Cesium-137 in the salt lakes of Сrimea

Sea radiance coefficient, defined as the ratio of the sunlight reflected by the water bulk to the sunlight illuminating the water surface, is one of the most informative optical characteristics of the seawater that can be obtained by passive remote sensing. We got the sea radiance coefficient spectra by processing the data obtained in measurements from board a moving ship. Using sea radiance coefficient optical spectra it is possible to estimate water constituents concentration and their distribution over the aquatory of interest. However, thus obtained sea radiance coefficient spectra are strongly affected by weather and measurement conditions and needs some calibration. It was shown that practically all the spectra of sea radiance coefficient have some generic peculiarities regardless of the type of sea waters. These peculiarities can be explained by the spectrum of pure sea water absorption. Taking this into account a new calibration method was developed. The measurements were carried out with the portative spectroradiometers from board a ship in the five different seas: at the north-east coast of the Black Sea, in the Gdansk Bay of the Baltic Sea, in the west part of the Aral Sea, in the Kara Sea with the Ob’ Bay and in the Philippine Sea at the coast of Taiwan. The new method of calibration was applied to the obtained spectra of the sea radiance coefficient that enabled us to get the corresponding absorption spectra and estimate the water constituents concentration in every region. The obtained concentration estimates were compared to the values obtained in water samples taken during the same measurement cycle and available data from other investigations. The revealed peculiarities of the sea radiance coefficient spectra in the aquatories under exploration were compared to the corresponding water content and some characteristic features were discussed.

Download Full-text

Hydrology and circulation in the North Aegean (eastern Mediterranean) throughout 1997 and 1998

Mediterranean Marine Science ◽

10.12681/mms.254 ◽

2002 ◽

Vol 3 (1) ◽

pp. 5 ◽

Cited By ~ 87

Author(s):

V. ZERVAKIS ◽

D. GEORGOPOULOS

Keyword(s):

Surface Layer ◽

Black Sea ◽

Sea Water ◽

Saline Water ◽

Eastern Mediterranean ◽

Late Summer ◽

Cyclonic Circulation ◽

The Black Sea ◽

The North ◽

North Aegean

The combination of two research projects offered us the opportunity to perform a comprehensive study of the seasonal evolution of the hydrological structure and the circulation of the North Aegean Sea, at the northern extremes of the eastern Mediterranean. The combination of brackish water inflow from the Dardanelles and the sea-bottom relief dictate the significant differences between the North and South Aegean water columns. The relatively warm and highly saline South Aegean waters enter the North Aegean through the dominant cyclonic circulation of the basin. In the North Aegean, three layers of distinct water masses of very different properties are observed: The 20-50 m thick surface layer is occupied mainly by Black Sea Water, modified on its way through the Bosphorus, the Sea of Marmara and the Dardanelles. Below the surface layer there is warm and highly saline water originating in the South Aegean and the Levantine, extending down to 350-400 m depth. Below this layer, the deeper-than-400 m basins of the North Aegean contain locally formed, very dense water with different θ /S characteristics at each subbasin. The circulation is characterised by a series of permanent, semi-permanent and transient mesoscale features, overlaid on the general slow cyclonic circulation of the Aegean. The mesoscale activity, while not necessarily important in enhancing isopycnal mixing in the region, in combination with the very high stratification of the upper layers, however, increases the residence time of the water of the upper layers in the general area of the North Aegean. As a result, water having out-flowed from the Black Sea in the winter, forms a separate distinct layer in the region in spring (lying between “younger” BSW and the Levantine origin water), and is still traceable in the water column in late summer.

Download Full-text

LONG-TERM MONITORING OF SEASONAL AND INTERANNUAL VARIABILITY OF HYDROLOGICAL STRUCTURE IN COASTAL ZONE OF THE NORTH-EASTERN BLACK SEA

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b4317195e3a ◽

2017 ◽

Author(s):

O. Podymov ◽

N. Kuzevanova ◽

A. Khvorosch ◽

...

Keyword(s):

Coastal Zone ◽

Black Sea ◽

Hydrogen Sulphide ◽

Sea Water ◽

The Black Sea ◽

Homogeneous Layer ◽

Marmara Sea ◽

The North ◽

North Eastern ◽

North Eastern Part

The work demonstrates the results of the 6-years complex ship-borne monitoring of coastal zone in the north-eastern part of the Black Sea, carried out by the Southern Branch of P.P.Shirshov Institute of Oceanology, RAS, on a marine cross-section at the Blue Bay (Gelendzhik) beam 1-2 times per month. Climatic changes and eutrophication exert a significant impact on the sea water at the coastal area. In case of the Black Sea these factors pile up with a permanent hydrogen sulphide contamination of the sea water below 80-200 meters depth (depending on the season and distance from the shore). Strong pycno-halocline at the depths from 70 to 160 meters, formed due to the inflow of high salinity water from the Marmara Sea, inhibits the mixing between the water layers and, as a result, also limits the oxygen transport into the deeper layers. The winter cooling reduces the pycno-halocline and enriches the top active layer, down to the cold intermediate layer (CIL), with oxygen and nutrients, which subsequently lead to a vernal phytoplankton bloom. Formation of the thermocline and upper quasi-homogeneous layer (UQL), caused by the water warming in spring, at large extent determines a thickness of phytoplankton-rich layer during the spring and summer seasons. The work demonstrates seasonal and interannual dynamics of the UQL, thermocline, CIL and hydrogen sulphide boundary position in the coastal zone of the north-eastern part of the Black Sea.

Download Full-text

Black Sea coastal forecasting systems

Ocean Science Discussions ◽

10.5194/osd-8-1055-2011 ◽

2011 ◽

Vol 8 (3) ◽

pp. 1055-1088 ◽

Cited By ~ 1

Author(s):

A. I. Kubryakov ◽

G. K. Korotaev ◽

V. L. Dorofeyev ◽

Yu. B. Ratner ◽

A. Palazov ◽

...

Keyword(s):

Coastal Zone ◽

Black Sea ◽

Ecosystem Model ◽

The Black Sea ◽

Western Basin ◽

The North ◽

North Eastern ◽

The Crimea ◽

Forecasting System ◽

Crimea Peninsula

Abstract. The Black Sea coastal nowcasting and forecasting system was built within the framework of EU FP6 ECOOP project for five regions: the south-western basin along the coasts of Bulgaria and Turkey, the North-Western shelf along the Romanian and Ukrainian coasts, coastal zone around of the Crimea peninsula, the north-eastern Russian coastal zone and the coastal zone of Georgia. The system operates in the real-time mode during the ECOOP project and afterwards. The forecasts include temperature, salinity and current velocity fields. Ecosystem model operates in the off-line mode near the Crimea coast.

Download Full-text

INTER-annual/decadal variability of the north Aegean Sea hydrodynamics over 1960-2000

Mediterranean Marine Science ◽

10.12681/mms.852 ◽

2014 ◽

Vol 15 (4) ◽

pp. 696 ◽

Cited By ~ 1

Author(s):

V. VERVATIS ◽

N. SKLIRIS ◽

S. S. SOFIANOS

Keyword(s):

Decadal Variability ◽

Sea Water ◽

Salt Content ◽

Aegean Sea ◽

The Black Sea ◽

Minor Role ◽

Freshwater Flux ◽

The North ◽

North Aegean ◽

North Aegean Sea

Results from a high-resolution hindcast model experiment, supported by available observations, reveal an increasing salinity trend in the north Aegean during the Eastern Mediterranean Transient (EMT), largely controlled by increases in the flow rate and salinity of water masses of Levantine origin entering the domain through the Myconos-Ikaria strait as a response to an acceleration of the Aegean thermohaline cell. Changes in the Dardanelles inflow (increasing salinity) and in the surface freshwater flux (increasing Evaporation-Precipitation), although both contribute to a higher salt content of the basin during the EMT, play a minor role in the inter-annual/decadal variability of the freshwater budget. A long-term decreasing temperature trend is observed from the 1960s to the early 1990s. It is superimposed on the salinity-preconditioning phase over the 1980s and early 1990s. Both signals are, concomitantly, favouring conditions for intense Dense Water Formation (DWF) in the north Aegean Sea. In addition, the northward displacement of the Black Sea Water front over the EMT, leads to the expansion of convective cells towards the north and to higher formation rates associated with both colder and saltier surface waters.

Download Full-text

LONG-TERM MONITORING OF SEASONAL AND INTERANNUAL VARIABILITY OF HYDROLOGICAL STRUCTURE IN COASTAL ZONE OF THE NORTH-EASTERN BLACK SEA

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b93b554e1b8.09734764 ◽

2017 ◽

Author(s):

O. Podymov ◽

N. Kuzevanova ◽

A. Khvorosch ◽

...

Keyword(s):

Coastal Zone ◽

Black Sea ◽

Hydrogen Sulphide ◽

Sea Water ◽

The Black Sea ◽

Homogeneous Layer ◽

Marmara Sea ◽

The North ◽

North Eastern ◽

North Eastern Part

The work demonstrates the results of the 6-years complex ship-borne monitoring of coastal zone in the north-eastern part of the Black Sea, carried out by the Southern Branch of P.P.Shirshov Institute of Oceanology, RAS, on a marine cross-section at the Blue Bay (Gelendzhik) beam 1-2 times per month. Climatic changes and eutrophication exert a significant impact on the sea water at the coastal area. In case of the Black Sea these factors pile up with a permanent hydrogen sulphide contamination of the sea water below 80-200 meters depth (depending on the season and distance from the shore). Strong pycno-halocline at the depths from 70 to 160 meters, formed due to the inflow of high salinity water from the Marmara Sea, inhibits the mixing between the water layers and, as a result, also limits the oxygen transport into the deeper layers. The winter cooling reduces the pycno-halocline and enriches the top active layer, down to the cold intermediate layer (CIL), with oxygen and nutrients, which subsequently lead to a vernal phytoplankton bloom. Formation of the thermocline and upper quasi-homogeneous layer (UQL), caused by the water warming in spring, at large extent determines a thickness of phytoplankton-rich layer during the spring and summer seasons. The work demonstrates seasonal and interannual dynamics of the UQL, thermocline, CIL and hydrogen sulphide boundary position in the coastal zone of the north-eastern part of the Black Sea.

Download Full-text

Upwellings and water circulation of the north-western shelf of the Black Sea in the summer of 2017

Ukrainian hydrometeorological journal ◽

10.31481/uhmj.24.2019.10 ◽

2019 ◽

pp. 105-114

Author(s):

Yu. I. Popov ◽

A. V. Matveev

Keyword(s):

Black Sea ◽

Coastal Upwelling ◽

Sea Water ◽

Water Circulation ◽

Abnormal Development ◽

The Black Sea ◽

Landsat 8 ◽

Summer Circulation ◽

The North ◽

North Western

On the basis of satellite and field atmospheric and marine observations, the water circulation processes of the north-western shelf (the NWS) of the Black Sea in the summer of 2017 were studied. The study indicated high stability of summer offshore winds of northern and north-northwest directions and 12 cases of coastal upwelling. Three cases of upwelling were instrumentally detected on the across-the-shore oceanographic sections during seasonal field works performed by the oceanographic unit of the branch “Odesa Area of State Hydrographic Service” of the state institution "State Hydrographic Service of Ukraine (SHSU)". The increase of coastal water density led to an abnormally active transfer along the coast of the Danube-Dniester interfluve area to the northernmost parts of the NWS. In 2017 a visual manifestation of anticyclonic character of summer circulation of the NWS's water could be observed. The obtained data confirm the previous conclusions on frequent cases of change in summer periods of traditional cyclonic water circulation to the anticyclonic one. The abnormal development of the summer circulation regime allowed us to record for the first time the transfer of coccolithophores phytoplankton from the open sea to the northern regions of the NWS and to reveal its intraseasonal spatial transformation and development process duration. In the seaward part of the Gulf of Odessa a frequently repeated vortex formation of cyclonic vorticity with spatial dimensions of up to 7-8 miles and orbital velocities, according to the presented data, of 0.12–0.18 m.c-1, and according to the latest field work, of over 0.30 m.c-1, was found. When analyzing the considered situations associated with transfer and vorticity of sea water a significant role was played by high-resolution visual images obtained from Sentinel-2 and Landsat-8 satellites having a spatial resolution of 10 and 30 meters respectively, as well as by similar satellites of earlier modifications.

Download Full-text

Circulation and hydrological characteristics of the North Aegean Sea: a contribution from real-time buoy measurements

Mediterranean Marine Science ◽

10.12681/mms.255 ◽

2002 ◽

Vol 3 (1) ◽

pp. 21 ◽

Cited By ~ 20

Author(s):

K. NITTIS ◽

L. PERIVOLIOTIS

Keyword(s):

General Circulation ◽

Sea Water ◽

Aegean Sea ◽

The Black Sea ◽

Hydrological Characteristics ◽

The North ◽

Open Sea ◽

North Aegean ◽

North Aegean Sea ◽

Water Outflow

In the framework of the POSEIDON Project, a network of open sea oceanographic buoys equipped with meteorological and oceanographic sensors has been operational in the Aegean Sea since 1998. The analysis of upper-ocean physical data (currents at 3m, temperature and salinity at 3-40m depths) collected during the last 2 years from the stations of the North Aegean basin indicates a strong temporal variability of flow field and hydrological characteristics in both synoptic and seasonal time scales. The northern part of the basin is mainly influenced by the Black Sea Water outflow and the mesoscale variability of the corresponding thermohaline fronts, while the southern stations are influenced by the general circulation of the Aegean Sea with strong modulations caused by the seasonally varying atmospheric forcing.

Download Full-text

Benthic Hydrozoans as Potential Indicators of Water Masses and Anthropogenic Impact in the Sea of Marmara

Mediterranean Marine Science ◽

10.12681/mms.15117 ◽

2018 ◽

pp. 273 ◽

Cited By ~ 2

Author(s):

NUR EDA TOPÇU ◽

LUIS FELIPE MARTELL ◽

IZZET NOYAN YILMAZ ◽

MELEK ISINIBILIR

Keyword(s):

Black Sea ◽

Anthropogenic Impact ◽

Water Mass ◽

Cold Water ◽

Sea Water ◽

Water Masses ◽

The Black Sea ◽

Sea Of Marmara ◽

The North ◽

Maritime Traffic

Changes in the abundance and distribution of marine benthic hydrozoan species are indicative of variations in environmental conditions in the marine realm. The comparative analysis of such assemblages can improve our understanding of environmental and ecological conditions in the Sea of Marmara, a strongly stratified and heavily populated inland sea connecting the Aegean and Black seas, on route of national and international maritime traffic. We compared the hydrozoan assemblages occurring in harbours with those developed at natural sites, as well as the assemblages associated with the Black Sea water mass versus the Mediterranean water mass in the vicinities of the Prince Islands, the north-easternmost section of the Sea of Marmara. Sampling took place at 12 stations, once in March 2015 and once in August 2015 in order to cover species with both warm and cold water affinities. Multivariate analyses showed that benthic hydroid assemblages with both affinities differed significantly between the heavily trafficked harbours of the Prince Islands (connected to the metropolis of Istanbul) and areas without human settlements and maritime traffic. In addition, highly distinct hydroid assemblages were found characterizing both areas with water of Mediterranean origin and areas with water from Black Sea origin. Based on our results, we discuss the potential for the use of these organisms as indicators of water masses and anthropogenic impact at the regional level.

Download Full-text

Life-history and culture of Gracilaria foliifera (Rhodophyta) from South Devon

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400025042 ◽

1977 ◽

Vol 57 (3) ◽

pp. 577-586 ◽

Cited By ~ 34

Author(s):

J. McLachlan ◽

T. Edelstein

Keyword(s):

Life History ◽

North Atlantic ◽

Sea Water ◽

The Other ◽

Small Scale ◽

Original Material ◽

The North ◽

The World ◽

History Of ◽

The North Atlantic

Three species of Gracilaria, G. foliifera (Forsk.) Børg., G. verrucosa (Huds.) Papenf., and G. bursa-pastoris (S. M. Gmel.) Silva are recognized from the British flora (Parke & Dixon, 1976). In Britain G. verrucosa is widely distributed, although not common, whereas the other two species are rare and their distribution restricted (Newton, 1931). G. foliifera was described from the Red Sea as Fucus foliifer Forsk. (Børgesen, 1932). Plants referable to this species are now reported from various parts of the world, including both the eastern and western coasts of the north Atlantic (South & Cardinal, 1970; Taylor, 1957, 1960). However, considerable variation exists within species of Gracilaria (e.g. May, 1948), thus delimitation of species is often extremely difficult. Gracilaria foliifera from Britain (Fig. 1 A) is similar morphologically to the original material of Fucus foliifer as illustrated by Børgesen (1932, fig. 1), and therefore, we have limited our consideration to G. foliifera as it occurs in Britain (also see Harvey, 1846, pl. 15). However, little information is available on G. foliifera from the British Isles, and in the present instance we have investigated the life history of this alga in culture together with preliminary results on growth in small-scale tanks with running sea water.

Download Full-text