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1.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

2.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

3.
钱迈 《海洋学研究》2010,28(2):36-44
我国的《领海及毗连区法》第2条规定:"领海基线向陆地一侧的水域为中华人民共和国的内水"。我国的《海域使用管理法》第2条规定:"本法所称内水,是指中华人民共和国领海基线向陆地一侧至海岸线的海域"。"两法"对"内水"的定义有水域和海域之分,因此容易引起解读上的分歧或执法上的模糊。分歧之一是,根据《海域使用管理法》,从领海基线向陆地一侧至海岸线部分,是否包括河口、海湾、滩涂等"内水";分歧之二是,根据《领海及毗连区法》,是否认定一部分"内水"即内海是由直线基线法所致。为什么"两法"对"内水"有水域和海域两种不同的定义?其一,"两法"针对的客体不同,《领海及毗连区法》针对的客体是国际或国外,该法的主体是国家主权;《海域使用管理法》针对的客体是国内海域,该法的主体是国内海域的使用管理。《联合国海洋法公约》(以下称《公约》)规定"领海基线向陆一面的水域构成国家‘内水’的一部分",那么另一部分"内水"就是正常基线向陆一侧的水域,包括江、河、海湾等,它完全置于国家领土主权之下。其二,用专业术语上的海岸线替代《海域使用管理法》中的海岸线会出现矛盾。专业术语上同指水陆分界线的有海岸线和"干出线"两种。前者是涨潮时离岸最近的线,后者是退潮时离岸最远的线,依据《公约》规定:"测算领海宽度的正常基线是沿海国官方承认的大比例尺海图所标明的沿岸低潮线,即退潮时海水离岸最远的那条线",所以低潮线更加符合《公约》和《海域使用管理法》中海岸线的定义,怎样理解海岸线才不会出现矛盾呢?本文认为,完全意义上的海岸线是大潮高潮线与低潮线之间的一条带状面,这个面有时被水淹没,有时出露,且宽窄不等,陡缓不一。当解读了《公约》的有关条款后,就不难理解领海基线向陆地一侧至海岸线的水域中有盐度为0.05~30和30~36范围的"内水"存在,盐度范围为0.05~30的"内水"是指按正常基线法划定领海基线而出现的"内水",包括水域和海域;盐度范围为30~36的"内水"是指按正常基线与按直线基线法划定的领海基线之间出现的"内水",即内海。它们在法律层面上有主从之分,不能混淆。  相似文献   

4.
采用实测资料分析、潮浪水槽试验、定床模型试验以及已建桥梁对涌潮影响的现场观测等手段,研究了钱塘江下游尖山河段建桥对涌潮景观的影响。研究结果表明,钱塘江河口的喇叭形河湾和庞大的水下沙坎使潮波能量积聚、潮差增大,水深急剧变浅、潮波剧烈变形是形成钱塘江涌潮的主要原因。影响涌潮的主要因素是潮汐、江道地形和治江围涂工程,而建桥不会影响涌潮产生的条件,但由于桥墩的阻水作用,对桥上游500 m范围内的涌潮形态有所影响;当采用合理的桥台设计方案,即阻水面积较小时,对上游涌潮高度的影响仅3 cm左右,故不会影响涌潮的景观。  相似文献   

5.
The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared.  相似文献   

6.
Backstripping of four marine wells on the northern margin of the Alboran Basin reveals a tectonic subsidence history that varies laterally along the margin from east to west. The well on the eastern margin (AndA1) records a fairly steady, continuous subsidence for most of its history, whereas wells on the western margin (AndG1 and AlbA1) show two distinct phases in their subsidence curves. The form of the subsidence curve for DSDP well 121 reflects its position on a structural high. Beta values for the tectonic subsidence curves range between 1.3 and 1.6.  相似文献   

7.
With the very extensive coastline in the north and northeast and the relatively shorter coastlines in the south, cheniers in the USSR can occur in a great variety of climatological conditions ranging from subarctic to subtropical. Cheniers in the USSR have been studied since approximately 1900, the investigations being mainly concerned with the palaeogeographical aspects. Since the 1960's, investigations have focussed on contemporary morphodynamics. Chenier formation appears to depend largely on the relative influence that marine and fluvial factors have on the formation of marginal deltaic plains. Research in this field is briefly reviewed.  相似文献   

8.
The influence of high vertical velocity gradients in the Black Sea Rim Current on the intensity of the vertical turbulent exchange is demonstrated on the basis of numerical modeling based on CTD data. The vertical turbulent exchange is confirmed by the anomalous distribution of the hydrochemical parameters in the redox layer. A system of equations for the kinetic energy of the turbulence and dissipation rate (k-? model) is used for the calculation of the coefficient of the vertical turbulent viscosity (diffusivity).  相似文献   

9.
An electronic databank on the seismostratigraphic units based on seismic studies in the northeastern Indian Ocean is created and schematics of the sediment thickness distribution over its area are compiled. For each unit, the interface boundaries are dated, the matter composition is identified, and the sedimentation rates are estimated. An integrated map of the total thickness of the sediments and rates of their sedimentation are constructed. The lower limit of the parameters of the sedimentation process for the sedimentary layers after their compaction caused by the weight of the overlying layers is characterized.  相似文献   

10.
An interactive three-dimensional chemistry-climate model combining models of the gas composition and general circulation of the lower and middle atmosphere is used to study the impact of changes in extra-atmospheric solar radiative fluxes induced by solar activity on the stratospheric heating and subsequent temperature and ozone variations in the stratosphere and troposphere. The results have shown that a change in the atmospheric radiative heating resulting from variations in solar activity has a direct effect on the temperature and circulation of the atmosphere. Atmospheric temperature variations affect the rates of temperature-dependent chemical reactions, and this is considered the first type of indirect impact of solar activity on the atmospheric gas composition. On the other hand, as a result of the variation in atmospheric heating, its circulation changes, thus affecting the transport of minor gases into the atmosphere. This effect is considered the second type of indirect impact of solar activity on atmospheric gases. The results of our calculations have shown that both types of indirect impact of the variation in solar activity on the atmospheric gas composition are comparable in order of magnitude to the direct impact of solar activity on atmospheric gases.  相似文献   

11.
Krasheninnikova  S. B.  Demidov  A. N.  Ivanov  A. A. 《Oceanology》2021,61(2):151-158
Oceanology - In this study, we estimated the transport and potential temperature of the Antarctic Bottom Water (AABW) and its variability on intra-annual, interannual, and decadal scales based on...  相似文献   

12.
It is known that by the general ‘geostrategy’ for the oceans we mean the behaviour of countries of the world in defending their own vital economic interests as projected on different oceans. The means for protecting national interests can be economic, political, diplomatic or military. This paper dwells in particular on these last aspects, offering in the first part some useful reflections on the analysis of regional seas. The second part gives elements for the understanding of the complex Mediterranean situation where the East-West confrontation is accentuated by widespread economic, political, ideological and ethnic contrasts between coastal states. For these reasons this sea can be defined as one of the most unstable and belligerent regions in the world.  相似文献   

13.
Three mathematical models are considered: a two-dimensional model for calculating the concentration fields of the ecosystem components on the shelf of the Republic of Guinea, a pointwise model for the annual variation of the components, and a two predators-prey model. These models are used to study the effect of hydrodynamic conditions on the state of the shelf ecosystem and for research into the causes which distort the balance between marketable and unmarketable fish.Translated by Mikhail M. Trufanov.  相似文献   

14.
Estimates of the characteristics of the horizontal turbulent exchange (coefficients of horizontal exchange, scales of deviations of the velocity of geostrophic currents from the background flows, and horizontal scales of perturbations) in the upper ocean layer were obtained on the basis of the data of expeditions held in 1978 and 1980 in the northwestern part of the Pacific Ocean. It is shown that the characteristics of the horizontal turbulent exchange strongly depend on the structure of the background flows, and one of the causes of their variability is related to tropical cyclones. A tendency to a decrease (to different degrees) of the turbulent coefficients in the wake of a tropical cyclone is noted.  相似文献   

15.
The model numerical experiments on estimating the accuracy of two methods for solving the problem of Kalman smoothing, both iteration and precise, are described on the basis of a simple equation for the passive admixture transport. Some quantitative estimations are given.Translated by Mikhail M. Trufanov.  相似文献   

16.
This paper focuses on the impact of periodic internal waves on the oxygen/hydrogen sulphide co-existence zone in the open Black Sea. The numerical model is based on a set of transport/diffusion equations governing the evolution of oxygen/hydrogen sulphide concentrations and considering the reaction between them. The wave velocity field is determined by solving a spectrum problem for preinertial period internal waves, using the characteristic vertical density profile for summertime. Via analysis of the model data, the influence of wave characteristics on the parameters of the O2/H2S co-existence zone has been assessed.Translated by Vladimir A. Puchkin.  相似文献   

17.
Several schemes of turbulent mixing in the upper ocean are considered, including a modified scheme based on the modified Monin-Obukhov similarity theory. The schemes have been used for the calculation of the evolution of the upper ocean. The results are compared with the data of automated buoys. It is shown that the scheme based on the similarity theory gives a result not worse than the commonly used ones and has several advantages, which makes it the most appropriate for including in the ocean circulation models and climate models.  相似文献   

18.
Mesoscale inhomogeneities in the fields of wind, temperature, and ozone concentrations have been studied on the basis of aircraft measurements performed within the international EUPLEX and RECONCILE projects in the northern polar region in the presence of the circumpolar vortex. Data have been obtained on the structure of turbulence inside and outside the circumpolar vortex. The zones of enhanced turbulence have been studied. The spectrum of coherence between ozone and wind velocity are found to have high values.  相似文献   

19.
Within the framework of the nonlinear theory of one-dimensional long waves, we performed the numerical analysis of the dependence of the intensity of tsunami on the shelf of the South Coast of Crimea on the location of the epicentre of underwater earthquakes near the continental slope of the basin. The calculations were carried out for the parameters of the model corresponding to the Yalta tsunami of September 12, 1927. It is shown that, for the same magnitude of the earthquake, the smaller the distance from its epicentre to the coastal line, the lower tsunami waves in the coastal zone and the smaller their vertical run-up. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

20.
本文基于南大洋环流研究最新资料,从资料来源、动力模式以及有待解决的问题几个方面较详细地阐述南大洋环流动力学研究动态。  相似文献   

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