Geoscience Reference
In-Depth Information
the different levels of pollutants present on a daily basis. The spatialization of air
quality is paradoxical for an element which crosses the boundaries [ROU 01b].
The spatialization of air quality assumes that three phases take place. The first
phase is inventory a list of sources, as well as working out the spatialization of the
sources; the second phase involves plotting the air quality measurements on a map;
and the final phase involves linking atmospheric pollution with other geocoded data
so that it is possible to evaluate the exposure to pollution and the health risks
associated with this.
Developing tools that can be adapted to these three different phases of
spatialized atmospheric pollution leads to the creation of some major
methodological problems. These problems correspond to the superposition of three
different models. One model is used for the spatialization of emissions, whilst
another converts emissions to immissions, which is made possible by integrating the
difficulties associated with mapping the climate into the model. The remaining
model, which is used to measure the spatialization of risks associated with
atmospheric pollution, shows that on a local scale it is still quite difficult to measure
how much exposure the population has had to atmospheric pollution. The
superposition of these three approaches leads to the creation of different problems
for each of the different models.
6.3.1.
A spatialized emissions inventory
If the different pollutants are able to move from country to country and if the
sources of pollution are found at a local level, this means that the different sources
need to be identified and included in an emission inventory that is created and
provides information on the different emitting sources that send pollutants into the
atmosphere. These documents, which are created for each pollutant, incorporate the
quantities of gas that are emitted by a surface unit whose size is fixed and whose
size depends on the area under investigation. The creation of these inventories
questions the spatialization of data, and the ventilation of a specific piece of
information which can be found in a particular spatial unit. Martinet [MAR 04]
based his thesis on these methodological issues. How may the emissions coming
from one factory chimney be affected in different spatial units? The spatialized
emissions inventories are essential tools that can be used to model and map air
quality. They are also tools that can be used to examine whether the pollution level
is decreasing/increasing. When these tools are used for greenhouse gases, they can
help decrease greenhouse gas emissions by a factor of four. Therefore, it is
necessary that the methodologies adopted for creating such inventories all over
Europe are uniform, and that these inventories are scientifically tested and verified.
With the use of its Corin-air data, the European Union is developing a coherent set
of European inventories and is working on harmonizing the different emission
factors that are included in these inventories. In France, the Technical
