Том 24, № 4 (2024)
Статьи
ARCTIC WATER CURRENT IN THE BEAR ISLAND TROUGH
Аннотация
We analyzed Conductivity-temperature-depth (CTD) and moored Acoustic Doppler Current Profiler (ADCP) measurements in the western Barents Sea carried out onboard the Russian R/V Akademik Mstislav Keldysh (cruise 68) in July–August 2017. A hydrographic section in the Bear Island Trough has been made. Comparison of water properties in the trough and in the sea has been performed. We compared the tidal currents measured on the mooring with those from the TPXO9 model and found that they are quite close.
ES4001
SURFACE TRANSPORT OF TECHNICAL WATERS FROM FUKUSHIMA NPP TO THE SOUTH KURIL FISHING ZONE
Аннотация
This study explores the potential for the penetration of technical waters from the Fukushima nuclear power plant (Fukushima NPP) into the fishing areas of Russia. Using a Lagrangian approach, which examines the advection of a large number of passive markers simulating waters released from the Fukushima NPP, the typical transport pathways to the South Kuril Islands are investigated, and an estimate of the time of such transport is provided. Calculations are conducted using satellite-derived and modelled velocity fields for the test year from August 24, 2022, to August 24, 2023. This study focuses on the advection of Lagrangian markers and highlights the potential for the rapid arrival of them from the Fukushima NPP into the southern Kuril region. This article emphasizes the importance of considering the seasonal variability in Kuroshio meandering and the impact of local mesoscale vortex advection related to the propagation of Lagrangian markers from the Fukushima NPP.
ES4002
MAY 11–12 EXTREME SPACE WEATHER EVENTS BRIEF AND DOSE RATE MODEL RESPONSE
Аннотация
In this brief paper, we analyze space weather events that occurred on May 11 and 12, 2024, from the perspective of an operational space weather center that provides advisories for civil aviation. One of the key metrics monitored by the center is the radiation dose rate at operational flight altitudes. A model implemented by the center provides the dose rate in real time. The model showed that dangerous levels were momentarily exceeded just above the usual 30,000 feet level during the events. This paper highlights differences in models used by various space weather centers, emphasizing the need for harmonization.
ES4003
THE GULF STREAM STRUCTURE AND MEANDERING BASED ON THE CTD AND SADCP MEASUREMENTS IN 1989–1990 AND 2014–2015
Аннотация
An review of field studies in the Gulf Stream region carried out by the authors in two periods with a break of 25 years is presented to summarize the results. The studies in the early period included hydrographic surveys in the area of a southern meander of the Gulf Stream (1989) and in the area of dividing of a single jet of the current into separate branches: in the Gulf Stream delta (1990). The second, recent, stage includes on-route surveys with SADCP profiler in 2014–2015 while crossing the meandering Gulf Stream at mid-latitudes to study its detailed high-resolution velocity field structure.
ES4005
SATELLITE-DETECTED ANOMALOUS CHANGES IN PARAMETERS OF VARIOUS GEOPHYSICAL FIELDS DURING EARTHQUAKES OF 6 ≤ M ≤ 7.8 IN TÜRKIYE IN FEBRUARY 2023
Аннотация
Research was conducted using satellite data to study variations in parameters of various geophysical fields manifested in the lithosphere, atmosphere, and ionosphere during the preparation and occurrence of destructive earthquakes of 6 ≤ M ≤ 7.8 in Türkiye in February 2023. Precursor manifestations of these seismic events were satellite-detected in the form of anomalies in parameters of various geophysical fields, including: lineament systems, surface skin temperature and surface air temperature, relative humidity, latent heat flux, integrated flux of outgoing longwave radiation, altitude changes in ionospheric electron density, total electron content of the ionosphere, as well as aerosol optical depth. It was found that the anomalies of all studied geophysical fields detected using satellite data manifested most intensively during the period 3–13 days before the onset of seismic events.
ES4006
FREEZING PATTERNS IN SALINE SOILS: MODELING WITH REGARD TO THE OSMOTIC EFFECT
Аннотация
Freezing patterns in a porous soil saturated with a saline solution are investigated with regard to osmotic effects, using a model suggested previously by the authors but in a more general formulation. The results include a numerical and an approximate self-similar analytical solution to a nonlinear problem; description of typical freezing behavior in the presence of osmotic pressure. The modeling results agree well with experimental evidence on freezing of saline clay and sand. The model includes three porous domains with ice (I), thermodynamically equilibrated ice+solution (II), and a liquid saline solution (III) in the pores. The modeling is performed for a simplified case of domains II and III that share a mobile phase boundary where the solution freezes up partially, with heat release.
ES4008
SOLVING INVERSE MAGNETOMETRY PROBLEMS USING FUZZY LOGIC
Аннотация
Integration interpretation of geophysical anomalies is a procedure for extracting geological and geophysical information about the object under study from observed physical fields. Interpretations are closely related to solutions of systems of linear algebraic equations (SLAE), therefore the possibility of the most complete and constructive description of all solutions of SLAE is of particular importance. It will allow you to take into account all additional information about the object and obtain the highest quality interpretation. The paper presents the authors’ results on the constructive description of SLAE solutions and its application to the construction of gravimetric interpretations.
ES4004
ВЕНД-КЕМБРИЙСКИЕ ПОРОДЫ ВЕРХНЕ-КАЛАРСКОЙ ГРАБЕН-СИНКЛИНАЛИ ЮГА СИБИРСКОГО КРАТОНА: МИНЕРАЛОГИЯ И ОСОБЕННОСТИ ГЕОХИМИИ ГЛАВНЫХ ПЕТРОГЕННЫХ ЭЛЕМЕНТОВ
Аннотация
Рассматриваются особенности минерального и химического состава (главные петрогенные элементы) венд-кембрийских пород силимкунской свиты (V-Є1sl), обнажающихся на западном борту Верхне-Каларской грабен-синклинали на юго-западе Алданского щита. Изученные породы – песчаники и алевролиты, относятся к аркозам и субаркозам. По хемотипу они отвечают преимущественно нормосилитам и миосилитам. По величине щелочного модуля песчаники и алевролиты являются гиперкалиевыми и служат довольно ярким примером продуктов докембрийского аридного выветривания. Обсуждается нормативный минеральный состав, его вариации, валидность расчетов по данным петрографических исследований, проблемы использования климатических индексов и литохимических диаграмм, направленных на реконструкцию климатических параметров геологического прошлого. Значения индекса химической изменчивости CIA (Chemical Index of Alteration) песчаников и алевролитов варьируют от 49, что соответствует практически неизмененной породе, до 67 (CIAсреднее = 58). Характерные для алевролитов силимкунской свиты с высоким гидролизатным модулем (ГМ) (миосилиты) значения CIA (63–67, CIAсреднее = 65) указывают на доминирование физического выветривания во время формирования исходных для них осадков. Незначительные изменения в величине CIA для данной выборки связаны, в первую очередь, с вариациями содержание иллитного цемента и обломочного мусковита. Значения индекса химического выветривания RW (Robust Weathering) варьируются от 37 до 68 (в среднем около 57).
ES4009
ASSESSMENT OF KARST GROUNDWATER VULNERABILITY TO CONTAMINATION AS A TOOL FOR DELINEATION OF SOURCE PROTECTION ZONES: A CASE STUDY IN THE CRIMEAN MOUNTAINS
Аннотация
The assessment of groundwater vulnerability to contamination provides a hydrogeological basis for the designation of protection zones for drinking water sources. This paper presents a case study from the Crimean Mountains where karst groundwater plays a primary role in water supply. Groundwater vulnerability assessment has been carried out for two large karst springs: the Ayan and Krasnopeshcherny. For this purpose, a method adapted to the conditions of karst water formation in the region, called the Mountain-Crimean method, was used. The resulting source vulnerability maps of selected test sites demonstrate both similarities and differences. The common feature is the area predominance of the moderate vulnerability class, with a minor share of the low vulnerability class. However, the vulnerability classes on the two catchments have different placement patterns, as does the presence or absence of a high vulnerability class. The catchment area of the Krasnopeshcherny spring appeared to be more sensitive to pollution than the Ayan spring. The main reason is the hydrodynamic conditions of the deep parts of the karst aquifers drained by the springs. The karst aquifer of the Krasnopeshcherny spring has a much higher groundwater flow dynamic than that of the Ayan spring. The study closes by proposing a scheme of transition from vulnerability map to sanitary protection zones for karst water intakes in accordance with the regulatory standards of the Russian Federation.
ES4010
MERIDIONAL OCEANIC AND ATMOSPHERIC HEAT FLUXES AT THE ENTRANCE TO THE ATLANTIC SECTOR OF THE ARCTIC: VERIFICATION OF CMIP6 MODELS AND CLIMATE PROJECTIONS BASED ON THE SELECTED SUB-ENSEMBLES
Аннотация
Poleward transports of oceanic and atmospheric heat play an essential role in the Arctic climate system, and their variations in the future will strongly shape the climate of the Arctic. The main aim of this study is to evaluate the performance of the Coupled Model Intercomparison Project phase 6 (CMIP6) models in the historical experiment in simulating the meridional heat fluxes into the Atlantic sector of the Arctic. The secondary objective is to estimate the meridional oceanic and atmospheric heat fluxes up to the end of the 21st century using the best sub-ensembles of the CMIP6 models. According to our results, the CMIP6 models poorly reproduce the interannual variability of the heat fluxes in their historical simulations, and the multi-model ensemble mean values are systematically lower than the mean values derived from the Ocean ReAnalysis System 4 (ORAS4) and European Centre for Medium-Range Weather Forecasts Reanalysis version 5 (ERA5) reanalyses. Climate projections based on the selected CMIP6 models indicate that the future Arctic climate will be characterized by the significantly increased oceanic heat transport at the entrance to the Atlantic sector of the Arctic relative to the period 1958–2014. In contrast, the atmospheric heat and moisture transport will not have dramatic differences in the projected Arctic climate relative to the period 1958–2014. Based on the results obtained, we emphasize that any interpretation of future climate simulations should be done with caution.
ES4007
LOW-MAGNITUDE SEISMICITY OF THE CONTINENT-OCEAN TRANSITION ZONE IN THE EURASIAN ARCTIC
Аннотация
A significant increase in the number of seismic stations occurred in the Eurasian Arctic during the late 20th to early 21st century, which led to a decrease in the minimum magnitude of earthquake registration for some Arctic regions. One of the areas that have been until recently poorly studied in terms of low-magnitude seismicity includes the continent-ocean transition zone in the northern Eurasian shelf. An analysis of the monitoring performed using the seismic stations in operation in the Franz Josef Land and Severnaya Zemlya archipelagos complemented with data from the seismic stations on the Svalbard archipelago for the period from December 2011 to November 2020 made it possible to study the space-time patterns in the low magnitude seismicity at the continent-ocean transition zone. The most active features are the Franz Victoria and St. Anna grabens, and the Bely and Victoria High.
ES4011
MONITORING LAND COVER DYNAMICS AND FOREST DEGRADATION IN SOUTH SUMATRA PEATLANDS FROM 2015 TO 2023 BY REMOTE SENSING APPLICATION
Аннотация
Most Peat Hydrological Units (PHU) in South Sumatra, Indonesia, have been threatened by degradation from climate changes, human activities, and environmental factors. This study mapped land cover using Random Forest Classification and identified forest degradation using NDFI (Normalized Difference Forest Index) change analysis in several PHUs of the South Sumatra peatland from 2015 to 2023. We combined Sentinel-1, Sentinel-2, and Landsat-8 data for the land cover classification. Meanwhile, we utilized Landsat-8 to identify forest degradation. Our findings indicate that tree cover significantly decreased in 2015, 2019, and 2023, coinciding with severe drought conditions driven by El Niño events. A significant decrease in forest cover in 2019 was suggested by low tree cover, up to 47.1% of the total area of 1.054 million ha. Therefore, grassland and bare/sparse vegetation had more significant coverage percentages, reaching 22.89% and 11.40%, respectively, in 2019. Deforestation varied but generally decreased from 2015 to 2023, according to the analysis of NDFI changes. Vegetation regrowth increased notably from 2016 to 2020 and remained relatively stable afterward. In addition, forest disturbance decreased from 2015 to 2020 but slightly increased in the last few years. Although two PHUs have encountered more severe degradation, their peatland ecosystems included inside them have distinct characteristics. Specifically, the PHU of Sungai Saleh – Sungai Sugihan encompasses cultivated areas, whereas the PHU of Sungai Sugihan – Sungai Lumpur comprises protected areas. These findings highlight the need for restoration and sustainable land management to prevent further degradation
ES4012
СРАВНИТЕЛЬНОЕ ВЛИЯНИЕ ГИДРОМЕТЕОРОЛОГИЧЕСКИХ ПРОЦЕССОВ НА МЕЖГОДОВУЮ ИЗМЕНЧИВОСТЬ СЕЗОННЫХ КОЛЕБАНИЙ УРОВНЯ БАЛТИЙСКОГО МОРЯ
Аннотация
С помощью продолжительных среднесуточных мареографных наблюдений за уровнем моря, спутниковых альтиметрических измерений и данных реанализов метеорологических и гидрофизических полей исследуются особенности и физические механизмы межгодовой изменчивости сезонных колебаний уровня Балтийского моря. Показано, что за период 1889–2022 гг. в Стокгольме в межгодовых изменениях амплитуд гармоник Sa, Ssa, Sta, Sqa не отмечаются статистически значимые линейные тренды, но наблюдаются долгопериодные циклы с временными масштабами от 20–35 до 55 лет и очень значительными изменениями амплитуд от 0,5–1,0 до 25–27 сантиметров. В последние десятилетия у гармоник Sa, Ssa, Sta наблюдается заметное уменьшение амплитуд и дисперсии колебаний. Результаты взаимного корреляционного и множественного регрессионного анализов аномалий сезонных колебаний уровня моря и различных гидрометеорологических процессов свидетельствуют, что самый большой вклад в межгодовую изменчивость сезонных колебаний уровня моря оказывают изменения касательного трения ветра. Вторыми по значимости процессами являются изменения атмосферного давления над морем и водообмена между Балтийским и Северным морями. Самое незначительное воздействие на межгодовую изменчивость характеристик сезонных колебаний уровня моря оказывают изменения составляющих пресного баланса и плотности воды
ES4013
МОДЕЛИРОВАНИЕ ПЕРЕНОСА И НАКОПЛЕНИЯ ВЗВЕШЕННЫХ ВЕЩЕСТВ В УСЛОВИЯХ МАЛОВОДЬЯ И НАГОННЫХ ЯВЛЕНИЙ В УСТЬЕВОЙ ОБЛАСТИ Р. ДОН
Аннотация
Предложен подход к совместному применению модели, реализованной в программном комплексе HEC-RAS, и балансовой модели для описания переноса и трансформации взвешенных веществ в речной дельте. В устьевой области реки выделяются гидрологические районы: русловые районы, пойменные районы, затапливаемые при высоких паводках и штормовых нагонах со стороны моря, и районы авандельты. Для гидрологических районов строится динамическая модель баланса воды и веществ, переносимых водным потоком. Вводится параметризация процессов осаждения взвешенных веществ и их взмучивания в зависимости от скорости движения воды и размера частиц. Рассматривается три градации взвеси по размерам: пелитовая фракция (глина), алевритовая фракция (ил) и мелкий песок. Акцент делается на оценке влияния морских штормовых нагонов на перенос взвешенных веществ в речную дельту и их осаждение. Для описания потоков воды между районами, скоростей ее движения, динамики ее уровня и процессов затопления поймы применяется детальная модель на базе программного комплекса HEC-RAS, адаптированная к условиям устьевой области р. Дон. Выполнены расчеты переноса и накопления взвешенных веществ в устьевой области Дона для двух вариантов гидрологических условий – с нагоном воды со стороны моря и без него. Рассмотрена пространственно-временная изменчивость концентрации и гранулометрического состава взвешенных наносов в зависимости от гидрологических условий. Показано, что в отсутствие нагонных явлений при небольших расходах воды взвешенные вещества в основном осаждаются в авандельте за пределами морского края дельты, а в период нагона насыщают воду и на этапе подъема ее уровня поступают в дельту, частично осаждаясь в рукавах и в пойменных районах. При этом на этапе спада уровня воды из русловых районов они выносятся за морской край дельты, а в пойменных в основном остаются. Для условий маловодья при наблюдаемой частоте нагонных явлений и при отсутствии паводков устьевая область Дона задерживает в среднем 20% взвешенных веществ, поступающих со стоком р. Дон.
ES4014