Изменчивость ледяного покрова в Печорском море и её корреляция с температурой поверхности Баренцева моря по данным спутниковых наблюдений и реанализа

Variability of the Pechora Sea ice cover and the Barents Sea surface temperature during the season from October to June in 2002–2022 (except the season of 2011/2012) was studied on the basis of satellite observations and reanalysis ERA5. Influence of the sea surface temperature on the ice cover was also analyzed but without considering the other hydrometeorological parameters. Areas of the sea ice cover characteristics were calculated using data on the sea ice closeness obtained from the Advanced Microwave Scanning Radiometer 2 measurements. To analyze the variability of sea surface temperature, we used the average daily data of the European Centre for Medium-Range Weather Forecasts ERA5 reanalysis obtained by averaging hourly data. To study the spatial and temporal variability of sea ice cover and sea surface temperature, fields of daily averaged parameters were mapped. These maps and values of areas of the sea ice cover were analyzed. This made possible to reveal regularities of development of the sea ice processes in the Pechora Sea, to calculate the general trend of the sea ice area change over the considered period of time, and to divide the Barents Sea into four sectors with significantly different average values of the sea surface temperature: southwestern, northwestern, southeastern, northeastern ones. The seasonal and interannual variabilities of the Pechora Sea ice cover and the Barents Sea surface temperature were analyzed. To study the effect of sea surface temperature in different sectors of the Barents Sea on the sea ice area, the method of statistical analysis (Pearson’s linear correlation) was used for the monthly average data and the data, averaged over the sea ice season (from October to June) with different time lags. Significant correlation coefficients were obtained only for a two-month lag. With such a lag, high values of the inverse correlation coefficients were revealed between the sea surface temperature in the southwestern (up to –0.8) and northwestern (up to –0.6) sectors of the Barents Sea and sea ice area of the Pechora Sea, while in other sectors the correlation was significantly smaller or even below the significance level.  В работе анализируется изменчивость площади морского льда в Печорском море по данным спутникового пассивного микроволнового зондирования и температуры поверхности Баренцева моря в его разных районах по данным реанализа ERA5 за 2002–2022 гг. Выявлена значительная корреляция между этими параметрами при использовании временнóго лага в два месяца и температуры Баренцева моря в его юго-восточном и юго-западном районах

Пространственно-временнáя неоднородность значений δ18O и структуры снежной толщи на территории метеообсерватории МГУ

The isotopic composition (δ18O values) of snow layers, constructing snow cover to the time of reaching maximum snow water equivalent (SWE), was compared with the isotopic content of snow precipitated over the whole the winter season 2018/19 on the territory of the Meteorological Observatory of the Lomonosov Moscow State University (Moscow, Russia). Snow-sampling was carried out in a trench 20 m long simultaneously with detailed measurements of spatial variability of the structural characteristics of snow depth. Sampling was conducted for each precipitation event over the winter season, with the amount of precipitation also documented. It was found that the spatially-distributed enrichment with heavy oxygen isotopes along the trench fell within the range of 0–3.5‰, with average values for the four main formed snow layers changing from 1.3 to 2.5‰. The enrichment was not much dependent on the age of snow layer in the snowpack, and it was even more pronounced in the upper layers. This suggests that the post-precipitated change in the isotopic composition of snow cover for the conditions of the investigated site mainly took place when the snow was exposed to the atmosphere (due to sublimation and evaporation), while the processes of dry and wet metamorphism were either less important or even led to leveling the effects of isotopic fractionation. A positive correlation was found between the isotope composition of snow and the spatially varying snow density in each layer. This is most probably related to involvement of wind influence into the snow accumulation resulting in more dense snow. The spatial variability of the isotope composition of snow in each layer was smaller than changes in snow density and snow water equivalent.Представлены результаты сравнения изотопного состава (значений δ18O) разновозрастных слоёв снега, слагающих снежную толщу к моменту максимального водозапаса, с изотопным составом осадков, сформировавших эти слои в течение зимнего сезона 2018/19 г. на территории метеообсерватории МГУ. Установлено, что ожидаемое утяжеление изотопного состава от времени выпадения до времени отбора образцов практически не зависело от возраста слоёв

Антропогенное влияние на микроклимат и оледенение Кунгурской Ледяной пещеры в период максимальной туристической нагрузки

The Kungur Ice Cave is visited by thousands of tourists every year, so the question of anthropogenic influence on changing its state is acute. Snow and ice formations are the main attraction of the cave. From the moment of discovery and improvement of the cave, the thickness of glaciation began to depend not only on natural, but also on technical and anthropogenic conditions. First, this is a change in the temperature of the outside air, the annual rise of underground and surface waters (the Sylva River), the construction of inlet and outlet tunnels, artificial ventilation, and the number of tourists. To assess the impact of the flow of tourists on the microclimatic characteristics of the Cave, the staff of the Kungur Stationary Laboratory conducted research during the period of maximum anthropogenic load in the summer of 2022. The data analyzed in this article made it possible to clarify that the existing tourist load has an insignificant impact on the microclimate of the Cave. After the passage of each group of tourists, the air temperature in the grottoes slightly increases (by a maximum of 0.1–0.2°C) but is restored during the daytime within 4–12 minutes, and at night the temperature regime is completely restored. The maximum tourist load per day is 825–925 people or more, depending on the operating mode of the Cave. Thus, the visiting regulations and the allowed throughput of the cave are currently chosen correctly. The number of tourists is not so large as to limit the visit to the Cave to protect the ice formations, especially since the first-year ice is renewed every winter.По данным проведённых в летнее время исследований в Кунгурской Ледяной пещере, во время максимальной туристической нагрузки, сделаны выводы об антропогенном влиянии на микроклимат и оледенение пещеры. Рассмотрены основные виды воздействия человека на подземную среду, особое внимание уделено тепловому воздействию на изменение температурного режима и масштаба оледенения в существующих условиях эксплуатации Кунгурской Ледяной пещеры

Последнее оледенение и ледниково-подпрудные озера в юго-восточной части Горного Алтая

The palaeogeographic scheme of the distribution of glaciers and ice-dammed lakes in the Altai during the last global glaciation (MIS-2) was compiled based on a detailed large-scale geomorphological survey. Analysis of geomorphological traces of glaciers of this time indicates that they occupied smaller areas than those of the first Late Pleistocene glaciation. By this means, the ice dams created by them were smaller that resulted in small sizes of ice-dammed lakes. The preserved levels of terraces indicate that during the first Late Pleistocene glaciation in the Kurai-Chuya depression system the ancient lake was the only one with a level of 2250 m and a total volume of 1.70 km3. During the second Late Pleistocene glaciation in the south-east Gorny Altai, another separate lake existed which was the Bartal-Kurai Lake with a level of 1700 m and a volume of 45 km3. This lake was dammed by the Mashey Glacier, which descended from the northern slopes of the North Chuaya Range. In the Chuya Depression, the existence of a landslide-dammed lake with a volume of 0.7 km3 and a level 1.750 m has been found. Its formation was not associated with glaciers of the MIS-2 stage. Direct dating of the last ice-dammed lake in the Chuya Depression with a level of 1950 m and a volume of 140 km3 has not yet been determined. This lake was dammed by the Kuehtanar Glacier, which descended from the southern slope of the Kurai ridge. The volume of ice-dammed waters of the MIS-2 time was an order of magnitude smaller than it was in the first Late Quaternary glaciation. This explains the much lower intensity of erosive and accumulative processes associated with the mega-flood occurred due to the breakthrough of the lakes during MIS-2.Составлена палеогеографическая схема распространения ледников и ледниково-подпрудных озёр времени последнего глобального похолодания (МИС-2) на основе детальной геоморфологической съёмки крупного масштаба. Реконструированы уровни и объёмы ледниково-подпрудных озёр во время первого и второго позднеплейстоценового оледенения, а также завально-подпрудного озера, формирование которого не связано с ледниками эпохи МИС-2

Толщина и объём ледников массива Монгун-Тайга, Алтай, в 2021 г. по данным георадиолокации и моделирования

This article presents the results of estimating the scale of the present-day glaciation of the Mongun-Taiga Mountain range (Eastern Altai) based on the decoding multi-time satellite images, GPR data and modelling using GlabTop2 and the Volume-Area Scaling (VAS) method. By 2021, 38 glaciers have been identified according to the hydrological principle and 36 ones – by the morphological principle. The total area is estimated as 17.18 ± 1.13 km2. Since 2010, area of the glaciers has decreased by 15%. The thickness of the glacial complex on the main peak of the Mongun-Taiga Mountain range was measured in the ablation season of 2021. More than 6 km of profiles were obtained by the GPR survey with accuracy of about 1%. Based on these data, the GlabTop2 model was calibrated. Then the spatial distribution of the ice thickness was obtained over the entire massif. The total volume of ice in the f lat-summit glacier № 17 is estimated at 0.202 ± 0.008 km3 of ice. According to the GlabTop2 model with the morphological approach the ice volume of the whole massif was estimated at 0.733 ± 0.052 km3, and with the hydrological approach: 0.888 ± 0.061 km3. Determination of the boundaries of glaciers by the VAS method gave larger values: 0.690 ± 0.038 km3 with a morphological approach and 0.757 ± 0.036 km3 with a hydrological method. Consequently, with the same area of glaciers, volume determined by two different approaches can be rather different. This has a decisive influence on the morphological structure of ice reserves: the role of large forms of glaciation sharply prevails with the morphological approach. Most of the ice is contained in glaciers of the flat summit (27–40%). With the hydrological approach, which is used most often, the role of small forms of glaciation is overestimated. At the same time, the contribution of flat-summit glaciers is estimated at only 2%.Определены границы ледников массива Монгун-Тайга на основе гидрологического и морфологического подходов, определено сокращение площади оледенения за 2010–2021 гг. По данным георадиолокации произведена калибровка модели GlabTop2 для ледников плоской вершины. Получен диапазон значений объёма льда всего массива по модели GlabTop2, по степенным зависимостям при морфологическом и гидрологическом подходе к выделению границ ледников. Оценен вклад различных типов ледников в структуре запасов льда

Изотопно-гидрологические исследования в бассейне р. Талдура (Южно-Чуйский хребет, Центральный Алтай)

Stable isotopes investigation was carried out in the territory of the Yuzhno-Chuya Ridge (Central Altai) during the ablation season of 2022. Samples were taken to determine the contribution of meltwater and precipitation to feeding of water bodies. The main research objects are Nekrasov glacier – Tamozennoye Lake system and Taldura River. In the basin of Lake Tamozennoye, the average ice δ18O of the Nekrasov glacier (‒17.3%) was obtained. Based on the isotopic composition of ice and precipitation, it was estimated that in the stream flowing into Lake Customs, the contribution of glacier meltwater varies from 28 to 67%, on average 54%. For a stream flowing out of a lake, the proportion of meltwater is higher: 48–72, 61% on average. First of all, meltwater enters the lake by filtration through the moraine, and not by surface runoff. Along the Taldura River, δ18O does not change significantly (δ18O –16.58 … –16.84%) for 38 km before the Taldura River confluence into the Chagan River. This indicates the complete predominance of glacier meltwater in the river feeding in the middle of the ablation season. Repeated sampling of water from the Taldura River 5 km from the edge of the glacier showed, that the effect of precipitation can be traced in the isotopic composition of river water, but it does not exceed 20%.Представлены результаты изотопных исследований в долине р. Талдура. Определены изотопные характеристики льда ледника Некрасова и воды рек и ручьёв в середине сезона абляции. Показано преобладание ледникового питания на всём протяжении р. Талдура. Установлено, что талые воды менее крупного ледника Некрасова оказывают меньшее влияние на питание моренного оз. Таможенное по сравнению с влиянием талых вод ледника Большая Талдура на сток р. Талдура

Высота границы питания на куполе Беллинсгаузен, Антарктика

We present an analysis of the equilibrium line altitude (ELA) on the Bellingshausen Ice Dome on King George Island (Waterloo), Antarctica, derived only from ground-based glaciological surveys for the period 2007–2012 and 2014–2023. A good relationship was found between ELA and mean summer air temperature (XII-II months) with a coefficient of determination of about 0.8. Assuming the stability of this relation in the past, the changes in the ELA during the entire period of observations at Bellingshausen weather station (from 1968) were reconstructed. Since negative ELA values were obtained for some years, which is physically impossible, they were artificially adjusted to sea level. A good correlation of air temperature between the Bellingshausen and Deception Island weather stations allowed extending the reconstruction of ELA for a longer period (from 1947).By cleaning up the strong interannual f luctuations in ELA using five-year moving averages, two complete periods of ELA change (from minimum to minimum) were identified for approximately 20 years (1947–1968) and 45 years (1968–2013). From 2014 to present time, the third period has been continuing. At the apogee of each period, the ELA was higher than the Bellingshausen Ice Dome height, which indicates that in these years the ice dome completely lost accumulation area. For the Bellingshausen and Warsaw ice domes, a pattern of higher ELA position on the western and southern slopes compared to the eastern slopes was revealed, which is probably applicable to the entire King George Island.Since the ELA variations on King George Island are generally synchronous with its variations on Livingston Island, the reconstructed ELA on the Bellingshausen Ice Dome can probably be useful for reconstructing the glaciation history of the South Shetland Islands. Получены данные о высоте границы питания (ELA) для ледникового купола Беллинсгаузен на острове Кинг-Джордж (Ватерлоо) в Антарктике за 2007–2012 и 2014–2023 гг. Восстановлен характер изменения ELA для купола с 1947 г. по настоящее время. Выявлена синхронность изменения ELA на островах Кинг-Джордж и Ливингстон

Гляциологические исследования Института географии РАН на Эльбрусе в 2023 г

In June 2023, mass-balance and meteorological observations on Elbrus were expanded: monitoring of the Mikelchiran glacier on the northern slope of the volcano was added to the permanent observations on the southern slope (Garabashi glacier). Such synchronized observations on the opposite macro-slopes of Elbrus have not been carried out before.В июне 2023 г. были расширены масс-балансовые и метеорологические наблюдения на Эльбрусе: к постоянным наблюдениям на южном склоне (ледник Гарабаши) добавлен мониторинг ледника Микельчиран на северном склоне вулкана. Ранее подобных синхронных наблюдений на противоположных макросклонах Эльбруса не проводилось

Содержание журнала “Лёд и снег” за 2023 год

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