Investigation of Frontal Zones in the Karkinitskii Bay

On the basis of the data from the databank of the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences and the data of regional marine hydrometeorological stations, we present the characteristics of the seasonal variability of temperature and salinity frontal zones and background gradients in waters of the Karkinitskii Bay. We determine the locations of the frontal zones, the values of their gradients, horizontal scales, repetition, connection with weather conditions, inflow, and direction of propagation of salt and freshened waters in the bay in different seasons of the year. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 30–42, July–August, 2005.     

Regularities of seasonal variations in the content and distribution of oxygen in waters of the Sevastopol Bay

We study the regularities of annual variations in the concentration of oxygen and the degree of saturation of waters in the Sevastopol Bay with oxygen in 1998–2009. The three-dimensional specific features of seasonal variations in the distribution of oxygen in waters of the Sevastopol Bay are revealed. Two periods can be separated in the annual course of the content of oxygen in the surface layers of waters in all parts of the bay: the period of supersaturation in March–September and the period of undersaturation in October–February. In the bottom layer of waters in all parts of the bay, we observe the undersaturation of waters with oxygen for the whole year.     

Preliminary results of the expedition of the marine hydrophysical institute of the ukrainian national academy of sciences on the R/V Éksperiment in the northwest part of the black sea in May 2007

In May 2007, the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences carried out an oceanographic expedition in the northwest sector of the Black Sea. This expedition originates a series of surveys scheduled for this region. It was realized within the framework of national and international projects, such as Climate, Ecoshelf, Stable Ecosystem, SESAM, ECOOP, and Oceanography. We present the data on the works carried out in this expedition and perform a brief analysis of the process of subduction of waters on the northwest shelf. It is shown that, despite the abnormally warm preceding autumn–winter period, the wellpronounced subduction of waters formed in the process of autumn–winter cooling was still observed over the drop of depth along the isopycnic surfaces σt = 14.0 and σt = 14.5–14.6 in May 2007. New data on the intensity of vertical turbulent exchange over the continental slope in the northwest part of the Black Sea are obtained.     

Features of hydrophysical and hydrochemical conditions in Blagopoluchiya Bay (Novaya Zemlya Archipelago)

The report presents the results of hydrophysical and hydrochemical studies in Blagopoluchiya Bay (Novaya Zemlya Archipelago) based on data of integrated expeditions of the Institute of Oceanology in the Kara Sea in 2007, 2013, and 2014. The main focus was the influence of the Ob and Yenisei rivers, as well as of the runoff of meltwaters from the coasts of the archipelago on the hydrochemical and hydrophysical structures of the bay waters. The features of water exchange between the bay and adjacent aquatic area are considered, along with the renewal mechanisms for deep waters in the bay (deeper than 100 m). The possible occurrence of stagnant effects in deep layers of the bay is evaluated.     

Analysis of state of the carbonate system of waters and variations of the content of organic carbon in bottom sediments of the Sevastopol bay in 1998–2005

On the basis of the experimental data accumulated in 1998–2005, we analyzed the space and time variations of the carbonate system of waters and the content of organic carbon in bottom sediments of the Sevastopol Bay. The intensity of gas exchange through the water-atmosphere interface was quantitatively estimated. It was shown that the partial pressure of carbon dioxide pCO₂ in waters of the bay became much higher for the period of observations. The maximum changes were observed in summer. They were especially pronounced for the bottom layer of waters. For the entire period of observations, the invasion of carbon dioxide CO₂ was predominant in the major part of the bay, and the content of organic carbon in the bottom sediments increased. The ability of waters in the bay to absorb CO₂ is explained by the synthesis of organic substances, which becomes possible due to the presence of the equivalent load of nutrients. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 57–67, March–April, 2008.     

Investigation of the mechanism of the long-term evolution of the carbon cycle in the ecosystem of the Sevastopol bay

We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.     

Modeling of Circulation and Propagation of Contaminating Impurities in the Balaklava Bay

The Princeton Ocean Model is adapted to the water area of the Balaklava Bay for the numerical analysis of circulation. The calculations are performed with the help of the diagnostic method by using the data of the hydrological survey carried out in the bay in August 1992. We study the structure of the surface and bottom currents in the analyzed period as well as the vertical circulation of waters and the circulation averaged over the depth. The obtained three-dimensional fields of currents are used for the numerical analysis of the process of propagation of passive contaminating impurities from the sources located on the coasts of the Balaklava Bay. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 49–61, May–June, 2005.     

Simulation of the Circulation and Space Structure of Thermohaline Fields in the Sevastopol Bay with Regard for the Actual External Data (Winter, 1997)

We discuss the results of the numerical experiment aimed at the simulation of the behavior of currents and transformations of the temperature and salt modes in the Sevastopol Bay in January–February 1997. In the numerical analysis, we use actual data on the velocity and direction of the wind, sea surface temperature, and the discharge of River Chernaya. It is shown that the circulation and structure of hydrological fields are mainly connected with the direction of the wind, its intensity, and variability in the course of time. Since the analyzed water area is shallow, the currents inside the bay undergo rapid transformations (less than for an hour after changes in the wind). At the same time, the transformations of the thermohaline fields are slower. Due to the inflow of fresh waters of River Chernaya and salt waters from the open sea through the strait, the structure of thermohaline fields formed in the bay is nonuniform (both in the vertical and horizontal directions). The distribution of salinity plays the main role in the formation of the vertical stratification, which is natural for the winter season. Due to the process of freshening of water, a quite high vertical salinity gradient is formed in the upper layer of the sea. As a result, the process of cooling does not lead to the appearance of convection and inversions of temperature are formed in the case where warmer waters are located in the bottom layers. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 60–76, March–April, 2005.     

Transformation of black-sea waters in the Sea of Marmara

The analysis is performed on the basis of comparison of the hydrological characteristics of prestrait regions of the Sea of Marmara. It is shown that, in summer, the Black-Sea waters are weakly mixed with the Mediterranean waters and the levels of salinity in the prestrait regions differ by 0.6–0.9‰. In winter, the indicated difference increases and the level of salinity near the entrance of Dardanelles reaches 29‰ and exceeds the level observed near the entrance of Bosporus by 5.5‰. In the analyzed regions, we observe local temperature maxima and minima near the interface of two water masses. This is explained by the presence of strong seasonal variations of temperature for the Black-Sea waters and their absence for the Mediterranean waters. The physical mechanisms responsible for the seasonal variations of the intensity of transformations of the Black-Sea waters are discussed. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 49–55, March–April, 2007.     

Methodical aspects of the application of acoustic Doppler current profilers in the Black Sea

For the first time, an acoustic Doppler current profiler (ADCP) produced by the RDI is used in the water area of the Black Sea in the lowered mode. This direction in the application of acoustic Doppler current profilers is now in the stage of development and verification of various procedures of measurements with subsequent data processing and enables one to get the distributions of current velocities down to depths of 1000–6000 m depending on the modification of the instrument. We describe the procedures of measurements performed with the help of the ADCP in the lowered mode in the course of an expedition and the stages of processing of the primary data based on the experience of application of similar acoustic current profilers at the Marine Hydrophysical Institute of the Ukrainian National Academy of Sciences accumulated in the 1980s. We generalize the experience of application of ADCP under the hydrological conditions of the Black Sea, propose the algorithms of data processing, present the profiles of absolute current velocity at several stations, compare these profiles with the geostrophic velocities, and determine the deep-water structure of the field of currents in a shelf-open-sea section made along 31.17°E. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 4, pp. 31–48, July–August, 2006.     

On the transformation of the chemical composition of the Volga River discharge waters at the Caspian shallows

The Volga River discharge consists of the waters transferred by fast currents through channels and the waters which are passing through the shallow areas of the delta overgrown by cane. Using the hydrochemical data, it is possible to track distribution of the waters modified by “biofilters” of macrophytes in the delta shallows starting from the external edge of the delta. The main distinctive features of these waters are the high content of dissolved oxygen, the abnormally high values of the pH, and the low content of dissolved inorganic carbon (both total and as CO₂). These waters extend in the shape of 1 to 3-km-wide strips at a distance of 20–40 km from the outer border of the delta. The analysis of the data obtained during the expeditions run by the Institute of Oceanology of the Russian Academy of Sciences in 2003–2009, along with archived and published data, show that such “modified” waters occur almost constantly along the outer edge of the Volga River delta.     

Climatic structure of the wind fields in the Black-Sea region

For the Black-Sea region, we perform the dynamic reanalysis of the data on atmospheric circulation for the period 1958–2001 by using the HadRM3P model with a space resolution of 25 km. We estimate the mean climatic atmospheric fields of vorticity and divergence of the wind velocity and study their space structure and seasonal variability. The climatic estimates of the annual course of vorticity of the wind velocity over the sea are presented. The obtained large annual average values of vorticity of the velocity reveal the predominant role played by the wind action in the generation not only of the seasonal variability but also of the mean cyclonic circulation of waters in the Black Sea.     

Oxygen Utilization and Organic Carbon Remineralization in the Upper Water Column of the Pacific Ocean

As a part of the JGOFS synthesis and modeling project, researchers have been working to synthesize the WOCE/JGOFS/DOE/NOAA global CO₂ survey data to better understand carbon cycling processes in the oceans. Working with international investigators we have compiled a Pacific Ocean data set with over 35,000 unique samples analyzed for at least two carbon species, oxygen, nutrients, chlorofluorocarbon (CFC) tracers, and hydrographic parameters. We use these data here to estimate in-situ oxygen utilization rates (OUR) and organic carbon remineralization rates within the upper water column of the Pacific Ocean. OURs are derived from the observed apparent oxygen utilization (AOU) and the water age estimates based on CFCs in the upper water and natural radiocarbon in deep waters. The rates are generally highest just below the euphotic zone and decrease with depth to values that are much lower and nearly constant in water deeper than 1200 m. OURs ranged from about 0.02–10 μmol kg⁻¹yr⁻¹ in the upper water masses from about 100–1000 m, and averaged = 0.10 μmol kg⁻¹yr⁻¹ in deep waters below 1200 m. The OUR data can be used to directly estimate organic carbon remineralization rates using the C:O Redfield ratio given in Anderson and Sarmiento (1994). When these rates are integrated we obtain an estimate of 5.3 ± 1 Pg C yr⁻¹ for the remineralization of organic carbon in the upper water column of the Pacific Ocean. This revised version was published online in July 2006 with corrections to the Cover Date.     

Seasonal variations of water system distribution and flow patterns in the southern sea area of Hokkaido,Japan

Hydrographic data and composite current velocity data (ADCP and GEK) were used to examine the seasonal variations of upper-ocean flow in the southern sea area of Hokkaido, which includes the “off-Doto” and “Hidaka Bay” areas separated by Cape Erimo. During the heating season (April–September), the outflow of the Tsugaru Warm Current (TWC) from the Tsugaru Strait first extends north-eastward, and then one branch of TWC turns to the west along the shelf slope after it approaches the Hidaka Shelf. The main flow of TWC evolves continuously, extending eastward as far as the area off Cape Erimo. In the late cooling season (January–March), part of the Oyashio enters Hidaka Bay along the shallower part of the shelf slope through the area off Cape Erimo, replacing almost all of the TWC water, and hence the TWC devolves. It is suggested that the bottom-controlled barotropic flow of the Oyashio, which may be caused by the small density difference between the Oyashio and the TWC waters and the southward migration of main front of TWC, permits the Oyashio water to intrude along the Hidaka shelf slope.     

Evaluation of the flushing rates of Apalachicola Bay, Florida via natural geochemical tracers

We used naturally occurring radium isotopes as tracers of water exchange in Apalachicola Bay, a shallow coastal-plain estuary in northwestern Florida. The bay receives fresh water and radium from the Apalachicola River, and mixes with Gulf of Mexico waters through four inlets. We deployed moored buoys with attached Mn-fibers at several stations throughout the estuary during two summer and two winter periods. After deployment for at least one tidal cycle we measured the ratio of the two short-lived radium isotopes ²²³Ra (half-life = 11 d) and ²²⁴Ra (3.6 d) to estimate “radium ages” of the water in the bay.During our four seasonal deployments the river discharge ranged from 338 to 1016 m³ s^− 1. According to our calculations the water turnover time in the bay during these samplings ranged from 6 to 12 days. Age contours in the bay showed that winds and tides as well as river discharge influence the water movement and the residence time of freshwater in the bay. We also calculated the mean age of river water in the bay which was between 5 to 9 days during the studied periods. We suggest that this approach can be used to quantify transport processes of dissolved substances in the bay. For example, soluble nutrient or pollutant transport rates from a point source could be examined. We conclude that the radium age technique is well suited for flushing rate calculations in river dominated shallow estuaries.     

Wind-dependent formation of phytoplankton spring bloom in Otsuchi Bay,a ria in Sanriku,Japan

Spring blooms of phytoplankton composed of centric diatoms developed in late February, March, and April in Otsuchi Bay on Sanriku ria coast, Japan. During this period, associated with prolonged seasonal west wind (>1 day), intense exchange of waters occurred between inside and outside the bay: outflow of nearsurface brackish water over inflow of oceanic water at depth. This circulation interrupted formation of the blooms, and transported phytoplankton populations seaward. By such water movements, a significant amount of nutrients in the bay was carried out, otherwise replenished into the bay, depending on water masses located outside the bay. Owing to irregular features of wind events, a bloom lasted from several days to a week. From February to April, supply of nutrients seemed to be replete except for the latter half of the bloom period, and estimates of the critical depth exceeded the depth of the bottom consistently. Thus, net growth of phytoplankton was expected throughout the observation period, and potentially blooms could be formed. However, the blooms were only formed under calm weather. We hypothesize that the exchange of waters dilutes populations in the bay, and that formation of the bloom, that is, accumulation of biomass depends on a balance between the growth of phytoplankton and the dilution of bay water.     

Field Study of the Space Uniformity of Meteorological and Wave Parameters in the Coastal Zone. On the Problem of Calibration of a Side-Looking Radar on the <Emphasis Type="Italic">Sich-1M</Emphasis> Satellite as an Instrument for Measuring Wind Velocity over the Sea

We study the problem of subsatellite calibration of a side-looking radar (SLR) of the Sich-1M satellite regarded as an instrument for the evaluation of the velocity of surface wind and discuss the possibility of application of the meteorological and wave parameters measured from the stationary oceanographic platform of the Experimental Department of the Marine Hydrophysical Institute (Ukrainian Academy of Sciences) for their evaluation in the remote regions of the sea. These regions can be observed with the help of the SLR without errors introduced by the appearance of the coast in elements of space resolution. To prove the indicated possibility experimentally, we perform simultaneous measurements of the water and air temperatures, wind velocity, and the characteristics of waves both from the platform and in the water area neighboring with the platform on the side of the sea at distances of up to 4.8 km. The quantitative estimates of the degree of space uniformity of the analyzed parameters are deduced under the conditions of stable inshore wind. A conclusion is made that the platform can be used for subsatellite measurements aimed at the validation and improvement of the algorithm of reconstruction of the velocity of surface wind by using the SLR of the Sich-1M satellite. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 3, pp. 31–43, May–June, 2005.     

Technologies of measurements of the sea level

We analyze the contemporary methods and means of measurements of the sea level and inland waters, describe a CTD-meter designed at the Marine Hydrophysical Institute of the Ukrainian National of Science for the determination of the sea level, formulate the requirements to the perfect meter of the water level, and demonstrate that an electronic sounding stick based on the distributed Walsh thermoprofilometers can play the role of a device of this kind.     

胶州湾水域重金属铬的分布及迁移

根据1979年的胶州湾水域调查资料,分析了重金属铬在胶州湾水域的分布、迁移和季节变化。研究结果表明;春季,胶州湾水城铬污染较轻,大部分海域水质状况较好,而到夏季没有受到污染。在时空分布上,春季,铬污染形成了明显的梯度,由东北向西南方向递减,从112．3μg／L降低到0．2μg／L。夏季,铬的水平分布比较均匀,表层水体铬的含量较低,范围在0．10～1．40μg／L之间波动。因此认为,1979年整个胶州湾水域的重金属铬属于面污染源。而且,当铬进入胶州湾海域后,很快吸附在水体中的悬浮颗粒上,并被水流较快地带离胶州湾水城,几乎没有在胶州湾水域表、底层留下污染痕迹。