that across Russia the number and duration of periods without rain increased in the summer [Tashilova et al., 2019]. ...
The study focuses on the local dynamics of precipitation and temperature in the mountainous regions of the Dagestan Republic (North Caucasus, eastern part). A shift in the secondary maximum of the precipitation annual distribution in the low-mountainous part of the region from August to September was found. The wettest years in the highlands in the periods 1966--1978 and 1996--2013 are discovered. The period from the beginning of the current century until now is identified as the wettest in the low-mountain zone. It was found that the trends of seasonal temperatures are positive. At the same time, the dynamics of spring temperatures remained insignificant in the low-mountain zone until 2010. It was revealed that the statistically reliable increase of temperature in February and March and unidirectional tendencies in the daily characteristics of precipitation is the local pattern of the climate change in this part of the North Caucasus. In this season the increase in the average and maximum daily precipitation intensity is reliable.
... The determination of 241 Am (a daughter radionuclide 241 Pu) is an alternative to radiocaesium dating, which allows the identification of the 1963 peak in the accumulative strata corresponding to the period of maximum bomb-derived fallout (Appleby et al., 1991;Arnaud et al., 2006;Oldfield et al., 1995;Arnaud et al., 2006;Appleby, 2002;Lusa et al., 2009;Corcho-Alvarado et al., 2014). High mountain systems, such as the Caucasus, acting as barriers to the migration of air masses (Barry, 1992;Efimov and Anisimov, 2011) leads to the formation of high precipitation on the windward slopes (Kononova, 2015;Tashilova et al., 2019), and intense and uneven accumulation of FRN in soil (Stewart et al., 1959;Lance et al., 1986;Bunzl and Kracke, 1988;UNSCEAR, 1993;Blagoeva and Zikovsky, 1995;Wright et al., 1999;Kvasnikova et al., 1999). It is assumed that there are two sources of radionuclide inputs in Caucasus: bomb-derived fallout during nuclear weapons tests with a maximum fallout in 1963 (UNSCEAR, 1982;Hirose et al., 1987), and Chernobyl fallout from April-May 1986, (Izrael et al., 1996;De Cort, 1998). ...
The purposes of this study are to determine the content and origin of anthropogenic fallout radionuclides (FRN)
in soils of Mount Khuko, located in the western sector of the Caucasus Mountains and to assess the possibility to
use them for evaluation of sediment redistribution for the alpine grasslands,.
The field study was carried out in August 2019 near the top of Mount Khuko, located in the western part of the
main Caucasus Mountain Ridge. Integral and incremental soil samples were collected from the different
morphological units of the studied area. The content of 137Cs and 241Am in soil samples was evaluated using
laboratory gamma-spectrometry. A part of samples was selected for Pu isotopes extraction and then alphaspectrometric analysis.
It was established that the 137Cs contamination of soils in the studied area has at least two sources of origin.
The first source is the 137Cs bomb-derived fallout after the bomb tests in 1950–60th, which is widespread across
the globe. The second source is 137Cs Chernobyl-derived fallout High random variability (Cv = 25–42%) was
found within reference sites, located at the undisturbed areas on the local flat interfluves due to high variability
of soil characteristics (grain size, density, organic matter content etc.). However minimum spatial variability
(range 12,2–14,3 kBq/m2
) was identified for the mean value of 137Cs inventories for all 5 reference sites located
in the different parts of the studied area. It is difficult to separate individual peaks of the bomb-derived and
Chernobyl-derived 137Cs falloutin sediment sinks with low sedimentation rates.
Application 239,240Pu as an additional chronological marker allows to identify the origin of above mention
peaks in the soils of alpine grasslands and of dry lake bottom.
