The Knudsen theorem and the Total Exchange Flow analysis framework applied to the Baltic Sea

2018 ◽  
Vol 165 ◽  
pp. 268-286 ◽  
Author(s):  
Hans Burchard ◽  
Karsten Bolding ◽  
Rainer Feistel ◽  
Ulf Gräwe ◽  
Knut Klingbeil ◽  
...  
Ocean Science ◽  
2019 ◽  
Vol 15 (3) ◽  
pp. 601-614 ◽  
Author(s):  
Marvin Lorenz ◽  
Knut Klingbeil ◽  
Parker MacCready ◽  
Hans Burchard

Abstract. For more than a century, estuarine exchange flow has been quantified by means of the Knudsen relations which connect bulk quantities such as inflow and outflow volume fluxes and salinities. These relations are closely linked to estuarine mixing. The recently developed Total Exchange Flow (TEF) analysis framework, which uses salinity coordinates to calculate these bulk quantities, allows an exact formulation of the Knudsen relations in realistic cases. There are however numerical issues, since the original method does not converge to the TEF bulk values for an increasing number of salinity classes. In the present study, this problem is investigated and the method of dividing salinities, described by MacCready et al. (2018), is mathematically introduced. A challenging yet compact analytical scenario for a well-mixed estuarine exchange flow is investigated for both methods, showing the proper convergence of the dividing salinity method. Furthermore, the dividing salinity method is applied to model results of the Baltic Sea to demonstrate the analysis of realistic exchange flows and exchange flows with more than two layers.


2019 ◽  
Author(s):  
Marvin Lorenz ◽  
Knut Klingbeil ◽  
Parker MacCready ◽  
Hans Burchard

Abstract. For more than a century, estuarine exchange flow has been quantified by means of the Knudsen relations which connect bulk quantities such as inflow and outflow volume fluxes and salinities. These relations are closely linked to estuarine mixing. The recently developed Total Exchange flow (TEF) which uses salinity coordinates to calculate these bulk quantities allows an exact formulation of the Knudsen relations in realistic cases. There are however numerical issues, since the original method does not converge to the TEF bulk values for an increasing number of salinity classes. In the present study, this problem is investigated and the method of dividing salinities, described by MacCready et al. (2018), is mathematically introduced. A challenging yet compact analytical scenario for a well-mixed estuarine exchange flow is investigated for both methods, showing the proper convergence of the dividing salinity method. Furthermore, the dividing salinity method is applied to model results of the Baltic Sea to demonstrate the analysis of realistic exchange flows and exchange flows with more than two layers.


Author(s):  
Magda Wilewska-Bien ◽  
Lena Granhag ◽  
Jukka-Pekka Jalkanen ◽  
Lasse Johansson ◽  
Karin Andersson

Material flow analysis is used to identify and quantify the flow of phosphorus (P) in ship-generated food waste and wastewater. Passenger, cruise, RoPax and cargo ships in the Baltic Sea were investigated in three scenarios: (1) if all waste is discharged to sea, (2) if all waste is disposed of ashore or (3) if the food waste fraction is disposed of ashore and wastewater is treated on-board. About 107 tonnes of P is generated annually in the waste streams, with highest contribution of approximately 62 tonnes (58%) from wastewater in the ship-category RoPax. Approximately 24 tonnes of P is contained in the food waste generated by the ships in the study. Forthcoming regulations over allowed nutrient concentrations in sewage will lead to 80% reduction in P from passenger ships and can reduce about 31 tonnes of P entering the Baltic Sea environment. If both sewage and grey water instead are offloaded in port reception facilities, about 76 tonnes of P-reduction to the sea can be reached. As most phosphorus recovery practices currently only are available on land it is recommended to direct the waste streams to port reception facilities for further treatment ashore.


2016 ◽  
Vol 17 (4) ◽  
pp. 335-349
Author(s):  
Andrius Jarzemskis ◽  
Ilona Jarzemskiene

Abstract Baltic Marine Environment Protection Commission members seeking to implement MARPOL 73/78 Annex IV amendments which recognize the Baltic Sea as special are, in which discharge of uncommitted sewage from passenger ships is forbidden, must ensure that ports are equipped with adequate reception facilities. To ensure implementation of amendments of Annex IV in port of Klaipeda, the analysis framework model was defined by authors. The model evaluates the readiness of the port to changes brought by the amendments of MARPOL Annex IV. The scientific problem comes with perception of adequacy. Resolution MEPC.200(62) amending MARPOL 73/78 Annex IV states, that port reception facilities must be adequate to the needs of passenger ships using them without causing undue delay. Concept of adequacy is not defined, therefore other guidelines explaining adequacy were used: EU directive 2000/59/EC and IMO resolution MEPC.83(44) Guidelines for ensuring adequacy of port reception facilities. Based on these sources, criteria that must be met to ensure adequacy were identified and tested in article: 1) reception facilities meet needs of ships normally using them; 2) discharge of sewage does to cause undue delay; 3) reception facilities does not provide disincentive to use them; 4) facilities are accessible; 5) facilities contribute to the improvement of the marine environment.


Boreas ◽  
2002 ◽  
Vol 31 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Christian Christiansen ◽  
Helmar Kunzendorf ◽  
Kay-Christian Emeis ◽  
Rudolf Endler ◽  
Ulrich Struck ◽  
...  

2003 ◽  
pp. 136-146
Author(s):  
K. Liuhto

Statistical data on reserves, production and exports of Russian oil are provided in the article. The author pays special attention to the expansion of opportunities of sea oil transportation by construction of new oil terminals in the North-West of the country and first of all the largest terminal in Murmansk. In his opinion, one of the main problems in this sphere is prevention of ecological accidents in the process of oil transportation through the Baltic sea ports.


Author(s):  
Angelina E. Shatalova ◽  
Uriy A. Kublitsky ◽  
Dmitry A. Subetto ◽  
Anna V. Ludikova ◽  
Alar Rosentau ◽  
...  

The study of paleogeography of lakes is an actual and important direction in modern science. As part of the study of lakes in the North-West of the Karelian Isthmus, this analysis will establish the dynamics of salinity of objects, which will allow to reconstruct changes in the level of the Baltic Sea in the Holocene.


Author(s):  
Małgorzata Leśniewska ◽  
Małgorzata Witak

Holocene diatom biostratigraphy of the SW Gulf of Gdańsk, Southern Baltic Sea (part III)The palaeoenvironmental changes of the south-western part of the Gulf of Gdańsk during the last 8,000 years, with reference to the stages of the Baltic Sea, were reconstructed. Diatom analyses of two cores taken from the shallower and deeper parts of the basin enabled the conclusion to be drawn that the microflora studied developed in the three Baltic phases: Mastogloia, Littorina and Post-Littorina. Moreover, the so-called anthropogenic assemblage was observed in subbottom sediments of the study area.


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