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1.
We study the space-and-time variability of the concentrations of 27 microelements (Sc, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Mo, Ag, Cd, Sn, Se, Sb, Ba, La, Ce, Sm, Eu, Tb, Hf, Hg, Pb, Au, Th, and U) and Sr in the sea, river, and waste waters of the South Coast of Crimea in 2002–2007. Parallel with the data about elements studied earlier, we present, for the first time, the data of investigations of the contents of rareearth elements (Lu, Nd and Yb) whose concentrations in the major part of the analyzed samples of seawater were lower than the limit of their quantitative determination. We present the ranges of the concentrations of elements and perform their comparison with the data of the previous period of monitoring.  相似文献   

2.
Over the next 5–10 years, the WOCE hydrographic program will generate reliable hydrographic data for the world oceans. The resultant conductivity salinity, temperature, and pressure data will generate calculated densities that will be used to examine mixing along constant density surfaces. Changes in the composition of deep waters due to the breakdown of plant material can effect the calculated densities at a given conductivity salinity. The increases in SiO2, nitrate, alkalinity, and TCO2 (or pH) can change the density of seawater as well as the conductivity. For studies of the salinity and density fields over small spatial scales, these changes will be small, but for large scale and ocean to ocean studies the differences can be significant. The density calculations based on the salinity determined from conductivity need to be adjusted for the offsets due to changes in the composition of seawater. This report describes how this correction should be made using existing information.  相似文献   

3.
The currents in the Drake Passage are studied from the ADCP and CTD data acquired in a section across the Drake Passage in October-November of 2011 and from the satellite altimeter data. A complicated pattern of currents including eight jets of the Antarctic Circumpolar Current (ACC) and a system of slope and abyssal currents was found. The most interesting result is the discovery of several cyclonic and anticyclonic mesoscale eddies confined to the abyss. Some reasons explaining the generation of such eddies by the meandering of the ACC jets in the upper ocean layer are presented.  相似文献   

4.
Baranov  B. V.  Tsukanov  N. V.  Gaedicke  Ch.  Freitag  R.  Dozorova  K. A. 《Oceanology》2022,62(4):528-539
Oceanology - The specific morphology of the inner and outer slopes of the eastern Kuril–Kamchatka Trench were revealed based on joint study of bathymetry and seismic profiles obtained in two...  相似文献   

5.
The aim of the work is to check the hypothesis that quasiperiodic oscillations of meridional heat transport intensified by a positive feedback existing in the ocean–atmosphere system in subtropical regions is one of the principal factors governing the decadal variability of various hydrophysical fields in the North Atlantic. We use a simple three-box model of the North Atlantic with one lower and two upper boxes and meridional circulation for typical parameters of the ocean–atmosphere system. It is assumed that the decadal anomalies of sea-level pressure are proportional to the anomalies of sea-surface temperature. The deduced system of ordinary differential equations for the temperature of the upper two boxes with quadratic nonlinearity and the behavior of the solution in the vicinity of the stationary point are analyzed by using standard procedures for the investigation of linearized equations for small perturbations. It is shown that, for typical parameters of the ocean–atmosphere system, oscillating solutions for the sea-surface temperature with periods of 10–20yr can be realized even without taking salinity into account.  相似文献   

6.
Izvestiya, Atmospheric and Oceanic Physics - The Arctic stratosphere winter season of 2020–2021 was characterized by a weakened stratospheric polar vortex as a result of a major sudden...  相似文献   

7.
A short survey prepared by the Russian Commission on Atmospheric Radiation contains the most significant results of works in the field of atmospheric-radiation studies performed in 2007–2010. It is part of the Russian National Report on Meteorology and Atmospheric Sciences prepared for the International Association on Meteorology and Atmospheric Sciences (IAMAS). During this period, the Russian Commission on Atmospheric Radiation, jointly with concerned departments and organizations, ran the conference “Physics and Education,” dedicated to the 75th anniversary of the Department of Physics at St. Petersburg State University (2007); the International Symposium of CIS Countries “Atmospheric Radiation and Dynamics” (2009); and the 5th International Conference “Atmospheric Physics, Climate, and Environment” (2010). At the conferences, central problems in modern atmosphere physics were discussed: radiative transfer and atmospheric optics; greenhouse gases, clouds, and aerosols; remote methods of measurements; and new measurement data. This survey presents five directions covering the whole spectrum of investigations performed in the field of atmospheric radiation.  相似文献   

8.
A short survey prepared by the Russian Commission on Atmospheric Radiation contains the most significant results of work in the field of atmospheric-radiation studies performed in 2011–2014. It is part of the Russian National Report on Meteorology and Atmospheric Sciences prepared for the International Association on Meteorology and Atmospheric Sciences (IAMAS)1. During this period, the Russian Commission on Atmospheric Radiation, jointly with the concerned departments and organizations, organized two International Symposiums on Radiation and Dynamics (ISARD-2011 and ISARD-2013). At these conferences, the central problems in modern atmospheric physics were discussed: radiative transfer (RT) and atmospheric optics; greenhouse gases, clouds, and aerosols; remote methods of measurements; and new measurement data. This survey presents six directions covering the whole spectrum of investigations performed in the field of atmospheric radiation.  相似文献   

9.
《Marine Chemistry》2001,73(2):113-124
Dissolved boron in seawater occurs mainly in the form of boric acid (B(OH)3) and borate (B(OH)4−). While the equilibrium properties of the dissociation of boric acid have been studied in detail, very little work has focused on the kinetics of the boric acid–borate equilibrium in seawater. Here, we present a theoretical study of the relaxation of the seawater borate–carbonate system towards equilibrium using the experimental data of Mallo et al. [Nouv. J. Chim. 8 (1984) 373] and Waton et al. [J. Phys. Chem. 88 (1984) 3301]. The reaction rate constants are two to four orders of magnitude smaller than typical rate constants of diffusion-controlled reactions of other acid–base equilibria. This is presumably due to the substantial structural change that is involved in the conversion from planar B(OH)3 to tetrahedral B(OH)4. The time required to establish the boric acid–borate equilibrium in seawater is calculated to be ∼95μs at temperature T=25°C and salinity S=35. Considering stable boron isotopes 11B and 10B, the isotopic equilibration time is ∼125 μs. As a result, kinetic isotope effects during coprecipitation of boron in calcium carbonate are unlikely and therefore do not affect the use of stable boron isotopes as a paleo-pH recorder.  相似文献   

10.
The horizontal structure of the jets of the Antarctic Circumpolar Current (ACC) is analyzed on the basis of CTD- and LADCP- sounding performed during a hydrophysical survey with a 10-mile spatial resolution in the central part of the Drake Passage in October–November of 2008. According to the modern multijet classification of the ACC, the survey area covered the zones of three jets of the South Polar Current (SPC), which is the middle branch of the ACC. The current jets revealed a fine horizontal thermohaline structure, which was manifested even in the case of the confluence of individual jets into a “superjet.”  相似文献   

11.
Within the framework of the integral model in isopycnic coordinates including the upper mixed layer, we study the rearrangement of temperature and salinity fields in the Dead Sea. It is forced by the variability of atmospheric factors and mass fluxes through the lateral boundaries of the basin, which are connected with the freshwater run-off to the sea and the outflow from the sea to the shallow south bay, where evaporator installations for salt extraction are located. Such factors as solar radiation, wind velocity, air temperature, and relative humidity are prescribed. Evaporation is calculated with the use of a bulk formula, whereas precipitation intensity and discharge through the lateral boundaries are determined as functions of the sea level obtained from observations. This model reflects the specific character of the Dead Sea and takes into account the effect of water salinity on its evaporation, salt concretion, and mechanical evaporation. Comparison with the data of observations shows that the proposed model fairly precisely describes the observed specific features of the thermohaline water structure in the meromictic (1992–1996) and holomictic (1996–2000) periods.  相似文献   

12.
Sea surface height anomalies observed by satellites in 1992–2010 are combined with monthly climatologies of temperature and salinity to estimate circulation in the southern Bering Sea. The estimated surface and deep currents are consistent with independent velocity observations by surface drifters and Argo floats parked at 1,000?m. Analysis reveals 1–3-Sv interannual transport variations of the major currents with typical intra-annual variability of 3–7?Sv. On the seasonal scale, the Alaskan Stream transport is well correlated with the Kamchatka (0.81), Near Strait (0.53) and the Bering Slope (0.37) currents. Lagged correlations reveal a gradual increase of the time the lags between the transports of the Alaskan Stream, the Bering Slope Current and the Kamchatka Current, supporting the concept that the Bering Sea basin is ventilated by the waters carried by the Alaskan Stream south of the Aleutian Arc and by the flow through the Near Strait. Correlations of the Bering Sea currents with the Bering Strait transport are dominated by the seasonal cycle. On the interannual time scale, significant negative correlations are diagnosed between the Near Strait transport and the Bering Slope and Alaskan Stream currents. Substantial correlations are also diagnosed between the eddy kinetic energy and Pacific Decadal Oscillation.  相似文献   

13.
The behavior of the vertical aerosol structure (profiles of the ratio of the coefficients of the backward total and molecular scattering) in the height interval 30–80 km is analyzed from the results of lidar observations in Kamchatka over the period from October 2007 through December 2009. The obtained data revealed a regular two-layer aerosol structure in this height range with the maxima of the ratio of the scattering coefficients in the upper stratosphere at heights 35–50 km and in the mesosphere at heights of 60–75 km, as well as a relation between seasonal variations in the aerosol stratification and the circumpolar vortex affecting dynamic processes in the atmosphere of midlatitudes. The procedure of including the aftereffect of the Hamamatsu-M8259-01 PEM, which influences the error in the calculation of the ratio of scattering coefficients, is described.  相似文献   

14.
A brief review of the results of investigations carried out by Russian scientists in the field of dynamic meteorology in 2007–2010 is presented. This review is based on the information prepared by the Commission on the Dynamic Meteorology of the National Geophysical Committee, Russian Academy of Sciences, and included in the general information report of the Section of Meteorology and Atmospheric Sciences at the XXV General Assembly of the International Union of Geodesy and Geophysics.  相似文献   

15.
Mikhailova  N. V.  Bayankina  T. M.  Sizov  A. A. 《Oceanology》2021,61(4):443-449
Oceanology - The paper examines the influence of the main mode of interannual variability of the North Atlantic climate system—the North Atlantic Oscillation (NAO)—on the hydrophysical...  相似文献   

16.
In December–January of 2010 the spatial distribution of the phytoplankton production characteristics was studied along transects in the vicinity of the Greenwich meridian (I) and in the Drake Passage (II). On transect I, the surface chlorophyll a concentration and primary production varied from 0.11 up to 3.57 mg/m3 and from 4.38 up to 37.47 mgC/m3 per day, respectively. The chlorophyll a in the photosynthetic layer and the integrated primary production varied from 10.7 up to 66.1 mg/m2 and from 83 to 646 mgC/m2 per day, respectively. On transect II in the surface layer, the chlorophyll a concentration changed within the range of 0.09–1.02 mg/m3 and the primary production ranged from 2.08 to 9.49 mgC/m3. The integrated values ranged from 6.32 to 38.29 mg/m2 and from 41 to 221 mgC/m2 per day, respectively. The moderate means of themaximum quantum yield (F v/F m) on transects I and II (0.41 and 0.35, respectively) testify to the low activity of the phytoplankton’s photosynthetic apparatus. The studied water areas in the Southern Ocean differed both in the phytoplankton biomass expressed in the chlorophyll a concentration values and in the conditions of the primary production formation.  相似文献   

17.
Izvestiya, Atmospheric and Oceanic Physics - In early October 2011, two surface buoys were deployed off Peter the Great Bay in the Sea of Japan. They drifted in that area first, then crossed the...  相似文献   

18.
Terskii  P. N.  Panchenko  E. D.  Gorin  S. L.  Agafonova  S. A.  Vasilenko  A. N.  Kulikova  Z. M.  Popryadukhin  A. A.  Alabyan  A. M. 《Oceanology》2021,61(6):1076-1078
Oceanology - Winter field campaigns conducted by the Department of Hydrology of the Moscow State University Geographical Faculty undertaken during winter periods of 2017–2020 are introduced....  相似文献   

19.
The abundance, biomasses, and population structure of the ctenophore Mnemiopsis leidyi were monitored in the coastal waters of the northern part of the Black Sea (Sevastopol Bay and the adjacent continental shelf regions) in 2004–2008. The abundance and species composition of the comb jelly’s food in the sea were obtained along with experimental data on the digestion time. Based upon these data, the feeding intensity of the ctenophore in situ was estimated. This information was used to calculate the predatory impact of the comb jelly population on certain groups of forage organisms and the forage zooplankton community as a whole. The predatory impact of the M. leidyi population on the bivalve veligers was the highest (up to 90% of the abundance a day) compared to the Copepoda and Cladocera (30% and 40%, respectively). In the summers of 2004–2008, the daily consumption rates of the zooplankton by the ctenophore population in the shelf zone and in the bay were similar to each other: up to 15% and 12% of the abundance a day, respectively. The highest pressure of the ctenophore upon the zooplankton was observed in 2004 and 2008, when M. leidyi was especially abundant in the plankton for a long time.  相似文献   

20.
The evolution of oil pollution in the Gulf of Mexico from April 20 to May 28, 2010, which resulted from the accident on the BP Deepwater Horizon oil platform that occurred on April 20, 2010, is reviewed. The development of the situation was traced on the basis of a joint analysis of optical and radar images (RIs), which proved to be very effective since the optical images made it possible to exclude the areas of calm on the RIs from consideration, and the RIs gave more complete information about dimensions of the areas covered with oil films indiscernible on optical images. It is shown that the mesoscale water dynamics is of prime importance in oil pollution transport in the gulf; therefore, almost all model predictions of a giant oil spill drift were not justified.  相似文献   

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