Baltic Sea Typology Editors

This article is an update and extension of an earlier publication (SCHERNEWSKI & WIELGAT 2004). Intensive public discussions suggested slight modifications in the typology as well as an updating and completion of comparisons between our typology and the national typologies. We further show examples how the water body concept can be applied to subdivide coastal water types as a response to external pressures. The water body concept allows a kind of subdivision of the typology e.g. in river plumes or near emission sources of pollutants. The Water Framework Directive (WFD) establishes a comprehensive framework for European Community actions in the field of water and introduces new principles of modern water management. New is especially the spatial integration of river basins, coastal and coastal waters as well as the focus on biological ecosystem quality elements. The WFD requires from all EU Member States to protect and enhance the status of water quality of all types of waters, including coastal zone of the sea. For the purpose of the WFD implementation all water bodies must be classified into types of similar characteristics based on the physical factors. This classification scheme is called typology and forms a universal basis for all other activities within the WFD implementation such as: management or monitoring. The implementation of the WFD as well as the development of a national typology are a responsibility of national authorities and are due to be operational in a few years time. As a result, every country develops or has already developed an independent typology. The WFD defines the Baltic Sea as one Ecoregion. The coastal waters have an international character but national typologies will cause interceptions at country borders and different national typologies will complicate large scale comparisons across the Baltic Sea. Further, the definition of coastal waters (1 nm off the baseline) is artificial. The division between coastal waters and open waters is not in agreement with morphological, physical, chemical or biological parameters. Therefore, a joint typology approach, not only for the Baltic coastal waters, but the entire Baltic Sea is needed. Within the EU-project CHARM (Characterization of the Baltic Sea Ecosystem) a joint Baltic Sea typology was developed. The suggestion in the EU-CIS Working Group 2.4 Guidance Document formed the basis. Salinity was used as the main obligatory factor. For the Baltic Sea typology residence time and depth/mixing conditions were additionally used. The typology is not meant to replace national typologies. It is developed as an umbrella, which allows the integration of the national typologies and a further subdivision according to regional demands. It therefore serves as a link or an integrative element for the national typologies. The Baltic Sea typology covers the entire Baltic Sea and is not limited to the definition area of the Water Framework Directive.