Emissions
of methyl bromide (CH3Br)
OD-7
Ozone
Depletion
Pressure
1 Indicator
definition and unit of measurement
Total
emissions of methyl bromide (CH
3Br),
Montreal Protocol Annex E, Group I. Emissions of methyl bromide are for
comparison reasons multiplied with its Ozone Depletion Potential
[22].
The unit of measurement is therefore tonnes of total CFC-11 emissions per year
(CFC-11 is reference).
2 Placement
in the framework
5EAP:
Chapter
4: The themes and targets of the programme, section 5.1: Climate change.
Agenda
21:
Chapter
9: Protection of the atmosphere.
International
conventions and agreements:
Methyl
bromide is included in the 1997 (Montreal, 15-17. Sept.), 1992 (Copenhagen) and
1995 (Vienna) Amendments and Adjustments to the Montreal Protocol (1987).
Council Regulation (EC) N° 3093/94 of 15.12.94 on substances that deplete
the ozone layer (OJ N° L333, 22.12.94, p.1).
Ranking:
Core
ranking:
7
(29%)
Policy
Relevance:
5
(2.7)
Analytical
Soundness:
6
(2.4)
Responsiveness:
9
(2.5)
Most
appropriate related state indicator:
Changes
in concentrations of stratospheric ozone.
3 Significance
Purpose:
Methyl
bromide continues to be viewed as a significant ozone-depleting compound. The
main purpose of this indicator is to monitor total anthropogenic emissions of
methyl bromide (CH
3Br).
Relevance:
Methyl
bromide is a major anthropogenic source gas for stratospheric bromine. Bromine
is estimated to be about 50 times more efficient than chlorine in destroying
stratospheric ozone. See also 3. Relevance of the methodology sheet of halons.
Linkages
to other pressure indicators:
The
indicator is linked to the indicators of other ozone depleting substances.
Furthermore, the indicator is linked with those in the area of Climate Change.
See also 3. Linkages to other pressure indicators of the methodology sheet of
halons.
Targets:
The
Montreal agreement proposes that developed countries shall undertake to phase
out the use of methyl bromide by the year 2005, with a gradual reduction of 25%
in 1999, 50% in 2001 and 70% in 2003. The standards originally recommended
sought a total phase-out of the substance by 2010 with a 25% reduction in 2001
and 50% in 2005.
4 Methodological
description and underlying definitions
Underlying
definitions and concepts:
Three
potentially major anthropogenic sources of methyl bromide have been identified:
1. soil fumigation, 2. biomass burning, 3. exhaust of automobiles using leaded
gasoline. The oceans are a major natural source of methyl bromide. Natural
emissions are not accounted for in this indicator.
Measurement
methods:
Emissions
can be estimated based on the accounting of annual net consumption.
Limitations
of the indicator:
Emissions
are hard to estimate.
Alternative
definitions:
None.
[22]
Ozone
Depletion Potentials:
CFC-11
= 1.0 (Reference)
CH3Br
= 0.7
