10 Applications of the Inverse Problem of Pollution Propagation
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the net current-driven transport frequently has semi-persistent patterns on the surface (Soomere et al. 2011d; Lu et al. 2012) or in the subsurface layer (Andrejev
et al. 2004a, 2004b). These usually concealed patterns make the probability of transport of various substances between different sea areas highly variable. The resulting
current-driven transport may be at times directed across relatively narrow regions
(Soomere et al. 2011d) and/or may lead to unexpectedly high probability of transport of adverse impacts between certain regions (Lekien et al. 2003). The challenge
addressed here is how to quantify the impact of this transport in some commonly
usable and clearly understandable categories.
10.1.2 The Value of Different Sea Areas
This challenge is only meaningful if some value is assigned to certain regions. The
difference in the value of various offshore and nearshore domains was recognized
many centuries ago (Bowden-Kerby 2001). It is legally formulated in the recent past
through establishing marine protected areas and developing the concept of particularly sensitive sea areas (Kachel 2008). Giving some regions a certain value naturally generates a spatio-temporal distribution of costs of consequences. Namely,
similar accidents but occurring at different locations usually impact the valuable
areas differently.
This distribution obviously depends on the demarcation of the valuable areas and
on the assigned ‘price.’ For some cases (e.g., the collision with a whale, Stokstad
2009) the cost is evident immediately at the site and the use of its spatial distribution
(e.g., the frequency of observations of the whales) for environmental management is
straightforward. Still on many occasions a substantial part of the costs becomes evident later through some hidden or hardly predictable mechanism of remote impact.
Some of these situations (e.g., the propagation of an ash cloud after a volcano eruption) are out of the control of society. Many others (incl. ship accidents), however,
allow at least limited human control.
A generic example of a dangerous event with substantial remote impact, used in
this book to illustrate the developed technique, is an oil spill. It is obviously undesirable everywhere on the sea but the scale of the associated devastation drastically
increases when it drifts to some valuable area. It is not possible to control the wind,
waves or currents that govern the fate of an oil spill but it is viable to restrict, at least
to some extent, the location of the potential sources of oil spills.
If vulnerable spots are selected based on environmental criteria a smart use of
the factors that drive the oil propagation may provide a natural way to mitigate the
environmental damage. This chapter presents a technique for applying knowledge
of natural processes for this purpose and provides several examples about how to
use it for decision-making. An important step is the identification of areas of reduced risk, so that for accidents occurring there, the costs through current-driven
remote impact are lower than for adjacent areas. In many cases directing activities
to these areas involves marginal additional costs. A corresponding policy may serve
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the net current-driven transport frequently has semi-persistent patterns on the surface (Soomere et al. 2011d; Lu et al. 2012) or in the subsurface layer (Andrejev
et al. 2004a, 2004b). These usually concealed patterns make the probability of transport of various substances between different sea areas highly variable. The resulting
current-driven transport may be at times directed across relatively narrow regions
(Soomere et al. 2011d) and/or may lead to unexpectedly high probability of transport of adverse impacts between certain regions (Lekien et al. 2003). The challenge
addressed here is how to quantify the impact of this transport in some commonly
usable and clearly understandable categories.
10.1.2 The Value of Different Sea Areas
This challenge is only meaningful if some value is assigned to certain regions. The
difference in the value of various offshore and nearshore domains was recognized
many centuries ago (Bowden-Kerby 2001). It is legally formulated in the recent past
through establishing marine protected areas and developing the concept of particularly sensitive sea areas (Kachel 2008). Giving some regions a certain value naturally generates a spatio-temporal distribution of costs of consequences. Namely,
similar accidents but occurring at different locations usually impact the valuable
areas differently.
This distribution obviously depends on the demarcation of the valuable areas and
on the assigned ‘price.’ For some cases (e.g., the collision with a whale, Stokstad
2009) the cost is evident immediately at the site and the use of its spatial distribution
(e.g., the frequency of observations of the whales) for environmental management is
straightforward. Still on many occasions a substantial part of the costs becomes evident later through some hidden or hardly predictable mechanism of remote impact.
Some of these situations (e.g., the propagation of an ash cloud after a volcano eruption) are out of the control of society. Many others (incl. ship accidents), however,
allow at least limited human control.
A generic example of a dangerous event with substantial remote impact, used in
this book to illustrate the developed technique, is an oil spill. It is obviously undesirable everywhere on the sea but the scale of the associated devastation drastically
increases when it drifts to some valuable area. It is not possible to control the wind,
waves or currents that govern the fate of an oil spill but it is viable to restrict, at least
to some extent, the location of the potential sources of oil spills.
If vulnerable spots are selected based on environmental criteria a smart use of
the factors that drive the oil propagation may provide a natural way to mitigate the
environmental damage. This chapter presents a technique for applying knowledge
of natural processes for this purpose and provides several examples about how to
use it for decision-making. An important step is the identification of areas of reduced risk, so that for accidents occurring there, the costs through current-driven
remote impact are lower than for adjacent areas. In many cases directing activities
to these areas involves marginal additional costs. A corresponding policy may serve