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1.
This paper analyses the global tendency of the sea level rise (SLR) and its long term influence on the sea level upstream drainage cascade based on the example of the level’s variation in the Vistula Lagoon of the Baltic Sea compared to the other lagoons and coastal regions of the southeastern part of the Baltic Sea. A steady positive trend in the water level variations was revealed; its magnitude varies significantly depending on the time period. In general, during the 100–150 year period, the rate of the SLR in the lagoons and coastal areas of the Baltic Sea (1.7–1.8 mm per year) is close to the SLR rate in the World Ocean. In the second half of the 20th century, the increased rate of the SLR in the lagoons and marine areas became stronger (up to 3.6 mm per year in the Vistula Lagoon and in 1959–2006 in the sea and exceeded the rate of global ocean SLR). It dramatically increased at the end of the last century both in the lagoons and in the sea (up to 10.0–15.0 mm per year). This is the response not only to the global climate warming but it is likely that it is also a response to the changes of the climate driving forces that influence the regimes of the local wind and precipitation in the catchment.  相似文献   

2.
1Introduction Besidestheprecipitationandriverdischarges,the watersinthePacificOceanandtheAtlanticOceanare thesourcesoftheArcticOceanwater.TheAtlantic waterenterstheArcticOceanviatheFramStraitand theBarentsSea.Foritsdenserfeatureduetohigh salinity,mostofitsinkstothenorthofSvaldbardand circulatesinallthedeepbasinsintheArcticOcean, formingthedeepandbottomwatersoftheArcticO- cean(Aagaardetal.,1985;Rudelsetal.,1999).The BeringStraitistheonlychannelforthePacificwater toflowintotheArcticOce…  相似文献   

3.
Data on the contents and compositions of the hydrocarbons (HCs)—aliphatic (AHCs) and polycyclic aromatic (PAHs)—are provided in comparison with the contents of the total organic carbon (Corg), the lipids in the particulates, and the Corg in bottom sediments. Particular attention has been paid to the distribution of the HCs in the water area of the Kravtsov oil field. It has been established that the concentrations of AHCs in the water are governed by the content of particulates, and the elevated AHC concentrations are confined to the coastal areas. In the water area of platform D-6, the sandy bottom sediments were notable for the great variability of the HC concentrations, both laterally and from year to year. In the summer of 2010, the content of AHCs averaged 40 μg/g (19% in the Corg), and that of PAHs, 23 ng/g. Natural seepage from the sediment mass is considered to be a source of HCs along with oil contamination.  相似文献   

4.
A. A. Maximov 《Oceanology》2006,46(2):185-191
The data on the bottom concentrations of dissolved oxygen in the eastern part of the Gulf of Finland obtained in 1923–1939 and in 1962–1989 were analyzed. No statistically reliable differences were found between the two periods studied. It was found that, during the 20th century, the fluctuations in the oxygen concentration were caused by the interannual variability of the winter severity and water salinity. A strong oxygen deficit in the summer was recorded after cold winters, when early freezing suppressed the vertical mixing, and/or in the years of a significant inflow of salt waters from the Baltic Sea with low oxygen contents. It is likely that the long-term dynamics of the oxygen concentration near the bottom in the open parts of the bay is determined by the large-scale variability of the hydrometeorological parameters.  相似文献   

5.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

6.
Izvestiya, Atmospheric and Oceanic Physics - The Great Andaman–Sumatra earthquake (GASE) on December 26, 2004, with magnitude Mw of 9.2, occurred in the Indian Ocean near the northwestern...  相似文献   

7.
近30年来莱州湾滨海湿地景观格局变化特征研究   总被引:1,自引:0,他引:1  
基于莱州湾滨海湿地特征以及野外实地观测数据,利用landsat遥感影像手段,揭示1990—2018年莱州湾滨海湿地景观格局变化特征,并结合景观指数分析莱州湾滨海湿地异质性.结果表明,1990—2018年间,莱州湾滨海湿地呈现人工滨海湿地面积增加而天然滨海湿地面积减少的趋势.截至2018年莱州湾滨海湿地面积总计1954 ...  相似文献   

8.
1 IntroductionTheBeringStrait, with them aximum depth lessthan 60 m , isthe uniquepassagebetween the ArcticOcean and the North Pacific Ocean, and links twoshelfseas:theBeringSeainthesouthandtheChukchiSea in the north. The background flow field oftheBering…  相似文献   

9.
The role of the small-size (SF; 0.1–0.5 mm) and large-size (LF; 0.5–20.0 mm) fractions in the biomass and abundance of mesozooplankton (0.1–20.0 mm) was assessed using the database of samples obtained during the cruises of RV Akvanavt in the northeastern Black Sea in November 2000 and October 2006. The mesozooplankton was collected by means of Juday nets (37/50, filtering gauze 160 μm) and Niskin bottles in two areas: (1) the shelf and continental slope (30–1480 m depth) and (2) the deep sea (depths of more than 1500 m). The plankton net was considerably less effective in collecting the SF of the mesozooplankton (by a factor of 30–36) than the Niskin bottles. When comparing the SF and LF, we estimated the abundance and biomass of the SF in the samples obtained with the Niskin bottles. The abundance of the SF in the deep-sea area was 2.5 times lower compared to the shelf and continental slope, and the LF abundance was 5.0 times lower in the same way. The abundance of the SF constituted 88% of the total mesozooplankton on the shelf and continental slope, and 78% in the deep-sea area. The biomass of the SF was higher as well on the shelf and continental slope. Meroplankton played a significant role in the SF zooplankton abundance (0.5 × 103 + 0.16 ind. m−3) in this area. The SF grazing impact was 10% of the total mesozooplankton grazing on the shelf and continental slope, and 17% in the deepsea area. Appendicularia and nauplii of copepods had the greatest contribution to the mesozooplankton grazing among the SF group.  相似文献   

10.
This paper presents an evaluation of the effectiveness of the regulatory regime in the management of oil pollution on Kenya's marine and coastal environment. The prospect of chronic oil pollution along the Kenyan coastline and the port of Mombasa is discussed. A review of the vulnerable marine and coastal resources, commonly used indicators of effectiveness in oil pollution management and the legislation governing oil pollution is given. The author concludes by emphasising that despite having the right legislation in place, there is need for the establishment of criteria and indicators necessary for evaluation of policy effectiveness.  相似文献   

11.
According to the results of the comparative study performed of the littoral sediments sampled in small inlets of Kandalaksha Bay (the White Sea in the Russian Arctic), the metals (Fe, Mn, Cu, Zn, Pb, Cr, and Li) occur mainly in a biogeochemical-stable mineral-incorporated form, which comprises 77–99% of the total metal content. The ratio of the liable form, which is easily extracted by a weak acid, is on average 3.2% for the total Fe, 2.0% for Mn, 1.7% for Cr, 5.6% for Pb, 5.8% for Zn, 6.5% for Cu, and is negligible for Li. The concentrations of the most studied trace metals are below the threshold level according to the environmental quality guidelines (the sediment analysis). The ratio of the metal forms evidences the natural origin of the elevated concentrations of both Zn and Cr in the sediments.  相似文献   

12.
Using the data of long-term simultaneous optical, biological, and hydrological observations (1980–1993), particular features of the horizontal distribution of the transparency and the total particulate matter content and the contents of its organic components (organic carbon and nitrogen and chlorophyll a) and their variability in the surface water layer (0–5m) over the northwestern shelf and the adjacent abyssal part of the Black Sea in the autumn season are considered. The detritus/phytoplankton ratio in the particulate organic matter and their relative contents in the total particulate matter are calculated. The distributions of the transparency and particulate matter content were found to be in good agreement and both depend on the water dynamics. It was established that, during the period of the abrupt growth in the Black Sea water turbidity (in the early 1990s), a significant decrease in the transparency and an increase in the particulate matter content caused by the production-destruction processes were observed only in the central and southern regions of the sea.  相似文献   

13.
The data for the present study were collected at 20 sampling stations in the Kara Sea along the transect from the Ob estuary to the deep sea St. Anna Trough in September 2007. Based on the hydrophysical features, the distribution of the Chl a, and the primary production, we distinguished six habitats: the river, estuary, inner and outer shelf, continental slope, and trough. The impact of the small-size (<0.5 mm) and large-size (>0.5 mm) fractions of the zooplankton on the phytoplankton’s organic carbon in the different regions of the Kara Sea was estimated. The ingestion rate was assessed using the analysis of the gut fluorescence content and the gut evacuation rate. The zooplankton grazed 1–2% of the phytoplankton biomass in the river and estuary; 3.5% over the shelf; and 6 and 10% in the regions of the trough and slope, respectively. The grazing impact of the small-sized zooplankton increased from the river zone to the deep regions (from 1 to 90%) along with their share in the total zooplankton abundance (from 18 to 95%). From 72 to 86% of the primary production was grazed over the shelf and slope. The primary production did not cover the feeding requirements of the zooplankton in the estuarine regions and St. Anna Trough in the autumn. In the estuarine regions, the major portion of the organic matter settles on the bottom due to the strong inflow of the allochthonous matter and the relatively low zooplankton grazing.  相似文献   

14.
A numerical experiment on the reproduction of the variability in the state of North Atlantic water in 1948–2007 with a spatial resolution of 0.25° has been performed using the global ocean model developed at Institute of Numerical Mathematics, Russian Academy of Sciences (INM RAS), and the Shirshov Institute of Oceanology (IO RAS) (the INM–IO model). The data on the state of the atmosphere, radiation fluxes, and bulk formulas of the CORE-II protocol are used as boundary conditions. Five successive 60-year calculation cycles have been performed in order to obtain the quasi-equilibrium state of a model ocean. For the last 20 years, the main elements of large-scale ocean circulation have been analyzed and compared with the WOA09 atlas data and the results of other models.  相似文献   

15.
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   

16.
The shelf zones of the Black Sea, Taman Bay, and the Sea of Azov are currently subjected to gross load related to the impact of invasive species, large-scale construction activities near the coast, intensive recreation activity, water pollution in large cities and ports, active navigation, unreasonable coastal arrangement, and dam construction. Another factor substantially affecting the composition of bottom sediments and, thus, the benthos environment is the terrigenous material carried by rivers in the course of catastrophic overflows. An example is the Kubansk flood in 2012, which significantly affected the sea coast near Novorossiysk, Gelendzhik, and Divnomorsk. The intensive onshore dumping results in the delivery of abundant allochthonous material, bottom silting causing changes in the dominants in the benthos associations, a decrease in the photic layer and the death of the phytobenthos, and also debris formation at the bottom. Debris can play the role of artificial reefs contributory for the formation of periphytic biocoenoses.  相似文献   

17.
On the basis of the data of the complex oceanographic experiment carried out in the course of the second Ukrainian Antarctic expedition in March 1998, we study the structure and kinematics of waters in the region of the archipelago of Argentine Islands. The regularities of thermohaline stratification of waters are discovered. We determine the most important environmental parameters premoting the variability of hydrophysical fields on time scales varying from several days up to a week, analyse the data of actual observations over the currents, and estimate the relative contribtions of diurnal and semidiurnal tidal waves to the total dispersion of hydrophysical parameters of the environment. The residual currents are filtered out. We propose a hypothesis about the mechanism of their formation. Various types of tidal currents are revealed and the directions of propagation of diurnal and semidiurnal tidal waves are determined. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

18.
生态因子在黄海绿潮生消过程中的作用   总被引:2,自引:2,他引:0  
白雨  赵亮  刘境舟 《海洋学报》2019,41(8):97-105
2008–2017年南黄海海域连续10 a发生绿潮,影响周边沿海城市养殖、旅游和航运安全等。研究绿潮生消过程及其影响因素对于理解黄海绿潮分布特征,开展绿潮灾害的预防与治理有重要意义。本文主要采用MODIS L1B数据,通过归一化植被指数提取绿潮信息。根据逐年绿潮覆盖面积的变化特征,将绿潮生消过程分为3个阶段:触发阶段、快速发展阶段、消衰阶段,分析了海表温度、降水和光照在绿潮生消过程中的作用。结果表明:在触发阶段,温度达到15°C后,有效降水可以刺激绿潮的触发,在降水后的半个月内可以通过MODIS影像发现绿潮。在快速发展阶段,绿潮所在位置海表面温度为16~21°C,适宜绿潮的快速生长;太阳短波辐射集中在250~280 W/m2范围内;降水量是影响绿潮生长规模的一个重要因素,降水量少时绿潮覆盖面积峰值明显较小,而出现绿潮覆盖面积最大值的2016年降水量也极高。在消衰阶段,海表温度上升至22~26°C,绿潮在卫星影像中消失时,平均海表温度超过26°C,最高温度可达27.48°C,较高的海表面温度是导致绿潮消亡的主要原因之一;太阳短波辐射集中在240~260 W/m2,略低于快速发展阶段光照范围;降水量在该阶段相对充足不再影响绿潮的生长。  相似文献   

19.
The results of a joint analysis of the synchronous-profile ensemble of density and current velocity measured using the autonomous moored Aqualog profiler at the Gelendzhik experimental site of the Shirshov Institute of Oceanology in 2013–2015 are presented. The distribution of probability density of current velocity by directions reveals the presence of two well-pronounced maxima in the southeastern and northwestern sectors at all depths of measurements, which confirms the bimodal direction of the currents in the study site. We consider in detail the vertical structure of the density stratification and the current velocity corresponding to the modes determined from the maximum of the probability density distribution of the current velocity by directions. The averaged profiles of the kinetic, potential, and total energies are given. The results of isopycnic averaging over the entire ensemble of profiles indicate that possible self-similarity exists in the dependence of the vertical distribution of density and kinetic energy.  相似文献   

20.
Seasonal variability of interannual fluctuations of the heat balance components of the upper quasi-homogeneous ocean layer (UQL) in the North Atlantic is analyzed by processing the reanalysis data set for the period of 1959–2011. It is shown that interannual variations in the components of the UQL heat budget are characterized by pronounced regional features in all seasons. In the tropics and subtropics, heat balance is quasistationary and is determined by the nonlocal processes, such as heat advection and horizontal mixing. In the subpolar latitudes, nonstationarity (in the spring) and heat fluxes at the UQL boundary (in the autumn and in the winter) are also important. A major role in the interannual variability of the UQL temperature in the vicinity of jet currents of the Gulf Stream type is played in all seasons by the fluctuations of horizontal heat advection. However, the contribution of interannual fluctuations of the individual components of the heat budget to variability of the UQL temperature varies considerably in different seasons. The interannual fluctuations of the local variation in the UQL temperature are characterized by the largest variability in the spring and the lowest one in the autumn. The greatest contribution of the variations in the horizontal heat advection to the change in the UQL temperature at the interannual scale is recorded in the winter, and the lowest one is in the summer. The contribution of the interannual variations in the heat fluxes at the UQL upper boundary to the variability of the UQL temperature is the highest in the summer and the lowest in the autumn. Fluctuations of the heat fluxes at the UQL lower boundary do not have a significant impact on the interannual variations in the UQL temperature for the whole water area. The exception is small areas in the region of the formation of the North Atlantic deep water in the autumn–winter period and in the vicinity of the Equatorial Counter Current in the spring–summer period.  相似文献   

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