Fundamental and Applied Hydrophysics最新文献

{"title":"Analysis of mesoscale frontal zones of the Norwegian Sea based on satellite observations and reanalysis data in May 2011–2020","authors":"A. Konik, O. A. Atadzhanova, E. V. Sentyabov","doi":"10.59887/2073-6673.2024.17(1)-4","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-4","url":null,"abstract":"   The aim of this study is to compare the horizontal temperature gradients calculated based on satellite observations and reanalysis data in the area of mesoscale frontal zones’ surface manifestations, both for the entire Norwegian Sea and during the onset of pelagic fish spawning migrations in May from 2011 to 2020.   Using monthly average temperature data from MODIS/Aqua, GHRSST OSTIA, and CMEMS GLORYS12v1, the fields of monthly and decade-long horizontal gradients on the surface of the Norwegian Sea were derived. A comparison was made between the decade-long temperature gradient estimates and their mean climatic values. The majority of the data show surface manifestations of the main frontal zones in the Norwegian Sea. Validation of temperature fields in the area of the Iceland-Faroe Frontal Zone was conducted based on unique in situ observations. It was demonstrated that for the analysis of the frontal zones in the Norwegian Sea, using the temperature fields of GHRSST OSTIA is most preferable. The obtained physico-geographical characteristics of mesoscale frontal zones could be used to assess their relationship with pelagic fish migrations in the Norwegian Sea.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"102 36","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140678639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Method for determining seabed penetration depth in marine seismic exploration","authors":"A. I. Mashoshin, A. V. Tsvetkov","doi":"10.59887/2073-6673.2024.17(1)-8","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-8","url":null,"abstract":"   The paper introduces a straightforward method aimed at determining the depth of penetration into the seabed during marine seismic exploration through bottom sounding. This technique was developed to support the establishment of technical specifications for the components of an underwater robotic complex intended for seismic surveys beneath ice formations. These components include a suite of autonomous underwater vehicles (AUVs) outfitted with either geophones or short streamers equipped with hydrophone sensors, alongside high-precision positioning systems. The complex comprises an underwater docking station responsible for deploying AUVs to the designated work area, managing their operations, and towing low-frequency sound emitters. Moreover, it encompasses coastal infrastructure dedicated to the maintenance of AUVs and the support of the docking station. The developed method considers various factors including the pressure exerted by the sound emitter and the energy dissipation of the probing signal due to wave front expansion, signal transmission into and back from the ground, spatial damping during signal propagation in water and soil, and reflection from oil or gas-containing lenses. Illustrative examples demonstrate the computation of ground penetration depth in shallow and deep waters, contingent upon the pressure exerted by the sound emitter towed at a depth of 100 meters. It also assesses the method’s reliability by comparing the computed outcomes against existing experimental data.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"115 44","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140678408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Marine profiling lidars and their application for oceanological problems","authors":"V. A. Glukhov, Yu. A. Goldin","doi":"10.59887/2073-6673.2024.17(1)-9","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-9","url":null,"abstract":"   The review focuses on research conducted using profiling (radiometric) lidars. The paper presents the current state of lidar surveying equipment, methods for processing lidar data, and describes the problems of scientific and practical interest in oceanology that can be solved using lidar sensing. The review does not cover issues related to laser bathymetry, spectral (Raman) and spaceborne lidars, as they are separate specific fields. The main focus is on recent research in profiling lidar field. Summary tables of the technical characteristics of several of the most interesting airborne and shipborne lidars are provided. Their design features are discussed. Results from using lidars to determine near-surface hydrooptical characteristics, including employing polarization lidars and recently developed high-resolution spectral lidars, are presented. Findings from observing thin scattering layers across various aquatic regions are shown. The paper explores theoretical studies on lidar images of internal waves and experimental observations of internal waves in waters with different hydrooptical stratification. Lidars' application in addressing fisheries-related issues is examined. An overview of current development trends and future research directions is provided.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"119 29","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140678476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconstruction of the currents structure in the Kuibyshev Reservoir using satellite data and field measurements","authors":"I. A. Kapustin, A. Molkov, A. Ermoshkin, D. Dobrokhotova, O. Danilicheva, G. Leshchev","doi":"10.59887/2073-6673.2024.17(1)-5","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-5","url":null,"abstract":"   This paper is devoted to a series of the first field subsatellite experiments conducted in the waters of the Kuibyshev Reservoir (Kama estuary) in 2023. Simultaneously with ship-based measurements of current and wind fields, as well as chlorophyll-a concentration, two high-spatial-resolution satellite scanners surveyed the study area of the reservoir. From sequential images, current fields were reconstructed using the standard maximum cross-correlation (MCC) method, which were then compared with measurements from the Acoustic Doppler Current Profiler (ADCP). In certain parts of the water area, satisfactory agreement was obtained between the reconstructed currents and direct measurement current data. And in those parts of the water area where a significant discrepancy between the ADCP and MCC data was recorded, the possible reasons for the discrepancies were analyzed. Preliminary estimates of the parameters that have a significant impact on the possibility of reconstructing currents using the MCC method in inland eutrophicated water bodies have been made, and some limitations of the MCC method as a whole have been identified. Possible ways of further development of the method are analyzed.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"103 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140678853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Broadband noise signal source positioning method using flat linear antenna in Fresnel zone near ‘water-air’ boundary","authors":"A. D. Konson, A. A. Volkova","doi":"10.59887/2073-6673.2024.17(1)-7","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-7","url":null,"abstract":"   Ways of broadband noise signal reception using flat linear extended antenna in Fresnel zone near surface boundary enabling to determine direction, range to the source and depth of its immersion simultaneously with detection are considered. The effect emerging when signal source and receiver are located near «water-air» interface and two beams arrive from source to receiver (direct beam and beam reflected from the surface) is investigated. The supervisor of compensation of delays of signal arriving to M receivers of the antenna focuses receiving system in the point of the expected positioning of the source. In case of dual-beam signal it may result in emergence of two range focusing points in space. It is shown that focal spots may have high range spreading or practically merge depending on the relative positioning of the source and the receiver. Method of source submergence depth analysis at known ranges to two focal spots is offered for the first case. Method of consolidated signal processing which includes additional scanning of time delays in possible delays of signal between beams with uniform delay for all antenna elements is offered for the case when focal spots are not separated. It is demonstrated that when obtaining maximum signal power entered delay will be functionally connected with depth of immersion of the source that enables carrying out joint determining of direction, ranges and depths of submergence of the source in offered method. Moreover, it is demonstrated that method of consolidated processing enables to increase power of arriving signal up to 50 % in the point of maximum response as compared to conventional signal reception algorithm using flat linear antenna in Fresnel zone.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"112 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140678180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the barotropic tidal dynamics of the Kuril region","authors":"А. А. Rodionov, R. E. Vankevich, M. K. Klevannaya, N. E. Voltzinger","doi":"10.59887/2073-6673.2024.17(1)-2","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-2","url":null,"abstract":"   A 3D boundary-value problem for computation barotropic tidal dynamics is solved at Kuril region, including southern part of the Okhotsk Sea, the Kuril Straits and its continental slope. The model is realised in statement for the contravariant components of velocity vector of the Programmed Complex “Cardinal”. Modeling the tidal dynamics of the straits of the Kuril Сhain and its continental slope is of particular importance due to the high geostrategic prestige of the region. The exceptional complexity of the relief of the area containing dozens of underwater volcanoes requires solving the problem in a complete non-hydrostatic formulation; this necessitates a multiprocessor implementation of the model with a high grid resolution for model representativity. An efficient methods for tidal dynamic reproduction at the 2D vertical cross-cuts domain is described. A statement of boundary problem at vertical cross-cuts is considered both in non-hydrostatic formulation and hydrostatic approximation. The results of computation contain the field of level tidal currents generated by the dominant wave K1 and summary wave in the synodic period; results of comparison the bottom vertical velocity at submarine mountain and on sharp depth changes in the hydrostatic and non-hydrostatic statements, result related to structure vertical velocity at cross-cut, the frequency spectrum and energy of tidal currents.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"11 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140681341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial structure of the temporary variability of the Arctic seas surface temperature","authors":"V. Gorchakov, A. Dvornikov, S. M. Gordeeva, V. Ryabchenko, D. Sein","doi":"10.59887/2073-6673.2024.17(1)-3","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-3","url":null,"abstract":"   Interannual oscillations in the surface temperature of the Arctic Ocean and the North Atlantic with the southern boundary (instead “border”) at latitude 55° 25′ N between 1949 and 2007 are investigated based on the MPIOM (Max Planck Institute Ocean Model) solution. It is a free surface ocean model based on primitive equations in the Boussinesq and incompressibility approximations. High-resolution spectra were estimated via fast Fourier transform with a maximum resolution (Welch’s method). Factor analysis method, which makes it possible to identify areas with highly correlated oscillations and reduce the study of the characteristics in question to their analysis in local points, is used to minimize the significant amount of the initial information about monthly average sea surface temperature fields. Аnalysis of the main factors made it possible to identify 10 areas with quasi-synchronous variability of temperature anomalies by including the points correlated with relevant factors with correlation exceeding 0.6. Spectral structure compliance classification revealed that the areas of the Chukchi Sea, the Hudson Bay, the Irminger Sea, and the Labrador Sea have oscillation peak similarities for the periods of 5–6 years and 8–9 years. Central and western areas of the Norwegian Sea, the area affected by the North Atlantic Current, the eastern part of the Norwegian Sea, and some areas of the Kara Sea have similar spectral structure defined by the peaks at the 11-year and 6-year periods. The Baffin Bay with two main peaks at the 16-year and 5–6-year periods, and the central and the western parts of the Barents Sea, where oscillations are similar to the ones in the Chukchi Sea at short periods, and to the ones in the south-eastern part of the Barents Sea and in the eastern part of the Norwegian Sea at 7–8-year periods, stand out significantly. In some cases, spectrum peaks in different areas appear shifted and attenuated, so presumably the frequency characteristics of the temperature signal change as it moves across the water area.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"116 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140680801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of interaction of a vortex ring with a normally located flat target","authors":"K. Volkov, V. Emelyanov, I. Kapranov","doi":"10.59887/2073-6673.2024.17(1)-1","DOIUrl":"https://doi.org/10.59887/2073-6673.2024.17(1)-1","url":null,"abstract":"   The need to develop models and methods for calculating unsteady gas and fluid flows with concentrated vorticity is determined by the wide distribution of such flows in nature and technology. Numerical simulation of the formation of a vortex ring, its propagation and interaction with a flat target oriented normal to the direction of movement of the ring is considered. The construction of a model of a virtual generator of vortex rings and the choice of a set of parameters describing the generating pulse (pulse duration and its amplitude) are discussed. The computational domain consists of the internal region of the vortex ring generator and the external space region behind its outlet, in which the formation and movement of the vortex ring occurs. For numerical calculations, unsteady Navier–Stokes equations in an axisymmetric formulation are used, for discretization of which the finite volume method is applied. To simulate the flow generated by the movement of the piston in the tube, unsteady boundary conditions are used at the outlet of the generating tube, describing the distribution of mass flow rate over time. The distribution of pressure over the target and the change in the longitudinal force acting on the target over time, as well as the change in the characteristics of the vortex ring during its interaction with the target are given. The results of numerical calculations are compared with the data of a physical experiment. A qualitative pattern of the flow that occurs when a vortex ring approaches a wall is presented, and the key features of the flow and critical points that are formed during the interaction of the vortex ring with the wall are discussed.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":" 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140684813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lidar Research during the First Stage of the 89th Cruise of the R/V “Academic Mstislav Keldysh”","authors":"V. A. Glukhov, Yu. A. Goldin, O. V. Glitko, E. Aglova, D. Glukhovets, M. A. Rodionov","doi":"10.59887/2073-6673.2023.16(4)-9","DOIUrl":"https://doi.org/10.59887/2073-6673.2023.16(4)-9","url":null,"abstract":"A lidar survey of the western part of the Kara Sea was carried out in September 2022. The shipborne radiometric (profiling) lidar PLD-1 was used. The lidar optical unit was located on the 8th deck of the R/V ‘Akademik Mstislav Keldysh’ at an altitude of 15 m above the water surface. Lidar sounding was carried out at stations and underway. The vessel route passed through water areas characterized by a wide range of changes in hydrooptical characteristics. Lidar measurements were accompanied by synchronized measurements of hydrooptical and hydrological characteristics. These measurements were carried out using submersible instruments at stations and using a flow-through measuring complex along the ship's route. The hydrooptical characteristics vertical distribution uniformity in the upper ten-meter layer was controlled remotely using underway lidar data.Good agreement between the spatial distributions of the lidar echo signals parameters, of the hydrooptical and of the hydrological characteristics (coincidence of the locations of various distribution features, local maxima, minima and frontal zones) was demonstrated. A large volume of measurement data has been obtained, which allows for further statistical processing in order to find relationships between the parameters of lidar echo signals and hydrooptical characteristics recorded by contact methods.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"64 37","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139534757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Registration of Phytoplankton Fluorescence Using an Experimental Sounding Probe","authors":"O. B. Kudinov, M. E. Lee","doi":"10.59887/2073-6673.2023.16(4)-10","DOIUrl":"https://doi.org/10.59887/2073-6673.2023.16(4)-10","url":null,"abstract":"The main optical characteristics of phytoplankton and colored dissolved organic matter are described. The necessity of simultaneous registration of fluorescence of phytoplankton pigments and colored dissolved organic matter in seawater in situ is substantiated. Commercial recording devices, realizing registration of signals of phytoplankton fluorescence intensity in situ, are considered. This paper presents the developed experimental probing autonomous multichannel multichannel meter of fluorescence and light scattering in seawater (FR1). The paper presents the functional scheme of the developed meter, describes its main assemblies and principles of its operation. The developed meter allows quasi-simultaneous registration of a large set of parameters: excitation spectra of phytoplankton fluorescence, fluorescence intensity of phytoplankton pigments (chlorophyll-a, phycoerythrin, phycocyanin, β-carotene), as well as fluorescence intensity of colored dissolved organic matter and spectra of light scattering index at an angle of 90°. Registration of all these parameters is carried out from one measuring volume, where the same composition of suspended matter is located in the process of probing at each specific moment of time. The paper presents the results of approbation of the developed meter and suggests the direction of further research using it.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"67 40","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139534621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}