Проблемы Арктики и Антарктики
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Ранний диагенез донных осадков пресноводных озер острова Вайгач
Get PDFThe paper presents results of studying the diagenetic transformation of bottom sediments from two freshwater lakes — Talatinskoe and Tundrovoe — in the Vaigach Island. The study of biogeochemical processes in the conditions of present-day climate instability is especially important for Arctic water ecosystems, since their environmental sustainability is extremely low, and the effects of global warming are most significant. According to available climate forecasts, the Vaigach Island is located in the zone of maximum changes in natural complexes. The lake-river systems of the island are unique island geosystems, but to date they are poorly understood.Our aim was to carry out comprehensive research on the biogeochemical processes of the sulfur cycle as the geochemical aspect of the bacterial sulfate reduction process, which involves the conjugation of the cycles of carbon, sulfur and iron, participating in redox processes that play an important role in sedimentation and early diagenesis. In order to achieve this goal, a multi-method (hydrochemical, geochemical, etc.) approach was developed using standard generally approved laboratory practices adapted to the study goals.Based on the pollen data, it was found that the formation of the bottom sediments of Lake Talatinskoe occurred in the current climatic conditions of the tundra. The data on the distribution of grain size fractions allow us to conclude that the sediment sequences of both lakes undergo regular destruction and mixing during seasonal freezing-thawing. This was reflected in the random distribution of all the parameters studied and in the impossibility of determining the sedimentation rate. The data obtained on the quantitative characteristics of sulfate reduction parameters (reduced compounds, forms of reactive iron, the amount of organic matter and its qualitative composition), their distribution and transformation indicate a low intensity of redox processes in precipitation. The most likely reason for this is the high degree of humification of the terrigenous organic matter and the low temperatures of the microorganisms’ habitat.Приведены результаты комплексных исследований процессов диагенетического преобразования донных осадков пресноводных озер о. Вайгач - Талатинское и Тундровое. Установлено (по данным спорово-пыльцевого анализа), что формирование донных отложений оз. Талатинское происходило в современных климатических условиях тундры. Показано, что отсутствие закономерностей в распределении всех изучаемых параметров и невозможность определения скорости осадконакопления, обусловлены перемешиванием отложений обоих озер в ходе сезонного замерзания-оттаивания. Данные о количественных характеристиках параметров сульфатредукции (соединений восстановленной серы, форм реакционноспособного железа, органического вещества), их распределении и трансформации свидетельствуют о низкой интенсивности редокс-процессов в осадках вследствие малой доступности органического вещества для микроорганизмов и суровости среды их обитания
Методика формирования архитектуры системы мониторинга ледовых нагрузок для ледостойкой самодвижущейся платформы
Get PDFThe ice-resistant self-propelled platform (IRSPP) named North Pole that is currently under construction at the JSC Admiralty Shipyards is designed to carry out year-round scientific research in the Arctic Ocean. The IRSPP will be equipped with a unique ice loads monitoring system (ILMS). The technical requirements for the ILMS were developed in the Department of Ship Performance in Ice of the AARI. The ILMS should ensure a safe operation of the IRSPP in ice conditions (operational function) and serve as a measuring tool for researching of the mechanics of deformation and destruction of ice (scientific function). Analysis of ice conditions at different stages of IRSPP operation showed that the main scenario of ice interaction with the IRSPP hull will be the action of ice under compression on the middle part of the hull during drift.The monitoring of the stress-strain state of the hull is carried out by a complex system of fiber-optic strain sensors placed on different elements of the hull structures. The largest number of sensors are located on the side plating in the middle part of the IRSPP hull. The locations of the sensors were determined by finite element analysis of the stress-strain state of the IRSPP hull under the action of ice load. To monitor the stress-strain state of the surrounding ice field, up to 16 pressure sensors frozen into the ice are provided. Also, the system receives and stores data on the angles of roll, trim, yaw of IRSPP, its longitudinal, lateral and vertical accelerations, and the surrounding hydrometeorological conditions: wind speed and direction, air temperature, atmospheric pressure, and the geographical position of the platform.ILMS will significantly improve the safety of IRSPP operation during prolonged drift in ice conditions. Besides, the ILMS provides the platform hull with the functions of a measuring tool for studying the mechanics of deformation and destruction of sea ice in interaction with the engineering structures.The main purpose of this work is to create a comprehensive system for studying the processes of ice impact on structures in order to obtain new data about the parameters and nature of ice loads.В статье описывается разработка технических требований к системе мониторинга ледовых нагрузок для ледостойкой самодвижущейся платформы (ЛСП) «Северный полюс», выполненная в отделе ледовых качеств судов ААНИИ. Процесс разработки технических требований включал в себя анализ эксплуатационных ледовых условий ЛСП, определение сценариев взаимодействия льда с корпусом ЛСП, постановку задач для системы мониторинга ледовых нагрузок (СМЛН), разработку архитектуры СМЛН, конечно-элементный анализ напряженно-деформированного состояния корпуса ЛСП, а также разработку требований к размещению датчиков на конструкциях корпуса ЛСП. Основной целью работы является создание комплексной системы исследования процессов воздействия льда на сооружения для получения новых данных по параметрам и характеру действия ледовых нагрузок
Статистические особенности экстремального дрейфа льда юго-западной части Карского моря, полученные по результатам модельных расчетов
Get PDFThe aim of the study was to identify the basic characteristics of ice drift in the south-western Kara Sea and to estimate the extreme drift speed of given probability, including its spatial variability and statistical correlation with the main drift-forming factors.In order to obtain the ice drift data, the numerical dynamic-thermodynamic model of ice cover evolution developed in AARI was used. Its basic specific feature is imitation of ice cover with the help of so-called markers (conventional ice floes). Using three variants of the model grid net (25, 12.5 and 5 km), the ice conditions in the Baidara Bay and the adjoining area in January-March 2018 were simulated.The analysis of the simulation results showed that the average ice drift (average ice transport) is directed from the Baidara Bay to the open sea, i.e. northward with slight deviations mostly to the west. A less detailed grid net results in a smoothed ice drift field, while an increase in the spatial resolution of the model increases the spatial contrasts of the ice drift.The maximum values of the extreme ice drift velocity expressed as “once per N years” occur in the northern part of the model area at the directions of the north-western quarter (up to 1.5-1.8 m/s “once per 10 years” - “once per 100 years”, respectively). The frequency of ice drift velocity exceeding 0.3 m/s is about 4-7 %, and that of ice drift velocity exceeding 0.6 m/s is not more than 1 %.At low drift velocity, the role of inertia is very high, but as the drift rate grows, the inertia contribution decreases noticeably. At increasing drift velocity, the statistical correlation between the ice drift (on the one hand) and the wind, current and sea level tilt (on the other hand) becomes evident. This effect is especially evident for the correlation “drift / wind”. The correlation “drift / ice pressure” depends on the drift speed more or less noticeably at low and high drift speeds, when unidirectional changes of the ice drift and ice pressure happen more often than the opposite ones. At the drift velocities within 0.15-0.60 m\s, the correlation between the ice drift and ice pressure is insignificant, i.e. the unidirectional and opposite changes of the ice drift and ice pressure are almost equally likely.Для выявления основных параметров дрейфа льда в юго-западной части Карского моря и получения оценок экстремальных скоростей дрейфа заданной обеспеченности, включая статистическую связь с основными дрейфообразующими факторами, была использована разработанная в ААНИИ численная динамико-термодинамическая модель эволюции ледяного покрова.С помощью модели была воспроизведена эволюция ледяного покрова в юго-западной части Карского моря за 3 месяца 2018 г. для трех вариантов пространственного разрешения: 5 км, 12,5 км и 25 км. Для трех специально выбранных точек были получены статистические оценки дрейфа льда, включая экстремальные значения заданной обеспеченности в терминах «1 раз в N лет». Были вычислены парные коэффициенты корреляции скорости дрейфа льда с основными влияющими на дрейф факторами в разных диапазонах скоростей, что позволило оценить изменение вклада каждого фактора в зависимости от скорости дрейфа. Показано, что, по мере увеличения скорости дрейфа, наиболее сложным образом меняется статистическая связь между дрейфом и сжатием льда. Выявлены основные черты влияния пространственной детализации модели на статистические оценки экстремального дрейфа
Сообщества водорослей водоемов оазиса Ширмахера, Восточная Антарктида
Get PDFIn continental waterbodies of Antarctic oases specific algal communities are forming. The structure and dominating complex of species of this communities due to different distance from the seashore and latitude, the composition of the constituent rocks, altitude and the presence in the past of periods of contact with sea water is unique for different oases. It may vary in different waterbodies within one oasis besides.Aim of the research is to describe different types of algal communities from the continental waterbodies of Schirmacher Oasis and it’s confinement to the different types of waterbodies.Samples were collected from 173 waterbodies: 151 with stagnant water and 22 streams.During the study 64 species of Cyanoprokaryotes were found, and this group usually dominated in communities. Also 14 most frequent species of Chlorophyta, 12 most frequent species of Bacillariophyta, 6 species of desmid algae, 2 species of Xanthophyceae, 1 species of Eustigmatophyceae were noted in benthos. Usually resting stages and in one case — life cells of Golden algae (Chrysophyceae, Synurophyceae) were found in mats on the bottom of big lakes. Plankton algae in most of the waterbodies had very low abundance and diversity and were strongly influensed by trophic level. Benthic algal communities were much more diverse and abundant. Eight sustainable types of benthic algal communities were revealed in continental waterbodyes of Schirmacher Oasis. Form, colour, and species composition of bentic films and mats strongly depended on temperature, conductivity and pH of the waterbody and its depth.Континентальные водоемы антарктических оазисов содержат специфические сообщества водорослей. Целью исследования было изучение и описание различных типов сообществ водорослей континентальных водоемов оазиса Ширмахера (Земля Королевы Мод) и выявление их приуроченности к различным типам водоемов. Пробы были отобраны из 173 водных объектов: 151 со стоячей водой и 22 ручьев.В результате проведенного исследования была выявлена разнообразная по видовому составу альгофлора. Основная часть выявленных таксонов была зафиксирована в сообществах водорослей бентоса, которые образуют маты и скопления разного цвета, толщины и структуры. В континентальных водоемах оазиса Ширмахера выделено 8 регулярно встречающихся типов бентосных сообществ водорослей, распределение которых зависит от типа водоема и глубины. Отмечены бедный видовой состав и низкая численность фитопланктона большинства исследованных озер оазиса, их зависимость от антропогенного фактора
Опыт дистанционного температурно-влажностного зондирования атмосферы в период дрейфа НЭС «Академик Трешников»
Get PDFFor the first time experience was gained with the operation of Russian equipment for water content and temperature remote sensing of the lower atmosphere in the Arctic. The comparison the results of measurements by radiometric systems with data of radiosoundings in wide range of meteorological conditions had been executed. It is shown that mean difference between integral atmospheric water content, measured by water vapor radiometer WVR, and calculated from radiosoundings data does not exceed 6 % with standard deviation 0.54 kg/m2 and significant correlation coefficient 0,92. Analysis the data of meteorological temperature profiler MTR-5 allows to conclude that in general its adequately reproduce air temperature profiles in the atmospheric lower 1000 m layer. Some deviations take place only in cases of large temperature gradients. Preliminary analysis of WVR data showed that monthly mean value of integral atmospheric water content in area under study in April 2019 year practically coincides with calculated from radiosoundings, performed in 1983—1988 years at the polar station Barentsburg, nearest to the drift region, 3.61 and 3.62 kg/m2 respectively. Same time hourly mean values of integral atmospheric water content during drift varied from 2 to 10 kg/m2, with extreme values recorded between April 15 and April 20, probably due to intensive transport of air masses of the Atlantic origin. Based on MTR-5 data it was concluded that despite differences in sounding technology, the place and time of observations, the statistics of inversions registered during drift correspond well to statistics of inversions, recorded on the Arctic coastal stations and over sea ice cover of the Weddell Sea in winter.Приведено описание работы комплекса аппаратуры влажностно-температурного дистанционного зондирования нижнего слоя атмосферы (радиометр РВП и метеорологический профилемер МТР-5РЕ) в условиях Арктики. Выполнено сравнение результатов измерений радиометрических систем с данными аэрологического зондирования в широком спектре метеорологических условий. Получены оценки интегрального влагосодержания атмосферы и характеристик инверсий в нижнем 1000-метровом слое атмосферы в период дрейфа НЭС «Академик Трёшников» в северной части Баренцева моря
Приливы в южной части Карского моря в районе о. Белый
Get PDFA number of promising hydrocarbon deposits are known in the south-western part of the Kara Sea. A safe development of these deposits requires hydrometeorological support, including sea-level observations. The paper deals with sea-level data of autonomous anchored buoy station. The period of observation is about 2 years, and the observation dataset is divided into 2 periods due to the displacement of the buoy station. The coordinates of the first position of the buoy station are known but they had been changed after the displacement (possibly due to the action of the ice ridge keels).Data from two time series of observations are studied by harmonic analysis, using the method of least squares by AARI version. According to the average monthly and mean annual values of the main tides it is found that the data includes two independent series. It is determined that the second series may be considered uniform. In order to locate of the anchored buoy station we calculated new coordinates using the empirical tidal charts of the M2 wave.As a result, the harmonic constants of the eight main tidal waves for the Belyi Island area are presented for the first time. The new data confirms the amphidromic system in tides O1 and Q1 , between the Zhelaniya Cape and the Belyi Island. According to the new data the maximum seasonal variation in the range of M2 tide was observed in June, and the minimum of the phase angle was observed in July. This unusual seasonal variation of the M2 tide corresponds to previous observations data from the Uedinenia Island.The authors have no competing interests
Проблемы пространственного развития регионов севера Дальнего Востока России: социологический анализ
Get PDFThe purpose of the article is to identify the features and problems of spatial development of the regions of the North of the Russian Far East. The research was carried out under the project “Modeling the spatial development scenarios of Siberia and the Far East of Russia until 2030: features of the resettlement system” (RFBR grant No. 19-010-00836 A), which won the RFBR competition “Fundamental Scientific Research Projects”. The study is being conducted by the team of the Department of Geourbanistics & Spatial Development of ISPR FCTAS RAS since 2019 and is intended to last for three years. The main goal is to assess the current state of the resettlement system, develop strategic prospects and model alternative scenarios for the spatial development of the regions of the Siberian and Far Eastern Federal Districts. A key feature is the use of interdisciplinary methods based on a combination of economic, mathematical, sociological, statistical and scenario approaches to research. From a practical point of view, the project results will help to plan more rationally the spatial development the spatial development of the country’s regions. The analysis shows that the sociological methods of spatial research have large reserves but are not yet used to the full capacity. This article discusses the current problems of spatial development of the north of the Russian Far East. On the basis of the authors’ development of the empirical research model by a group of scientists of ISPR FCTAS RAS, in August 2019, the survey of respondents of the Kamchatka Krai, the Magadan Oblast` and the Chukotka Autonomous Okrug was conducted. The results of the opinion poll made it possible to identify differences in migration preferences, a number of features of the economic potential capacity and the quality of infrastructure, and the social sphere of the Far Eastern regions of the country
