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The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Evolution of Ozone Depleting Substances in the Australian Atmosphere
Presented at:
A Silver Lining: Celebrating 25 Years of
the Montreal Protocol
The Australian Academy of Science
Canberra, 13 September 2012
www.cawcr.gov.au
Paul Fraser FTSE CSIRO Marine and Atmospheric Research, Aspendale
What are ‘Ozone Depleting Substances – ODSs’?
In the context of the Montreal Protocol, an ODS is any chemical containing chlorine (Cl) and/or
bromine (Br), after release into the lower atmosphere, can be transported to the stratosphere,
where it breaks down releasing reactive Cl and/or Br that can significantly destroy stratospheric O3
There are more than 100 ODSs identified for regulation under the Montreal Protocol – an
international agreement designed to protect the stratospheric ozone layer (O3) by controlling ODS
production and consumption
examples:
CFCs (CFC-12: CCl2F2) - refrigerant
HCFCs (HCFC-22: CHClF2) - refrigerant
halons (H-1211: CBrClF2 - fire-fighting agent
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Nature, 1974
Stratospheric sink for chlorofluoromethanes: chlorine atom-catalysed destruction of ozone
M. J. Molina & F. S. Rowland
Department of Chemistry, University of California at Irvine
‘Chlorofluoromethanes are being added to the environment in steadily increasing amounts. These
compounds are chemically inert and may remain in the atmosphere for 40–150 years, and
concentrations can be expected to reach 10 to 30 times present levels. Photodissociation of the
chlorofluoromethanes in the stratosphere produces significant amounts of chlorine atoms, and leads
to the destruction of atmospheric ozone’
CSIRO job interview: ‘What chemicals might be important to measure in the atmosphere?’
Answer: ‘CFCs – they might destroy the Earth’s ozone layer’
1995 Nobel Prize for Chemistry
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Where did it all begin?
1974: wrote to Jim Lovelock
1973 ‘CFCs in and over the North and South Atlantic’, Lovelock et al., Nature
Question: ‘How do I measure CFCs in the atmosphere?’
Answer: ‘GC-ECD – I will visit your laboratory in Australia and teach you’
June 1975: Lovelock & Fraser made the first CFC-11, CH3CCl3 & CCl4 measurements
in the Australian atmosphere The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Professor James Lovelock FRS
1969 - the electron capture detector (ECD)
1974 - Fellow Royal Society
1979 - Gaia: A New Look at Life on Earth
1997 - Blue Planet Prize
1976: Cape Grim, Tasmania - Australia’s first
GHG & ODS Monitoring Station
caravan donated by NASA (previously used in Apollo 13 mission)
1976: commenced CFC-11, CH3CCl3, CCl4 measurements
1978: commenced collection of Cape Grim air archive
1978: joined AGAGE: international network of ODS monitoring and modelling laboratories
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
1978: Cape Grim joins the NASA-funded
AGAGE network
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Ragged Point, Barbados
[13ºN, 59ºW]
Trinidad Head, California
[41º N, 124ºW] Cape Matatula, American Samoa
[14ºS, 171ºW]
Mace Head, Ireland
[53ºN, 10ºW]
Cape Grim, Tasmania
[41ºS, 145ºE]
Cape Grim ODS inventory: currently 35 species
In situ measurement program: 12 times per day, 365 days per year, 27 ODSs
CFCs (6): CFC-11, CFC-12, CFC-113, CFC-114, CFC-115, CFC-13
HCFCs (5): HCFC-22, HCFC-141b, HCFC-142b, HCFC-123, HCFC-124
Halons (3): H-1211, H-1301, H-2402
chloromethanes (4): carbon tetrachloride, methyl chloride, dichloromethane, chloroform
bromomethanes (5): methyl bromide, dibromomethane, bromoform, bromodichloromethane, bromochloromethane
haloethanes, ethenes, propanes (4): methylchloroform, trichlorethylene, perchloroethylene, n-propylbromide
In addition, measured in the Cape Grim Air Archive, 7 ODSs
CFCs (4): CFC-112, CFC-112a, CFC-113a, CFC-114a
HCFCs (2): HCFC-21, HCFC-133a
Halons (1): H-1202
ODSs (16) in red are used internationally to define equivalent stratospheric chlorine
predictions of future O3 levels depend on estimates of future emissions of these 16 ODSs
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Three key elements underpinning Australian
ODS research
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Cape Grim, Tasmania [41°S, 144°E]
Cape Grim air archive: 1978-2011
Law Dome
South Pole
CFC-12 at Cape Grim
refrigerant – atmospheric lifetime 120 years
the major source of stratospheric Cl for decades to come
85% decline in emissions: small remaining use and emissions from ‘banks’
no natural CFC sources The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
methyl chloroform at Cape Grim
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
degreasing solvent (metal surface cleaning) - atmospheric lifetime 5 years
emissions close to zero: 99% decline, almost completely removed from the atmosphere
a major cause of the decline in total Cl since the mid-1990s
Methyl bromide at Cape Grim
natural background level: 5-6 ppt maintained by emissions from the oceans
agricultural, structural and quarantine fumigant
agricultural and structural emissions controlled by Montreal Protocol – rapid decline
most ‘above background’ CH3Br now due to quarantine uses
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
HCFC-141b at Cape Grim
used in commercial refrigerant blends: 2 phase emissions
baseline data and local pollution episodes shown
baseline data → global emissions
pollution data → local (SE Australian/Australian) emissions The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
‘Stratospheric chlorine’: past and future
20% from natural sources: CH3Cl, CH3Br
80% industry/agriculture: CFCs, halons,
CH3Br etc.
fallen 8% since peak in mid-1990s
future dominated by CFCs already present in
the atmosphere
return to 1980 levels by 2050
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Column O3 at Halley, Antarctica, & Melbourne, Australia
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
strong correlation between stratospheric ‘chlorine’ and total ozone
ozone recovery has commenced above Antarctica and at mid-latitudes
Global & Australian ODS emissions from atmospheric data
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
global peak: 9000 M tonnes CO2-e; Australian peak ~40 M tonnes (0.5% of global)
Australian ODS emissions decline since 1990: 30 M tonnes CO2-e (5% of total Australian GHG emissions)
equivalent to taking 300,000 cars off the road
Australian CO2-e changes (1990-2010) → CO2: 125 Mt; CH4: -5 Mt; N2O: 5 Mt; HFCs/PFCs/SF6: 2 Mt
Montreal Protocol: most successful climate change mitigation policy option adopted thus far
Australian ODS research: ……achievements
first continuous measurements of ODSs in the Southern Hemisphere
Cape Grim: the most important facility for measurement ODSs in the SH
Cape Grim Air Archive, described by Megan Clark (CSIRO CEO) as a ‘national treasure’
discovered 14 previously unidentified ODSs in atmosphere at Cape Grim:
CFCs: CFC-13, CFC-112, CFC-112a, CFC-113a, CFC-114, CFC-114a, CFC-115
HCFCs: HCFC-21, HCFC-123 , HCFC-133a, HCFC-141b, HCFC-142b
halons: H-1202 , H-2402
observation-based atmospheric history of all the important ODSs from 1930s to present
observation-based estimate of effective stratospheric chlorine: 1930s-present
Australian ODS data: all 7 international assessment of ozone depletion since the late-1980s
‘top-down’ estimate of Australian ODS emissions
demonstrate the significant Montreal Protocol impact on reducing Australian GHG emissions
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
Dedication: F. Sherwood ‘Sherry’ Rowland:
1927 - 2012
The Centre for Australian Weather and Climate Research
A partnership between CSIRO and the Bureau of Meteorology
‘He inspired many to walk in the shadow of his greatness’
- fellow Nobel Laureate, Prof. Mario Molina, MIT, March 2012
1952: PhD, U. Chicago (W. Libby –
Nobel Prize for Chemistry 1960)
1974: the Nature paper
1989: Japan Prize
1993: President AAAS
1993: Peter Debye Award (ACS)
1994: Roger Revelle Medal (AGU)
1995: Nobel Prize for Chemistry with M.
Molina and P. Crutzen
The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Thank you www.cawcr.gov.au
CSIRO/Bureau of Meteorology ODS Team
Paul Fraser, Nada Derek, Bronwyn Dunse, David Etheridge, Paul Krummel,
Ray Langenfelds, Paul Steele, Cathy Trudinger & the late Laurie Porter
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