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Trends in water quality variations in the Odra River the day before implementation of the Water Framework Directive 总被引：1，自引：0，他引：1
This paper contains an account of UN/EEC-sponsored research on water quality monitoring and assessments in the catchments areas of Europe's 10 transboundary rivers. In this context, water quality assessments established on the basis of monitoring data for Poland's rivers are discussed. Consideration is also given to the water quality assessment methods recommended by the EU Directives. The problem has been exemplified by the analysis of water quality variations in the transboundary river Odra in the time span of 1973–2003. For the years 1993–2003, the trends in water quality variations are calculated and the rates of variation are analysed. The points in time when the water quality will have attained the second class purity values are predicted, taking into account the requirements specified in Polish, Czech and German standards. Analysis of the trends in the variations of pollution parameters has revealed that the achievability of good water quality depends on the limit values adopted for the assessment. 相似文献
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Forecast of storm surge by means of artificial neural network 总被引：1，自引：0，他引：1
Marzenna Sztobryn 《Journal of Sea Research》2003,49(4):317
This study describes the construction and verification of a model of sea level changes during a storm surge, applying artificial neural network (ANN) methodology in hydrological forecasting in a tideless sea where the variation of water level is only wind generated. Some neural networks were tested to create the forecast model. The results of ANN were compared with observed sea-level values, and with the forecasts calculated by different routine methods. The results of verification show that the neural network methodology could be successfully applied in the routine, operational forecast service. 相似文献
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Sztobryn Marzenna 《Oceanology》2012,52(6):741-747
The study focused on the evaluation of probable changes in the severity of sea ice conditions occurring in 3 selected areas of the Baltic Sea: the Gulf of Bothnia, Gulf of Finland and the Southern Baltic Sea up to the year 2100. The areas have been chosen due to the high intensity of marine traffic (the Gulfs??of Bothnia and of Finland) and due to differences in sea ice conditions; winters in the Gulf of Bothnia were characterized as the most severe, whereas in the Southern Baltic were classified as the mildest ones. Consequently, three scenarios were taken into account in the study: A2 (slow rate of global economic development, market scenario), A1B (regional scenario, rapid economic development, with ecological priorities), B1 (sustainable, median economic development with strong ecological priorities), all three constructed on the basis of Special Report on Emissions Scenarios (SRES models of greenhouse gas emission). The probable changes of sea ice conditions expressed as severity index S were calculated from these models. The main results of the investigation are as follows, the variety of sea ice conditions occurring in specific regions of the Baltic will remain stable (i.e. the most severe winter conditions will still occur in Gulf of Bothnia, while the mildest in the Southern Baltic Sea). The most significant changes are likely to occur in the Southern Baltic, where some winters without ice cover in the Vistula Lagoon may happen. Nonetheless, some extremely severe winters will occur and also within specific seasons more winters with a lower number of days with ice will occur. 相似文献
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