private stock directly, and household level heating system stock is poorly
known. Furthermore, spatial assessment (i.e. gridding) of residential combustion
activities is often uncertain because of the lack of building registers for residential heating appliances.
2.3.2 Pressures
Air pollutant emissions act as pressures on the environment. Thus, the block
PRESSURES of the IAM corresponds to the computation of the quantity of pollutants emitted into the atmosphere from stationary sources (such as smokestacks),
surface areas (commercial or industrial facilities), and mobile sources (for example,
road vehicles, locomotives, aircrafts, ships, etc.). The emission of a pollutant can in
general be measured (as in large point sources) or estimated. These are generally
calculated as the product of the activity of the emitter times an emission factor, that
is the quantity of pollutant emitted per unit of activity.
Other possible pressures that affect air pollution concentrations are related to
change of urban structures (new buildings, parks, etc.) that can modify the dispersion of the pollutants and so the concentrations. Similarly, strategies to mitigate
Urban Heat Island (white or green roofs, etc.) may also have an impact on concentrations without modifying the emissions. These structural modifications in the
city-level emission patterns are relevant, but at the moment very complex to be
incorporated into a IAM scheme, and so will not be considered in the following
descriptions.
Input
An emission is computed for a specific pollutant, an emission source, a spatial and
temporal resolution. An emission inventory is a database combining emissions with
a specific geographical area and time period (usually yearly-based) containing:
– The activity of the emission sources. For instance: the volume and the type of
fuel burned, the number of kilometres travelled by the vehicles, etc. The activity
data could be derived from (economic) statistics, including energy statistics and
balances, economic production rates, population data, etc.;
– The amount of pollutant emitted by these sources per unit of activity, i.e. the
emission factors.
The emission inventory may have different level of details depending on the
availability of the data and their uncertainties. Data could be given per each activity
sector, technology and fuel. For application of IAMs, information on costs and rates
of application of technologies has to be integrated (normally with the assumption
that costs remain linear with respect to rates of application).
The methodology used to estimate emissions depends on the objective of the
study, the availability of the data and their uncertainty. In case of lack of detailed
activity data or/and emission factors, it is necessary to collect such data at higher
20
N. Blond et al.
known. Furthermore, spatial assessment (i.e. gridding) of residential combustion
activities is often uncertain because of the lack of building registers for residential heating appliances.
2.3.2 Pressures
Air pollutant emissions act as pressures on the environment. Thus, the block
PRESSURES of the IAM corresponds to the computation of the quantity of pollutants emitted into the atmosphere from stationary sources (such as smokestacks),
surface areas (commercial or industrial facilities), and mobile sources (for example,
road vehicles, locomotives, aircrafts, ships, etc.). The emission of a pollutant can in
general be measured (as in large point sources) or estimated. These are generally
calculated as the product of the activity of the emitter times an emission factor, that
is the quantity of pollutant emitted per unit of activity.
Other possible pressures that affect air pollution concentrations are related to
change of urban structures (new buildings, parks, etc.) that can modify the dispersion of the pollutants and so the concentrations. Similarly, strategies to mitigate
Urban Heat Island (white or green roofs, etc.) may also have an impact on concentrations without modifying the emissions. These structural modifications in the
city-level emission patterns are relevant, but at the moment very complex to be
incorporated into a IAM scheme, and so will not be considered in the following
descriptions.
Input
An emission is computed for a specific pollutant, an emission source, a spatial and
temporal resolution. An emission inventory is a database combining emissions with
a specific geographical area and time period (usually yearly-based) containing:
– The activity of the emission sources. For instance: the volume and the type of
fuel burned, the number of kilometres travelled by the vehicles, etc. The activity
data could be derived from (economic) statistics, including energy statistics and
balances, economic production rates, population data, etc.;
– The amount of pollutant emitted by these sources per unit of activity, i.e. the
emission factors.
The emission inventory may have different level of details depending on the
availability of the data and their uncertainties. Data could be given per each activity
sector, technology and fuel. For application of IAMs, information on costs and rates
of application of technologies has to be integrated (normally with the assumption
that costs remain linear with respect to rates of application).
The methodology used to estimate emissions depends on the objective of the
study, the availability of the data and their uncertainty. In case of lack of detailed
activity data or/and emission factors, it is necessary to collect such data at higher
20
N. Blond et al.