Chemistry Reference
In-Depth Information
Natural reasons
cover
1. The topographic and climatic situation, which triggers (adverse) dispersion
conditions, atmospheric chemistry and the possible contribution of long-range
transport
2. Natural sources (deductible in the air quality assessment)
Anthropogenic reasons
can be subdivided into
1. Emissions
2. The administrative, legal and political capacity for air quality management
Air quality management covers both national as well as international
obligations. From the position of a single Member State, transboundary pollution
can be seen as an “
external reason
”. Transboundary pollution is tackled e.g. by
the NEC Directive [
2
] and the UNECE protocols. However, the implementation
of these obligations is also a national task.
Some emission categories are interlinked with climatic factors, e.g. emissions
from domestic heating, from winter sanding or salting of roads. Therefore, a strict
separation of natural and anthropogenic reasons is not possible.
Emissions
are discussed with respect to (high) emission densities (related to area
or population), but also considered as a result of long-lasting policies and societal
developments.
Non-critical areas are those with partly similar conditions - e.g. adverse climatic
conditions, population density and emissions in previous time periods - but where
air quality problems have been dealt with successfully already or will be addressed
in the near future.
3 Datasets and Data Sources Used
In order to identify critical areas according to the methodology described below
different sources of information have been used.
These include:
• Datasets describing natural reasons for criticality:
- Climatic conditions (natural)
- Topography (natural)
- Land cover (partly natural, partly anthropogenic)
- Natural sources
• Datasets describing anthropogenic reasons for criticality:
- Emission data
- Population density
- Resulting pollutant levels (air quality and air quality trends)
- Transboundary contributions (“
external
” from the point of view of a
single MS)
