Evolution of Ozone Depleting Substances in the Australian Atmosphere - PowerPoint PPT Presentation

Evolution of Ozone Depleting Substances in the Australian Atmosphere Paul Fraser FTSE CSIRO Marine and Atmospheric Research, Aspendale www.cawcr.gov.au Presented at: A Silver Lining: Celebrating 25 Years of the Montreal Protocol The Australian Academy of Science Canberra, 13 September 2012 The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

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 O 3  There are more than 100 ODSs identified for regulation under the Montreal Protocol – an international agreement designed to protect the stratospheric ozone layer (O 3 ) by controlling ODS production and consumption  examples:  CFCs (CFC-12: CCl 2 F 2 ) - refrigerant  HCFCs (HCFC-22: CHClF 2 ) - refrigerant  halons (H-1211: CBrClF 2 - fire-fighting agent The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

Where did it all begin? 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

1974: wrote to Jim Lovelock  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  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, CH 3 CCl 3 & CCl 4 measurements in the Australian atmosphere The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

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, CH 3 CCl 3 , CCl 4 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 Trinidad Head, California Ragged Point, Barbados Cape Matatula, American Samoa [41º N, 124ºW] [13ºN, 59ºW] [14ºS, 171ºW] Cape Grim, Tasmania Mace Head, Ireland [41ºS, 145ºE] [53ºN, 10ºW] The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

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 O 3 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 Cape Grim, Tasmania [41°S, 144°E] South Pole Cape Grim air archive: 1978-2011 Law Dome The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

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  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 The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

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’ CH 3 Br 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: CH 3 Cl, CH 3 Br  future dominated by CFCs already present in the atmosphere  80% industry/agriculture: CFCs, halons, CH 3 Br etc.  return to 1980 levels by 2050  fallen 8% since peak in mid-1990s The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

Column O 3 at Halley, Antarctica, & Melbourne, Australia  strong correlation between stratospheric ‘chlorine’ and total ozone  ozone recovery has commenced above Antarctica and at mid-latitudes The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

Global & Australian ODS emissions from atmospheric data  global peak: 9000 M tonnes CO 2 -e; Australian peak ~40 M tonnes (0.5% of global)  Australian ODS emissions decline since 1990: 30 M tonnes CO 2 -e (5% of total Australian GHG emissions)  equivalent to taking 300,000 cars off the road  Australian CO 2 -e changes (1990- 2010) → CO 2 : 125 Mt; CH 4 : -5 Mt; N 2 O: 5 Mt; HFCs/PFCs/SF 6 : 2 Mt  Montreal Protocol: most successful climate change mitigation policy option adopted thus far The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology

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 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 ‘He inspired many to walk in the shadow of his greatness’ - fellow Nobel Laureate, Prof. Mario Molina, MIT, March 2012 The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology