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EN
During the catastrophic flood caused by the ice dam in 1840, a new river mouth was created. Nevertheless some series of floods were observed in the next years. In order to facilitate of river waters run-off, the artificial crosscut was performed in 1891-1895 years. The artificial channel was opened in 31st of March 1895. Since, at the time of continuous exploitation of the channel, high effectiveness of the engineering project which is unique in the world scale has been confirmed. A permanent flood hazard for Gdansk city and adjacent lowland areas has been receded. Since this time, the external delta is being formed by acumulation of bed-loaded sediment that is transporting by the river. Consequently free run-off of the river water is reducing due to the external delta growing. During the years 2009-2014, detailed monitoring researches of the Vistula Canal as well as the Vistula River External Delta have been performed. The obtained results constitute a basis for the evaluation of flood risk in the area, as well as for prognosis of morphological changes of the Vistula River External Delta and sand supply to the Gulf of Gdansk. The state of the Vistula River mouth canal is briefly presented after 120 years of its history.
PL
Podczas katastrofalnej powodzi w 1840 roku doszło do utworzenia nowego ujścia, tak zwanej Wisły Śmiałej. W ciągu kolejnych lat nadal jednak wystepowały sytuacje powodzie. Podjeto wiec decyzję o wykonaniu odpowiedniego przekopu dla zapewnienia skutecznej ochrony przeciwpowodziowej. Przekop został otwarty 31 marca 1895 roku. Podczas kolejnych lat użytkowania Przekopu Wisły jego skuteczność została potwierdzona. Rumowisko piaszczyste wynoszone przez rzekę, składane przy jej ujsciu, zaczeło formowac stożek ujściowy – tak zwana zewnetrzną deltę.W miarę jej wzrostu następuje jednak zmiejszanie możliwości swobodnego spływu wód. W latach 2009-2014 przeprowadzono szczegółowe badania monitoringowe Przekopu Wisły i delty zewnętrznej. Uzyskane wyniki stanowią podstawę do oceny stanu przekopu i jego mozliwosci zapewnienia swobodnego spływu, wraz z prognozą zmian delty zewnetrznej i szacowniem ilosci dostarczanego materiału piaszczystego do Zatoki Gdańskiej.
PL
Celem pracy jest określenie stanu i zmian rzeźby stożka ujściowego Wisły Przekop, w okresie lat 2009-2014, w relacji do oceny warunków swobodnego spływu wód Wisły. Stanowi to istotny element dla oceny skuteczności zapobiegania powodziom w rejonie Żuław. Podstawę badań stanowią szczegółowe, monitoringowe pomiary batymetrii i morfometrii stożka wraz z kanałem doprowadzającym. Stosowano nowoczesną aparaturę (głównie DGPS RTK i specjalistyczne systemy nawigacyjne oraz echosondę wielowiązkową) zapewniającą uzyskanie cyfrowego modelu powierzchni dna, z decymetrową dokładnością położenia punktów. W kolejnych latach wykonano serię map batymetrycznych dla skali 1:10 000, map rzeźby i map różnicowych zmian rzeźby. Stwierdzone znaczne zmiany charakteru rzeźby (przy względnie niewielkim zmianach konturów stożka), wskazują na ich istotna rolę w kształtowaniu warunków swobodnego spływu wód Wisły.
EN
The aim of this study is to determine the state and changes of the Vistula Canal (Wisła Przekop) external delta relief, in the period of 2009-2014, and in relation to the assessment of the conditions of free runoff of the Vistula River waters. This is an important element for assessing the effectiveness of flood prevention in the area of Żuławy. The basis of the study are detailed bathymetry monitoring and morphometric measurements of the external delta with the supply channel. Modern equipment was used (mainly RTK and DGPS specialist navigation systems and multibeam echosounder), providing the obtainment of a digital model of the seabed surface, with decimeter accuracy of location points. In subsequent years, a series of bathymetric maps for the scale of 1:10 000 was made, as well as relief maps and maps of differential changes of the relief. The observed significant changes in the nature of the relief (with relatively small changes in the contours of the delta), indicate their important role in shaping the conditions of free runoff Vistula waters.
EN
Investigations of the geological structure and seabed dynamics as well as the morphological and sedimentological effects of sand extraction generated by different mining techniques were carried out in Polish waters of the Baltic Sea, NW of the Gulf of Gdańsk, at a water depth of 15-17 m. Three research cruises took place: just before, directly after and 11 months after dredging operations. Seismoacoustic profiling, a multibeam echosounder, a side-scan sonar, a 3 m vibro-corer and a box-corer were used during the research cruises. The grain size distribution and 137Cs content of the sand samples were determined. Marine shells were dated by the AMS14C technique and pollen analyses were carried out on samples of muddy sands lying below the marine sand. A 2 to 4.5 m thick layer of marine sands lies on the boulder till and locally on late Pleistocene ice margin lake deposits. The 137Cs content indicates that the 0.4-0.8 m thick sand layer is mobile during storms. After the dredging operations, four pits with diameters from 80 to 120 m, depths from 3 to 4.5 m and slopes with gradients up to 30-55° were measured. Several smaller irregularly shaped pits and double furrows 30-150 m in length and 0.3-0.5 m in depth were found. The sonar mosaic also shows a 50-100 m buffer zone of fine sand around the pits which flowed over the dredger's side with water and settled on the bottom. During one year after the dredging operation the furrows generated by trailer suction hopper dredging as well as the fine sand cover around the pits disappeared completely. The four post-dredging pits left by stationary suction dredging were shallower by 2-2.5 m, their diameters increased by 40-50 m, the gradient of the slopes was reduced by up to 5-10°, and the total volume was only about 3.5% smaller than directly after dredging.
4
Content available remote Organizacja morskich badań geofizycznych na przykładzie projektu "BalticPipe"
PL
Poszukiwania surowców zalegających na dnie morskim przez specjalistyczne jednostki badawcze przygotowane do prowadzenia badań geofizycznych za pomocą sond wielowiązkowych, sonarów bocznych, profilografów osadów, w warstwie organizacyjnej, nie różnią się od prowadzenia innych prac zmierzających do zdobycia informacji o budowie powierzchniowej warstwy dna morskiego. Informacje te niezbędne są do podjęcia prac związanych z przygotowaniem do układania podmorskich rurociągów, kabli energetycznych i telekomunikacyjnych czy budowy konstrukcji hydrotechnicznych. Przytoczona w tytule organizacja morskich badań geofizycznych zmierzających do zdobycia wiedzy na temat budowy dna na trasie planowanego gazociągu dobrze nadaje się do zilustrowania sposobu przygotowania i przeprowadzenia poszukiwań surowców zalegających na dnie morza przy użyciu metod akustycznych.
EN
Exploration of raw minerals on sea bottom using specialised research vessels, equipped in devices (multibeam echosounders, side scan sonars, subbottom profilers, etc.) for geophysical investigations, in its organizational aspects does not essentially differ from other activities aimed at investigation of surface sea bottom sediments. This information concerning sea bottom is also necessary for preparatory work before laying pipelines, power and telecommunication cables, and building hydraulic engineering constructions. The organization of geophysical investigations in the sea named in the title of the paper, aimed at gaining knowledge on sea bottom structure along a planned pipeline, is a good tool to demonstrate the way how to prepare and to carry out exploration of raw materials on the sea bottom, using acoustic methods.
PL
Przedstawiono możliwości dokładnego rozpoznania i kartometrycznego obrazowania dna w relacji do określania zasobów kruszyw mineralnych, z zastosowaniem zintegrowanego systemu nowoczesnych metod bezinwazyjnych. Stosowano zdjęcie dna echosondą wielowiązkową i sonarem bocznym, profilowanie sejsmiczne profilografem osadów, przegląd dna systemem telewizji podwodnej, pomiary magnetometrem. Wszystkie dane były zbierane i opracowywane przy dokładności pozycjonowania lepszej niż 0,2 m, prowadzonej w czasie niemal rzeczywistym. Przedstawione przykłady pochodzą z przygotowywanego do eksploatacji pola kruszywa w Zatoce Koszalińskiej. Uzyskiwane rezultaty dobitnie wskazują na konieczność odpowiedniego uwzględnienia użycia przedstawianych metod w odnośnych przepisach związanych z poszukiwaniem, rozpoznawaniem eksploatacją i monitoringiem złóż występujących na dnie morskim. Zdaniem autorów pierwszym etapem tych prac winno być obowiązkowe wykonanie pomiaru echosondą wielowiązkową a dalsze etapy zależeć będą od uzyskanego obrazu dna. Opracowania wykonane bez zdj ęcia echosondą wielowiązkową są niewiarygodne.
EN
The effects of the application of modern, integrated non-invasive measuring system to detailed recognition and mapping of the sea bottom in relation to determination of the mineral aggregates are presented. The bottom images obtained by Multibeam Echosounder and Side-Scan Sonar, seismic profiling by Subbottom Profiler, bottom inspection by underwater TV ROV system and magnetometer measurements were used. All data were collected and elaborated with precise positioning system, with precision better than 0.2 m, in nearly real time. Presented examples are situated within sandy/gravelly exploitation field in the Bay of Koszalin. The obtained results demonstrate the necessity to strongly demand the use of the adequate methods in regulations concerning exploration, exploitation and monitoring of the resources on the sea bottom. According to authors the first stage of the work must be to obtain bottom images by Multibeam Echosounder. The next stages will depend on the obtained bottom shape. The studies and measurements realized without Multibeam Echosounder images are not credible.
EN
In the paper we propose the method of seabed morphological features extraction, which we have obtained from bathymetric and backscatter data, recorded by multibeam echosounder. Presented results of acoustical recognition of the southern Baltic Sea bottom are the part of measurements conducted in the band of 220 km length in the central part of Polish coastal water. The detailed analysis of seabed features were performed for area located in the vicinity of Kołobrzeg harbour. The degree of seafloor corrugation was determined by autocorrelation analysis of seafloor bathymetry. To which, we used estimation of autocorrelation length and fractal dimension, based on the shape of autocorrelation function. Moreover, the parameters of wavelet decomposition of bottom backscattering strength were the input to fuzzy logic clustering system allowing for outline of seafloor areas of similar morphological features. Both presented methods have confirmed its effectiveness in identifying morphological characteristics and types of the bottom surface.
EN
The paper presents methodology for determination of areas suitable for high power offshore wind farms in the Polish Exclusive Economic Zone of the Baltic Sea. Possible conflicts between different sea users and ways of their minimization are considered, especially in the aspect of navigation.
EN
This paper summarises current knowledge of goods and services in the Polish Exclusive Economic Zone of the Baltic Sea ecosystem. It reviews specific properties of the Baltic that could be used for economic valuation. Goods and services range from the familiar resources of fish and minerals, which were valued with the Productivity Method, to less obvious services provided by the ecosystem such as biofiltration in coastal sands, valued with either the Replacement Cost or Damage Cost Avoided methods. Disservices to the marine ecosystem are also considered, e.g. erosion and coastal flooding, including the costs of planned mitigating measures. This paper emphasises the importance of using valuation methods to help make better-educated decisions for the sustainability of the Baltic Sea.
EN
Water level 48-hour forecast data for the Pomeranian Bay, obtained from the operational model "HIROMB", have been compared with the coastal water level records. The gauges of Mrzeżyno, Dziwnów, Koserów and Sassnitz as well as 0-24 hours and 24-48 hours forecast for the appropriate grid nodes have been analysed. An overview of different statistical criteria has been done. The statistical analysis has shown a satisfactory agreement between the forecast and observed data. However, the problem of the common reference level for the all gauges remains still unsolved.
EN
The paper presents results of comparison of the numerical weather forecast data from two models (UMPL - ICM, Warsaw University and HIRLAM - SMHI Norrköping) with the measurements made in 2000 and 2001 at the open sea near the Hel Peninsula from the automatic buoy MIG-1. The agreement of both models with the experimental data is quite good.
EN
The following paper presents a comparison of water Level data taken during the POLRODEX'97 experiment by some Polish water Level gauges situated around the Gulf of Gdansk with results computed for this period using the High Resolution Operational Model for the Baltic Sea (HIROMB ). Additionally sea level changes near the oil-drilling platform BETA were computed using data from pressure sensors and compared with results of the model. It is found that observed and computed values of sea level change are in good agreement.
EN
The following presents a test of implementation of WAM- a third generation wind wave model for oceans, for computations of wave conditions on the Baltic Sea. This work presents an actual state of implementations of this model for existing in the Maritime Institute data base for bathymetry, input meteorological forces and computation possibilities, and point sout future potential of its development and implementation for operational forecasting. Special attention was given to areas near the Polish coast, where field experiments POLRODEX were performed. The computations were made for homogenous wind fields, as well as for wind fields connected with real meteorological situations.
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