Emissions
of aerosol particles
CC-7
Climate
Change
Pressure
1 Indicator
definition and unit of measurement
Total
emissions of aerosol particles. The indicator includes primary aerosols (such
as industrial, soot from fossil fuels and soot from biomass combustion) and
secondary aerosols (such as sulphates from SO
2
emissions, organic aerosols from biomass burning, and nitrates from NO
x).
Natural emissions from e.g. volcanic eruptions are not accounted for in this
indicator. The unit of measurement is tonnes of aerosol particles per year.
2 Placement
in the framework
5EAP:
Chapter
5: The themes and targets of the programme, section 5.1: Climate change and
section 5.2: Acidification and air quality.
Agenda
21:
Chapter
9: Protection of the atmosphere, section 2: Conservation and management of
resources for development.
International
conventions and agreements:
The
UNECE LRTAP (Geneva, 1997) and its 1985 Helsinki Protocol on the Reduction of
Sulphur Emissions, its 1994 Oslo Protocol on Further Reduction of Sulphur
Emissions, and its 1988 Sofia Protocol concerning the Control of Emissions of
Nitrogen Oxides. The preparation of a new protocol is initiated on nitrogen
compounds and related substances.
Proposal
for a Council decision on the conclusion by the EC of the Protocol to the LRTAP
on further reduction of sulphur emissions (COM(97)88) is under discussion with
Member States (Directive to enter into force by 1.6.98).
Ranking:
Core
ranking:
7
(23%)
Policy
Relevance:
11
(2.5)
Analytical
Soundness:
10
(2.6)
Responsiveness:
8
(2.6)
Most
appropriate related state indicator:
Concentrations
of aerosol particles, global temperature.
3 Significance
Purpose:
Aerosol
particles cool the climate in two ways: directly by scattering and absorbing
radiation, and indirectly by providing seeds for cloud formation. The main
purpose of this indicator is to monitor total emissions of aerosol particles.
Relevance:
The
policy relevance of an indicator for aerosol particles is very limited.
Negative effects, such as acidification and effects on human health, justify
policies to reduce these emissions.
Linkages
to other pressure indicators:
The
indicator is linked with those in the area of Climate Change, specifically with
the indicators for SO
x
(CC-6)
and NOx emissions (CC-5). It is also linked with the policy fields Air
Pollution and Urban Environmental Problems. See the corresponding methodology
sheets (AP-1, AP-4 and UP-9).
Targets:
For
SO
2
emissions, the EU target is a 35% reduction in 2000 (1985 level); for NO
x
emissions a stabilisation in 1994 (1990 level) and a 30% reduction in 2000.
4 Methodological
description and underlying definitions
Underlying
definitions and concepts:
This
indicator is an aggregated indicator, including among others SO
2
emissions as the main source for sulphate aerosols. See the methodology sheet
for “SO
x
emissions”.
Measurement
methods:
The
1996 "Guidelines for National Greenhouse Gas Inventories” include SO
2
and NO
x
emissions. A more detailed methodology can be found in the joint EMEP/CORINAIR
(1996) “Atmospheric Emission Inventory Guidebook”.
Limitations
of the indicator:
Weighting
factors to aggregate the various emissions of aerosols are very difficult to
determine. Firstly, the cooling effects of the various types of aerosols are
difficult to quantify. Secondly, effects of combinations of aerosols are not
simply the addition of the effects of individual types of aerosols. Moreover,
emission estimates for aerosols (besides NO
x
and SO
2
emission estimates) will be hardly available. For further limitations, see the
methodology sheet for “SO
x
emissions” in this section.
Alternative
definitions:
Individual
indicators for various types of aerosol particles.
