22
T. Soomere
Since the entire Baltic Sea is too large to reproduce the currents with the necessary accuracy, we specifically concentrate on two target regions: the Gulf of Finland
and the south-western Baltic Sea. The former is the most vulnerable area hosting
extremely heavy ship and tanker traffic (Kujala et al. 2009), and the busiest port,
namely Saint Petersburg with >14,500 ship visits per year. Moreover, the spatial
distribution of the probability of ship accidents has been quantified in great detail
for this area (Goerlandt and Kujala 2011). The Belt Sea and the Arkona Basin in the
south-western Baltic Sea are the areas where all the ships travelling into/from the
North Sea have to pass through.
Stressing the generic character of the reasoning, we shall use the Baltic Sea not
only as an example for explaining the concept but also as an area where innovative
solutions are urgently needed, and where the proposed technology is expected to
work. For this reason, we start with a detailed overview of the Baltic Sea as the
target area for which the technique has been developed (Chap. 2). This overview
focuses on the basic features of the dynamics of currents and the requirements for
their modelling.
A successful implementation of the entire technology requires excellent competence in circulation modelling for the target area. There exist a variety of different
models, from greatly simplified toy models reproducing the basic flow features up to
highly sophisticated modelling systems. For making a good choice among different
models for a particular target area it is advisable to have an extended understanding
about how such models work, what their strong and weak points are and, most importantly, what they can and what they cannot describe. This subject is covered by a
generic introduction into principles of ocean modelling (Chap. 3) and by an in-depth
insight into the challenges of circulation modelling in the Baltic Sea (Chap. 4). In
particular, Chap. 4 describes the outcome of a complementary application of the Eulerian transport for the optimization of the fairways with respect to coastal pollution
in the Baltic Proper.
This material is complemented by a comprehensive overview of specific features
of other major European seas and inside information about the requirements and
potential pitfalls in their modelling (Chap. 5). The potential of the use of this method
for both ‘ideal’ persistent pollution particles and for more realistic behaviour of oil
spills will be demonstrated in the context of the optimization of ship routes in the
Gulf of Finland in terms of minimizing the risk of coastal pollution. Chapter 6 gives
an insight into the richness of the dynamics of this basin and a number of interesting
features that make this area challenging for modellers.
The second key component of the technology, the art of modelling of Lagrangian
trajectories of selected particles based on precomputed Eulerian velocity fields, is introduced in Chap. 7. The modelling procedure is exemplified using the open-source
TRACMASS code. Our research has highlighted an essential difference between the
Lagrangian and Eulerian transport in the Baltic Sea (Chap. 8). This feature leads to
the necessity of a specific tuning of the modelled Lagrangian trajectories for certain
sea areas in order to properly represent the statistics of oil spill propagation. Along
with an essential collection of very recent experimentally measured subsurface drift
T. Soomere
Since the entire Baltic Sea is too large to reproduce the currents with the necessary accuracy, we specifically concentrate on two target regions: the Gulf of Finland
and the south-western Baltic Sea. The former is the most vulnerable area hosting
extremely heavy ship and tanker traffic (Kujala et al. 2009), and the busiest port,
namely Saint Petersburg with >14,500 ship visits per year. Moreover, the spatial
distribution of the probability of ship accidents has been quantified in great detail
for this area (Goerlandt and Kujala 2011). The Belt Sea and the Arkona Basin in the
south-western Baltic Sea are the areas where all the ships travelling into/from the
North Sea have to pass through.
Stressing the generic character of the reasoning, we shall use the Baltic Sea not
only as an example for explaining the concept but also as an area where innovative
solutions are urgently needed, and where the proposed technology is expected to
work. For this reason, we start with a detailed overview of the Baltic Sea as the
target area for which the technique has been developed (Chap. 2). This overview
focuses on the basic features of the dynamics of currents and the requirements for
their modelling.
A successful implementation of the entire technology requires excellent competence in circulation modelling for the target area. There exist a variety of different
models, from greatly simplified toy models reproducing the basic flow features up to
highly sophisticated modelling systems. For making a good choice among different
models for a particular target area it is advisable to have an extended understanding
about how such models work, what their strong and weak points are and, most importantly, what they can and what they cannot describe. This subject is covered by a
generic introduction into principles of ocean modelling (Chap. 3) and by an in-depth
insight into the challenges of circulation modelling in the Baltic Sea (Chap. 4). In
particular, Chap. 4 describes the outcome of a complementary application of the Eulerian transport for the optimization of the fairways with respect to coastal pollution
in the Baltic Proper.
This material is complemented by a comprehensive overview of specific features
of other major European seas and inside information about the requirements and
potential pitfalls in their modelling (Chap. 5). The potential of the use of this method
for both ‘ideal’ persistent pollution particles and for more realistic behaviour of oil
spills will be demonstrated in the context of the optimization of ship routes in the
Gulf of Finland in terms of minimizing the risk of coastal pollution. Chapter 6 gives
an insight into the richness of the dynamics of this basin and a number of interesting
features that make this area challenging for modellers.
The second key component of the technology, the art of modelling of Lagrangian
trajectories of selected particles based on precomputed Eulerian velocity fields, is introduced in Chap. 7. The modelling procedure is exemplified using the open-source
TRACMASS code. Our research has highlighted an essential difference between the
Lagrangian and Eulerian transport in the Baltic Sea (Chap. 8). This feature leads to
the necessity of a specific tuning of the modelled Lagrangian trajectories for certain
sea areas in order to properly represent the statistics of oil spill propagation. Along
with an essential collection of very recent experimentally measured subsurface drift