Earth System Models (ESMs), with coupled
oceans, cryosphere, vegetation, and so on.
The Montreal Protocol has controlled the
major anthropogenic sources of chlorine and bromine which reach the stratosphere. However, a
current research area concerns natural sources of
similar halogen species. There is clear evidence
that around 6 parts per trillion (pptv) of the current
stratospheric bromine loading of 21 pptv comes
from sources other than CH 3 Br and the halons
[22]. The species responsible are the so-called
very short-lived species (VSLS) such as
bromoform (CHBr 3 ) and dibromomethane
(CH 2 Br 2 ). Although these species have atmospheric lifetimes of around 6 months or less,
they can still be transported to the stratosphere
[23]. These species are emitted naturally from
the oceans and it is possible that future climate
change will increase these emissions. This natural
source of halogens offsets some of the reduction
in anthropogenic halogens and leads to lower
levels of stratospheric ozone.
There is currently a large debate on the possibilities of avoiding climate change by human
manipulation of the climate system, so-called
geoengineering. Among the various potential
geoengineering solutions that have been proposed, one relates directly to the stratosphere.
Scientists have suggested that humans could replicate the effect of a large volcanic eruption which
injects sulfate aerosol directly into the stratosphere [24]. The most recent such large natural
eruption was Mt. Pinatubo in the Philippines in
June 1991. The impact of enhanced stratospheric
aerosol is to cool the surface – the desired effect
from a geoengineering point of view. However,
while atmospheric chlorine loadings remain high,
enhanced stratospheric aerosol will lead to ozone
destruction. The eruption of Mt. Pinatubo led to a
1–2% reduction in column ozone globally see (2).
As halogens decline in the future the impact of
aerosol on ozone will be less, as shown by simulations for the period of the large El Chichon
eruption in 1982, well before the peak in atmospheric chlorine and bromine [14]. The potential
side effects of such geoengineering options need
to be fully investigated and quantified with
detailed chemistry-climate models.
Bibliography
Primary Literature
1. Chapman S (1930) A theory of upper-atmosphere
ozone. Mem R Meteorol Soc 3:103
2. Crutzen PJ (1970) The influence of nitrogen oxide on
the atmospheric ozone content. Q J R Meteorol Soc
96:320
3. Johnston HS (1971) Reduction of stratospheric ozone
by nitrogen oxide catalysts from supersonic transport
exhaust. Science 173:517
4. Stolarski RS, Cicerone RJ (1974) Stratospheric chlorine: a possible sink for ozone. Can J Chem 52:1610
5. Molina MJ, Rowland FS (1974) Stratospheric sink for
chloro-fluoromethanes: chlorine atom catalysed
destruction of ozone. Nature 249:810–812
6. Farman JC, Gardiner BG, Shanklin JD (1985) Large
losses of total ozone in Antarctica reveal seasonal
ClOx/NOx interaction. Nature 315:207–210
7. Anderson JG, Brune WH, Proffitt MH (1989) Ozone
destruction by chlorine radicals within the Antarctic
vortex: the spatial and temporal evolution of ClO-O 3
anitcorrelation based on in situ ER-2 data. J Geophys
Res 94:11480–11520
8. Molina LT, Molina MJ (1987) Production of Cl 2 O 2 by
the self reaction of the ClO radical. J Phys Chem
91:433–436
9. Solomon S, Garcia RR, Rowland FS, Wuebbles
D (1986) On the depletion of Antarctic ozone. Nature
321:755–758
10. Chipperfield MP (2006) New version of the TOMCAT/SLIMCAT off-line chemical transport model:
intercomparison of stratospheric tracer experiments.
Q J R Meteorol Soc 132:1179–1203. https://doi.org/
10.1256/qj.05.51
11. Rex M, Salawitch RJ, von der Gathen P, Harris NRP,
Chipperfield MP, Naujokat B (2004) Arctic ozone loss
and climate change. Geophys Res Lett 31:L04116.
https://doi.org/10.1029/2003GL018844
12. Chipperfield MP, Fioletov V (Lead Authors)
(2007) Global Ozone. In: Ennis CA (ed) Scientific
assessment of ozone depletion, 2006: pursuant to Article 6 of Montreal Protocol on Substances that Deplete
the Ozone Layer, Chap 3. Global Ozone Research and
Monitoring Project – Report No. 50. World Meteorological Organization, Geneva, p 572
13. Chipperfield MP (1999) Multiannual simulations with
a threedimensional chemical transport model.
J Geophys Res 104:1781–1805
14. Tie XX, Brasseur GP (1995) The response of stratospheric ozone to volcanic eruptions: sensitivity to
atmospheric chlorine loading. Geophys Res Lett
22:3035–3038
15. Fahey DW (Lead Author) (2007) Twenty questions
and answers about the ozone layer: 2006 Update.
Scientific assessment of Ozone Depletion: 2006.
World Meteorological Organization, Geneva, p 50
16. United Nations Environment Program (UNEP)
(1998) Environmental effects of ozone depletion:
Stratospheric Pollution
381
oceans, cryosphere, vegetation, and so on.
The Montreal Protocol has controlled the
major anthropogenic sources of chlorine and bromine which reach the stratosphere. However, a
current research area concerns natural sources of
similar halogen species. There is clear evidence
that around 6 parts per trillion (pptv) of the current
stratospheric bromine loading of 21 pptv comes
from sources other than CH 3 Br and the halons
[22]. The species responsible are the so-called
very short-lived species (VSLS) such as
bromoform (CHBr 3 ) and dibromomethane
(CH 2 Br 2 ). Although these species have atmospheric lifetimes of around 6 months or less,
they can still be transported to the stratosphere
[23]. These species are emitted naturally from
the oceans and it is possible that future climate
change will increase these emissions. This natural
source of halogens offsets some of the reduction
in anthropogenic halogens and leads to lower
levels of stratospheric ozone.
There is currently a large debate on the possibilities of avoiding climate change by human
manipulation of the climate system, so-called
geoengineering. Among the various potential
geoengineering solutions that have been proposed, one relates directly to the stratosphere.
Scientists have suggested that humans could replicate the effect of a large volcanic eruption which
injects sulfate aerosol directly into the stratosphere [24]. The most recent such large natural
eruption was Mt. Pinatubo in the Philippines in
June 1991. The impact of enhanced stratospheric
aerosol is to cool the surface – the desired effect
from a geoengineering point of view. However,
while atmospheric chlorine loadings remain high,
enhanced stratospheric aerosol will lead to ozone
destruction. The eruption of Mt. Pinatubo led to a
1–2% reduction in column ozone globally see (2).
As halogens decline in the future the impact of
aerosol on ozone will be less, as shown by simulations for the period of the large El Chichon
eruption in 1982, well before the peak in atmospheric chlorine and bromine [14]. The potential
side effects of such geoengineering options need
to be fully investigated and quantified with
detailed chemistry-climate models.
Bibliography
Primary Literature
1. Chapman S (1930) A theory of upper-atmosphere
ozone. Mem R Meteorol Soc 3:103
2. Crutzen PJ (1970) The influence of nitrogen oxide on
the atmospheric ozone content. Q J R Meteorol Soc
96:320
3. Johnston HS (1971) Reduction of stratospheric ozone
by nitrogen oxide catalysts from supersonic transport
exhaust. Science 173:517
4. Stolarski RS, Cicerone RJ (1974) Stratospheric chlorine: a possible sink for ozone. Can J Chem 52:1610
5. Molina MJ, Rowland FS (1974) Stratospheric sink for
chloro-fluoromethanes: chlorine atom catalysed
destruction of ozone. Nature 249:810–812
6. Farman JC, Gardiner BG, Shanklin JD (1985) Large
losses of total ozone in Antarctica reveal seasonal
ClOx/NOx interaction. Nature 315:207–210
7. Anderson JG, Brune WH, Proffitt MH (1989) Ozone
destruction by chlorine radicals within the Antarctic
vortex: the spatial and temporal evolution of ClO-O 3
anitcorrelation based on in situ ER-2 data. J Geophys
Res 94:11480–11520
8. Molina LT, Molina MJ (1987) Production of Cl 2 O 2 by
the self reaction of the ClO radical. J Phys Chem
91:433–436
9. Solomon S, Garcia RR, Rowland FS, Wuebbles
D (1986) On the depletion of Antarctic ozone. Nature
321:755–758
10. Chipperfield MP (2006) New version of the TOMCAT/SLIMCAT off-line chemical transport model:
intercomparison of stratospheric tracer experiments.
Q J R Meteorol Soc 132:1179–1203. https://doi.org/
10.1256/qj.05.51
11. Rex M, Salawitch RJ, von der Gathen P, Harris NRP,
Chipperfield MP, Naujokat B (2004) Arctic ozone loss
and climate change. Geophys Res Lett 31:L04116.
https://doi.org/10.1029/2003GL018844
12. Chipperfield MP, Fioletov V (Lead Authors)
(2007) Global Ozone. In: Ennis CA (ed) Scientific
assessment of ozone depletion, 2006: pursuant to Article 6 of Montreal Protocol on Substances that Deplete
the Ozone Layer, Chap 3. Global Ozone Research and
Monitoring Project – Report No. 50. World Meteorological Organization, Geneva, p 572
13. Chipperfield MP (1999) Multiannual simulations with
a threedimensional chemical transport model.
J Geophys Res 104:1781–1805
14. Tie XX, Brasseur GP (1995) The response of stratospheric ozone to volcanic eruptions: sensitivity to
atmospheric chlorine loading. Geophys Res Lett
22:3035–3038
15. Fahey DW (Lead Author) (2007) Twenty questions
and answers about the ozone layer: 2006 Update.
Scientific assessment of Ozone Depletion: 2006.
World Meteorological Organization, Geneva, p 50
16. United Nations Environment Program (UNEP)
(1998) Environmental effects of ozone depletion:
Stratospheric Pollution
381