Chapter 5
European Semi-enclosed Seas: Basic Physical
Processes and Their Numerical Modelling
Emil V. Stanev and Xi Lu
Abstract A parallel analysis of the physical state of European semi-enclosed seas,
namely the Black Sea, Baltic Sea and Mediterranean Sea, is presented based on
observations and numerical modelling, with the aim of revealing similarities and
differences between the dominating physical processes. Each of the three basins
is presented in more detail with respect to processes which are very specific and
relatively well studied: the formation of intermediate water masses in the Black
Sea, strait exchange and circulation in the transition area between the Baltic and
North Sea, and deep water formation and the Eastern Mediterranean Transient. For
the three basins extended discussions on the strait exchanges, the routing of deep
inflows by straits, and underwater passage channels and shallows are provided. It is
demonstrated that although the topographic routing has very different appearances
in the three basins, in general it strongly controls the formation of water masses
and thermohaline circulation. This review aims also at motivating parallel studies on
similar geophysical systems and sharing of specific or common experiences between
researchers dealing with the individual European seas.
5.1 Introduction
The difference in the net water budget of semi-enclosed seas P + R − E expressed
as precipitation P plus river inflow R minus evaporation E results in different water
regimes in individual basins. Depending on the sign of the water budget, basins are
known to be of dilution (estuarine) type if P + R − E > 0, and of concentration
(lagoon) type if P + R − E < 0. In Europe there are two typical semi-enclosed estuarine basins, the Black Sea and the Baltic Sea, and one concentration basin, the
Mediterranean Sea (Fig. 5.1). These seas provide paradigms of semi-enclosed seas
E.V. Stanev (B) · X. Lu
Institute for Coastal Research, Helmholz Zentrum Geesthacht, Max-Planck-Strasse 1,
21502 Geesthacht, Germany
e-mail: stanev@hzg.de
X. Lu
e-mail: xi.lu@hzg.de
T. Soomere, E. Quak (eds.), Preventive Methods for Coastal Protection,
DOI 10.1007/978-3-319-00440-2_5,
© Springer International Publishing Switzerland 2013
131
European Semi-enclosed Seas: Basic Physical
Processes and Their Numerical Modelling
Emil V. Stanev and Xi Lu
Abstract A parallel analysis of the physical state of European semi-enclosed seas,
namely the Black Sea, Baltic Sea and Mediterranean Sea, is presented based on
observations and numerical modelling, with the aim of revealing similarities and
differences between the dominating physical processes. Each of the three basins
is presented in more detail with respect to processes which are very specific and
relatively well studied: the formation of intermediate water masses in the Black
Sea, strait exchange and circulation in the transition area between the Baltic and
North Sea, and deep water formation and the Eastern Mediterranean Transient. For
the three basins extended discussions on the strait exchanges, the routing of deep
inflows by straits, and underwater passage channels and shallows are provided. It is
demonstrated that although the topographic routing has very different appearances
in the three basins, in general it strongly controls the formation of water masses
and thermohaline circulation. This review aims also at motivating parallel studies on
similar geophysical systems and sharing of specific or common experiences between
researchers dealing with the individual European seas.
5.1 Introduction
The difference in the net water budget of semi-enclosed seas P + R − E expressed
as precipitation P plus river inflow R minus evaporation E results in different water
regimes in individual basins. Depending on the sign of the water budget, basins are
known to be of dilution (estuarine) type if P + R − E > 0, and of concentration
(lagoon) type if P + R − E < 0. In Europe there are two typical semi-enclosed estuarine basins, the Black Sea and the Baltic Sea, and one concentration basin, the
Mediterranean Sea (Fig. 5.1). These seas provide paradigms of semi-enclosed seas
E.V. Stanev (B) · X. Lu
Institute for Coastal Research, Helmholz Zentrum Geesthacht, Max-Planck-Strasse 1,
21502 Geesthacht, Germany
e-mail: stanev@hzg.de
X. Lu
e-mail: xi.lu@hzg.de
T. Soomere, E. Quak (eds.), Preventive Methods for Coastal Protection,
DOI 10.1007/978-3-319-00440-2_5,
© Springer International Publishing Switzerland 2013
131