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Number of results: 97
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Abstract

he paper contains results of a in situ research main task of which was to detect objects buried, partially or completely, in the sea bottom. Object detecting technologies employing acoustic wave sources based on nonlinear interaction of elastic waves require application of parametric sound sources. Detection of objects buried in the sea bottom with the use of classic hydroacoustic devices such as the sidescan sonar or multibeam echosounder proves ineffective. Wave frequencies used in such devices are generally larger than tens of kHz. This results in the fact that almost the whole acoustic energy is reflected from the bottom. On the other hand, parametric echosounders radiate waves with low frequency and narrow beam patterns which ensure high spatial resolution and allows to penetrate the sea bottom to depths of the order of tens of meters. This allows to detect objects that can be interesting, among other things, from archaeological or military point of view.
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Authors and Affiliations

Eugeniusz Kozaczka
Grażyna Grelowska
Sławomir Kozaczka
Wojciech Szymczak
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Abstract

The understanding the influence of biological processes on the characteristics of the signals backscattered by the sea floor is crucial in the development of the hydroacoustical benthic habitat classification techniques. The impact of the microphytobenthos photosynthesis on the acoustical backscattering properties of the Atlantic sandy sediments was previously demonstrated by Holliday et al. (2004) and Wildman and Huettel (2012). To account for the sensitivity of the hydroacoustical classification techniques to the backscattering properties of local marine sediments, it is important to understand the microphytobenthos photosynthesis impact for the Baltic Sea where the techniques are being actively developed now. This is the main motivation of the paper. In the paper the influence of the microphytobenthos photosynthesis on the characteristics of the echo signals reflected by sandy sediments in the typical Baltic temperature and the salinity conditions is discussed. The interdisciplinary multiday laboratory experiment was conducted to study the impact of benthic microalgal photosynthesis on the characteristics of the echo signal reflected by sandy sediments. Hydroacoustical data were collected under controlled constant light, temperature and salinity conditions. The oxygen content at different levels of the water column was simultaneously monitored.
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Authors and Affiliations

Natalia Górska
Ewa Kowalska-Duda
Jacek Marszal
Jan Schmidt
Zygmunt Klusek
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Abstract

Four halacarid species: Agaue agauoides, Agaue parva, Bradyagaue drygalskii, and Halacarus minor have been extracted from bottom samples taken in Admiralty Bay, King George Island, South Shetland Islands, another four, Colobocerasides auster, Halacarus arnaudi, Lohmannella fukushimai, and L. gaussi, from Kapp Norvegia, Atka and Halley Bay, Weddell Sea. Most of these species are widespread around Antarctica and adjacent islands. Diagnostic characters are outlined. An annotated list presents 66 halacarid species reported from south of the Antarctic Polar Front. © 2016 Polish Academy of Sciences 2016.
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Authors and Affiliations

Ilse Bartsch
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Abstract

Zoidbergus , a new genus of Apseudidae, is described for deep−water Tanaidacea classified previously in the genus Apseudes : A. abyssalis , A. lagenirostris , A. paragracilis , A. tenuimanus , A. tenuis and A. vicinus . The new genus differs from Apseudes s. str. by having acute eyelobes without visual elements, elongated second article of mandibular palp, and carpus of pereopods 2–3 longer than or as long as propodus. Zoidbergus gen. n. can also be distinguished from Apseudes s. str. by the lack of large bases of pereopods 5–6 covered by numerous plumose setae as well as the lack of dense plumose setation on lateral margins of pereonites and pleonites. By general body habitus and structure of pereopods Zoidbergus gen. n. resembles the apseudid genus Leviapseudes , although the genera can be distinguished by the presence of leaf−shaped seta and elongated pereonites 3–6 in Leviapseudes . Based on specimens collected during the IceAGE1 Cruise in September 2011, Zoidbergus tenuis is redescribed and morphology of an undescribed species Zoidbergus sp. A is provided. Supplementary description for Zoidbergus vicinus is given based on type material from Statens Naturhistoriske Museum, University of Copenhagen. Additionally comments on the other deep water Apseudes species: A. siegi and A. vitjazi , are given.
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Authors and Affiliations

Piotr Jóźwiak
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Abstract

The climatic change on King George Island (KGI) in the South Shetland Islands, Antarctica, in the years of 1948–2011 are presented. In the reference period, a statistically significant increase in the air temperature (0.19 ° C/10 years, 1.2 ° C in the analysed period) occurred along with a decrease in atmospheric pressure (−0.36 hPa/10 years, 2.3 hPa). In winter time, the warming up is more than twice as large as in summer. This leads to decrease in the amplitude of the annual cycle of air temperature. On KGI, there is also a warming trend of daily maximum and daily minimum air temperature. The evidently faster increase in daily minimum results in a decrease of the diurnal temperature range. The largest changes of air pressure took place in the summertime (−0.58 hPa/10 years) and winter (−0.34 hPa/10 years). The Semiannual Oscillation pattern of air pressure was disturbed. Climate changes on KGI are correlated with changing surface temperatures of the ocean and the concentration of sea ice. The precipitation on KGI is characterised by substantial variability year to year. In the analysed period, no statistically significant trend in atmospheric precipitation can be observed. The climate change on KGI results in substantial and rapid changes in the environment, which poses a great threat to the local ecosystem.
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Authors and Affiliations

Marek Kejna
Andrzej Araźny
Ireneusz Sobota
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Abstract

Metals are useful raw materials used in various industries. But one of the side-effects of their production is pollution of the marine environment.
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Authors and Affiliations

Jacek Bełdowski
1
Magdalena Bełdowska
2

  1. PAS Institute of Oceanology in Sopot
  2. Faculty of Oceanography and Geography,University of Gdańsk
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Abstract

A significant part of hard coal production (15–19% in the years 2010–2017, i.e. 1.0–1.3 billion

tons per year) is traded on the international market. The majority of coal trade takes place by sea,

accounting for 91–94% of the total coal trade. The article discusses the share of coal in international

seaborne trade and the largest coal ports. Coal is one the five major bulk commodities (in addition

to iron ore, grain, bauxite, alumina, and phosphate rock). In the years 2010–2016, the share of coal

in international seaborne trade and major bulk commodities was 36–41% and 11–12%, respectively.

Based on the analysis of coal throughput in different ports worldwide, the ports with the

largest throughput include the ports of Qinhuangdao (China), Newcastle (Australia), and Richards

Bay (South Africa). For 2013–2017, their throughput amounted to a total of 411–476 million tons

of coal. The largest coal exporting countries were: Australia, Indonesia, Russia, Colombia, South

Africa, and the US (a total of 85% share in global coal exports), while the largest importers are

Asian countries: China, India, Japan, South Korea and Taiwan (a 64% share in global imports). In

Europe, Germany is the largest importer of coal (54 million tons imported in 2016). The article also

discusses the freight costs and the bulk carrier fleet. Taking the price of coal at the recipient’s (i.e.

at the importer’s port) into account, the share of freight costs in the CIF price of steam coal (the

price of a good delivered at the frontier of the importing country) was at the level of 10–14%. In

the years 2010–2016, the share of bulk carriers in the world fleet was in the range of 11–15%. In

terms of tonnage, bulk carriers accounted for 31–35% of the total tonnage of all types of ships in

the world. The share of new (1–4 years) bulk carriers in the total number of ships on a global scale

in the years 2010–2016 was 29–46%.

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Authors and Affiliations

Katarzyna Stala-Szlugaj
Zbigniew Grudziński
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Abstract

The properties of the nonlinear phenomenon in water, including sea water, have been well known for many decades. The feature of the non homogeneous distribution of the speed of sound along the depth of the sea is very interesting from the physical and technical point of view. It is important especially in the observation of underwater area by means of acoustical method (Grelowska et al., 2013; 2014). The observation of the underwater space has been carried out for more than hundred years. In the second half of the twentieth century we observed very intense trend of development of the measuring methods of underwater sound speed. It was done mainly in the linear sound propagation aspect. At the end of 20th century nonlinear devices were invented. Thus, from this point of view, knowledge on the nonlinear properties of the sea water is the matter of interest. The phenomenon of nonlinear distortion of elastic waves, and the same the efficiency of nonlinear transfer of energy from the primary wave to the higher harmonic components depend on properties of the medium, especially on the material constant known as the nonlinearity parameter B/A. The Baltic Sea is a specific reservoir with untypically low salinity and low depth (Grelowska, 2000). In the paper results of investigation of nonlinear properties of the South and the Central Baltic by means of thermodynamic method are presented.
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Authors and Affiliations

Grażyna Grelowska
Eugeniusz Kozaczka
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Abstract

A total of 142 cods: 60 from the South−East Ground of Bear Island and 82 from the Pomeranian Bay (Baltic Sea) were examined for their ecto− and endoparasites. Twenty different parasite species, comprising one Myxosporea, three Cestoda, four Digenea, seven Nematoda, three Acanthocephala and two Crustacea were found. The parasite component communities comprised 1446 individuals (17 species, six higher taxa) from the Bear Island and 6588 individuals (nine species, three higher taxa) from Pomeranian Bay. The observed parasite host specificity was low, and the intensity in a single fish ranged from one to 279 specimens. The eudominant parasite species were Echinorhynchus gadi , Hemiurus levinseni and Contracaecum osculatum . The dominant parasite communities from the Bear Is − land were nematodes, but acanthocephalans dominated in cod from the Baltic Sea. It appears that one group of parasites, better adapted for the specific conditions of the macrohabitat, has replaced another. The most prevalent parasites were E. gadi , Anisakis simplex , C. osculatum and Hysterothylacium aduncum , and the mean values of crowding were the highest for E. gadi and Pomphorhynchus laevis . The nematode Camallanus lacustris was noted in this host species for the first time. Only six species of parasites were common to cod from both fishing grounds
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Authors and Affiliations

Ewa Sobecka
Ewa Łuczak
Beata Więcaszek
Artur Antoszek
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Abstract

The transport pipeline of lifting the underwater minerals to the surface of the water onto the ship during the movement of the vessel takes in the water a curved deformed shape. Analysis of the state of stability of the pipeline showed that if the flow velocity of fluid in the pipeline exceeds a certain critical value Vkr, then its small random deviations from the equilibrium position may develop into deviations of large amplitude. The cause of instability is the presence of the centrifugal force of the moving fluid mass, which occurs in places of curvature of the axis of the pipeline and seeks to increase this curvature when the ends of the pipeline are fixed. When the critical flow velocity is reached, the internal force factors become unable to compensate for the action of centrifugal force, as a result of that a loss of stability occurs. Equations describing this dynamic state of the pipeline are presented in the article.
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Bibliography

[1] Benjamin T .B. Dynamic of a system of articulated pipes conveying fluid. I Theory. Proc. Royal Soc. 261, 457-486 (1961), II Experiment, 487-99.
[2] Chung J .S., Bao-Rang Cheng, Huttelmaier H .P. Three-Dimensional Coupled Responses of a Vertical Deep-Ocean Pipe: Part II. Excitation at Pipe Top and External Torsion, International Journal of Offshore and Polar Engineering 4, 4, December 1994 (ISSN 1053-5381).
[3] Goman O.G., Kirichenko E.A., Vishnyak E.A. Calculation of hydrodynamic loads on the elements of submersible structures of deep-water slurry pipelines. System Technologies: A collection of scientific papers – Dnipropetrovsk: RVKIA Ukraine 8, 17-23 (1999) [in Russian].
[4] Gregory R .W., Paidoussis M .P. Unstable oscillation of turbular cantilevers, conveying fluid. I Theory. Proc. of the Royal Soc., London, Ser. A, 293, 528-542 (1966).
[5] Handelman H.M. Quart. Appl. Math. 13, 326-334 (1955).
[6] Kirichenko E.A. Possible cases of simplification of the system of equations of oscillations of deep-water slurry pipelines in a flat formulation. Mining, electromechanics and automatics: A collection of scientific papers – Dnipropetrovsk: RVKNGA of Ukraine 4, 137-142 (1999) [in Russian].
[7] Long R.H. Jr. Experimental and theoretical study of transverse vibration of a tube containing flowing fluid. J. App. Mech. 22, 1, 65-68 (1955).
[8] Niordson F .I.N. Vibrations of cylindrical tube containing flowing fluid. Trans. of the Royal Inst. of Tech., Stockholm, Sweden, 1953, No.73. 392
[9] Szelangiewicz T., Żelazny K., Buczkowski R., Computer simulations of deformations and tensions in the pipelines of hydraulic lifting systems, Scientific Journals of the Maritime University of Szczecin – Zeszyty Naukowe Akademii Morskiej w Szczecinie 52 (124), 37-44 (2017). DOI : https://doi.org/10.17402/243
[10] Yao Nijun, Cao Bin, Xia Jianxin, Pressure loss of flexible hose in deep-sea mining system. 18th International Conference on TRANSPORT AND SEDIMENTATION OF SOLID PARTICLES 11-15 September 2017, Prague, Czech Republic. ISBN 978-83-7717-269-8.
[11] Yu Hong-yun, Liu Shao-jun, Dynamics of vertical pipe in deep-ocean mining system, J. Cent. South Univ. Technol. (2007) 04-0552-05. DOI : https://doi.org/10.1007/s11771-007-0106-0
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Authors and Affiliations

Jerzy Sobota
1
ORCID: ORCID
Xia Jianxin
2
ORCID: ORCID
Evgeniy Kirichenko
3
ORCID: ORCID

  1. Wrocław University of E nvironmental and Life Sciences, Poland
  2. Minzu University of China, Beijing, China
  3. Mining University, Dnipropetrovsk, Ukraine
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Abstract

How does inflowing river water affect the quality of water in the Baltic Sea? Why are the chemicals used in agriculture so dangerous for seas, and what future lies in store for the Baltic?

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Authors and Affiliations

Jan Marcin Węsławski
ORCID: ORCID
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Abstract

Altogether 105 algal taxa were identified including 101 diatom species. Chaetoceros criophilus was dominant in the western part of the study area influenced by waters from the Bellingshausen Sea. Corethron criophilum was abundant in the Weddcll Sea water mass found to the east of 53.5°W meridian. Nitzschia cylindrus common in the ice-melt samples was dominant in only two net phytoplankton collections obtained at the ice-edge zone. Additional samples from Admiralty Bay, at King George Island revealed the dominance of Chaetoceros socialis and the presence of many tychoplankton species. Very few diatom cells were found in the open waters of the Bransfield Strait which combined with the presence of krill, suggested intensive grazing by herbivores. The unstable waters of the Weddell-Scotia Confluence area contained little phytoplankton except for a station dominated by Phaeocystis pouchetii. Greater cell densities were related to warm, lower salinity Weddell Sea water of summer modification found in the surface layer east from 49°W.

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Authors and Affiliations

Ryszard Ligowski
Elżbieta Kopczyńska
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Abstract

The Author tries to “think out of the box”, presenting “Sponsalia ex hoc mundo” (“Hand fastening out of this world”). The title reflects the view that the outer space sciences and the sea sciences are analytically separable, but practically interlinked. It might be observed in the context of space technology and satellite technics, a new system of management and government, as well as a new system of law and policy. Nowadays, the outer space infrastructure (the use of artificial Earth satellites for Direct Television Broadcasting, communications, remote sensing, navigation, military missiles) affects infrastructure of our Planet, including maritime infrastructure. There is, therefore, the need for a new face of integrated system of science and practice.

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Authors and Affiliations

Zdzisław Brodecki
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Abstract

Joint action by the countries surrounding the Baltic is crucial for the conservation of the sea’s unique ecosystem.
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Authors and Affiliations

Blanka Pajda
1
Agata Zaborska
1

  1. PAS Institute of Oceanology in Sopot
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Abstract

The article presents a review of the researches on sea and atmospheric physics conducted by the Polish expeditions in Antarctica from 1977 to 1990.

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Authors and Affiliations

Henryk Gurgul
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Abstract

Results of an oceanographic survey along the edge of drifting pack ice in the area between Elephant Island and the South Orkney Islands are reported. The influence of sea ice on hydrological factors was very weak. It was not possible to develop oceanographic features characteristic for marginal sea-ice zones in the areas with well marked surface currents and dynamic hydrological conditions. The spatial distribution of chlorophyll was governed by water stability, although during our survey, areas with enhanced vertical stability could not be described in terms of a sea-ice edge influence.

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Authors and Affiliations

Maciej Lipski
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Abstract

The highest concentrations of algal cells (1.1 x l0 6 litre- 1 ) and of algal carbon (20 μg litre -1 ) were associated with a lens of ice melt water in the northeast of the study area. Phytoflagellates were dominant at all stations with greater numbers always in the 0 - 20 m surface layer and with the peaks of Cryptophyceae in the open waters and also near the ice edge east of 50° W. Picoplankton flagellates and monads (1.5-5.0 μ) were generally next in abundance and most important numerically in the near ice stations in the western part of the study area. Parasinophyceae were usually more abundant than Nitzschia cylindrus (Grunow) Hasle, the only common diatom species found mainly in the western near ice edge stations. The presence olN.cylindrus, dominant in the pack ice and in phytoplankton near the ice edge, shows that algae released from ice may act as an inoculum for the phytoplankton.

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Authors and Affiliations

Elżbieta Kopczyńska
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Abstract

The paper discusses the first find of a bullet core from the territory of Bulgaria. This core fills in a gap in the occurrence of this technology in between the Marmara Sea basin and the northwestern part of the Pontic region. Because the core from the vicinity of Varna is a surface find it is difficult to determine its chronological position.

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Authors and Affiliations

Ivan Gatsov
Petranka Nedelcheva
Małgorzata Kaczanowska
Janusz K. Kozłowski
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Abstract

One of the fundamental problems of modern geodesy is precise de fi nition of the gravitational fi eld and its changes in time. This is essential in positioning and navigation, geophysics, geodynamics, oceanography and other sciences related to the climate and Earth’s environment. One of the major sources of gravity data is satellite altimetry that provides gravity data with almost 75% surface of the Earth. Satellite altimetry also provides data to study local, regional and global geophysical processes, the geoid model in the areas of oceans and seas. This technique can be successfully used to study the ocean mean dynamic topography. The results of the investigations and possible products of altimetry will provide a good material for the GGOS (Global Geodetic Observing System) and institutions of IAS (International Altimetry Service). This paper presents the achievements in satellite altimetry in all the above disciplines obtained in the last years. First very shorly basic concept of satellite altimetry is given. In order to obtain the highest accuracy on range measurements over the ocean improved of altimetry waveforms performed on the ground is described. Next, signi fi cant improvements of sea and ocean gravity anomalies models developed presently is shown. Study of sea level and its extremes examined, around European and Australian coasts using tide gauges data and satellite altimetry measurements were described. Then investigations of the phenomenon of the ocean tides, calibration of altimeters, studies of rivers and ice-sheets in the last years are given.
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Authors and Affiliations

Adam Bolesław Łyszkowicz
Anna Bernatowicz
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Abstract

The shipping noise near channels and ports is an important contribution to the ambient noise level, and the depth of these sites is often less than 100 m. However less attention has been paid to the measurement in shallow water environments (Brooker, Humphrey, 2016). This paper presents extensive measurements made on the URN (underwater radiated noise) of a small fishing boat in the South China Sea with 87 m depth. The URN data showed that the noise below 30 Hz was dominated by the background noise. The transmission loss (TL) was modelled with FEM (finite element method) and ray tracing according to the realistic environmental parameters in situ. The discrepancy between the modelled results and the results using simple law demonstrates both sea surface and bottom have significant effect on TL for the shallow water, especially at low frequencies. Inspired by the modelling methodology in AQUO (Achieve QUieter Oceans) project (Audoly et al., 2015), a predicted model applied to a typical fishing boat was built, which showed that the URN at frequencies below and above 100 Hz was dominated by non-cavitation propeller noise and mechanical noise, respectively. The agreement between predicted results and measured results also demonstrates that this modelling methodology is effective to some extent.
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Authors and Affiliations

Peng Zilong
Fan Jun
Wang Bin
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Abstract

Study of the sea noise has been a subject of interest for many years. The first works in this scope were published at the turn of the twentieth century by Knudsen (Knudsen et al., 1948) and G. Wenz (Wenz, 1962). Disturbances called “shipping noise” are one of the important components of the sea noise. In this work the results of an experimental research of underwater noise produced by a small ship of a classic propulsion are presented. A linear receiving antenna composed of two orthogonal components was used in the investigation. Identification of the main sources of acoustic waves related with the ship was achieved. In addition, the intensity of the wave was measured. The research was performed in conditions of the shallow sea.
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Authors and Affiliations

Grażyna Grelowska
Eugeniusz Kozaczka
Sławomir Kozaczka
Wojciech Szymczak

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