Photochemical ozone creation potentials
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Goal, Scope and Background
Photochemical ozone creation potentials (POCPs) typically used in life cycle impact assessment (LCIA) to address the impact category ‘photo-oxidant formation’ only provide factors for particular volatile organic compounds and do not take into account background concentrations and meteorological conditions. However, the formation of ozone from volatile organic compounds (VOCs), carbon monoxide (CO) and nitrogen oxides (NOx) is highly dependent on the background pollutant concentrations and meteorological conditions. Some LCIA manuals therefore recommend working with potentials for high background concentrations of NOx (Derwent 1998), and potentials for low background concentrations of NOx (Andersson-Sköld 1992).
This study has introduced an improved set of POCPs independently of meteorological and emission conditions specific to a given period or location. Whereas current POCP values may be relevant to estimate the photo-oxidant formation over a certain (temporally and spatially well-defined) domain, this study has further introduced more relevant values with respect to potential impacts of ozone on human health and environment.
For the computation of POCP values on the scale of Western Europe, independently of meteorological and emission conditions specific to a given period or location, a Eulerian chemistry-transport numerical model (CHIMERE-continental) has been implemented over three summer seasons. POCPs have been evaluated for ten VOC species (including the whole VOC group), CO and NOx. The coherence of this new set of POCP values with previous studies has been checked. The spatial representa-tivity of POCP values over the simulation domain in Europe has also been addressed. The robustness of these POCP values to changes in the implemented chemical mechanism used in our model has been checked.
Results and Discussion
The POCPs computed in this study were generally lower than the POCPs calculated in previous studies. In the previous studies, but not here, the POCPs have been calculated with particular meteorological conditions (during anti-cyclonic, fair weather conditions) or emission levels (high polluted backgrounds) known to be optimal with respect to ozone formation. Despite the quantitative variations in the POCP values, we have found a good agreement in the relative ranking of the pollutant species between this study and previous studies. It was also shown that POCP values display significant spatial variability over Western Europe (the largest spatial differences were obtained for NOx where the sign of the POCP value even changes from region to region).
Finally, the temporally and spatially averaged values obtained here for the POCP index update previous values and represent an attempt to generate the most appropriate and accurate scale for European conditions independently of meteorological and emission conditions specific to a given period or location.
Recommendations and Outlook
These new PCOPs should be useful to LCIA-practitioners in further life cycle impact assessment. However, for the NOx species, we do not recommend the use of the POCP value for LCIA.
KeywordsCharacterization factors life cycle impact assessment (LCIA) photochemical atmospheric model photochemical ozone creation potentials (POCP) photo-oxidant formation
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- Andersson-Sköld Y, Grennfelt P, Pleijel K (1992): Photochemical ozone creation potentials: a study of different concepts.J. Air Waste Management Association, 42 (9) 1152–1158Google Scholar
- Carter WPL (1994): Development of ozone reactivity scales for volatile organic compounds. Journal of the Air and Waste Management Association 44, 881–899Google Scholar
- DeMore WB, Sander SP, Golden DM, Hampson RF, Kurylo MJ, Howard CJ, Ravishankara AR, Kolb CE, Molina MJ (1997): Chemical kinetics and photochemical data for use in stratospheric modeling. Evaluation 12, JPL publication 97, 4, JPL, Pasadena, USGoogle Scholar
- Derognat C (1998): Elaboration d’un code chimique simplifié applicable à l’etude de la pollution photooxydante en milieu urbain et rural. Rapport de stage de DEA (diploma thesis report), Universite Pierre et Marie Curie, Paris 6, FranceGoogle Scholar
- Derognat C (2002): Pollution photooxydante à l’échelle urbaine et interaction avec l’echelle régionale. Thèse de doctorat, Université Paris 6Google Scholar
- Derwent RG, Jenkin ME (1991): Hydrocarbons and the long-range transport of ozone and PAN across Europe. Atmospheric Environment, 25A, 1661–1678Google Scholar
- EMEP Status Report 1/03 Part III (2003) Transboundary acidification and eutrophication and ground level ozone in Europe: Source-Receptor relationships, EMEP/MSC-W Report, available on www.emep.int/common puhlications.htmlGoogle Scholar
- GENEMIS (Generation of European Emission Data for Episodes) project (1994: EUROTRAC Annual report 1993, Part 5, EUROTRAC International Scientific Secretariat, Garmisch-PartenkirchenGoogle Scholar
- Goedkoop M, Spriensma R (1999): The Eco-Indicator 99. A damage oriented method for Life Cycle Impact Assessment, Methodology Annex www.pre.nl. 108 pp.Google Scholar
- Heijungs R, Guinée JB, Huppes G, Lamkreijer RM, Udo de Haes HA, Wegener Sleeswijk A, Ansems AMM, Eggels PG, van Duin R, de Goede HP (1992): Environmental Life Cycle Assessment of Products. Guide (Part 1) and Backgrounds (Part 2) October 1992, prepared by CML, TNO and B&G. Leiden. English Version 1993Google Scholar
- Hofstetter P (1998): Perspectives in Life Cycle Impact Assessment; A Structured Approach to Combine Models of the Technosphere, Ecosphere and Valuesphere. Kluwer Academic Publishers, Dordrecht, The NetherlandsGoogle Scholar
- International Organization for Standardization (ISO) (1999): Environmental Management — Life cycle Assessment — Life cycle Impact Assessment. ISO Standard 14042. Prepared by Technical committee 207, sub committee 5 (ISO/TC 205/ SC5)Google Scholar
- Lattuati M (1997): Impact des émissions européennes sur le bilan de l’ozone troposphérique à l’interface de l’Europe et de l’Atlantique Nord: apport de la modélisation lagrangienne et des mesures en altitude. Thèse de doctorat, Université Paris 6Google Scholar
- McCabe LC (Chairman) (1952): Air Pollution. Proceedings of the United States Technical Conference on Air Pollution. McGraw-Hill Book Comp, New YorkGoogle Scholar
- Middleton P, Stockwell WR, Carter WP (1990): Aggregation and analysis of volatile organic compound emissions for regional modeling. Atmospheric Environment, 24, 1107–1133Google Scholar
- RE.CO.R.D. — BIO Intelligence Service, Etude n 99-1004/lA (2000): Analyse critique des indicateurs de catégories d’impact sur l’environnement dans les analyses de cycle de vieGoogle Scholar
- Seinfeld JH (1995): Chemistry of ozone in the urban and regional atmosphere. Progress and Problems in Atmospheric Chemistry, Advanced Series in Physical Chemistry Vol. 3, Chapter 2Google Scholar
- Seinfeld JH, Pandis SN (1998): Atmospheric chemistry and physics. Wiley-Interscience, New YorkGoogle Scholar
- Simpson D (1992): Long period modelling of photochemical oxidants in Europe. Calculations for July 1985. Atmospheric Environment 26, 1609–1634Google Scholar
- Society of Environmental Toxicology and Chemistry (SETAC) (1993a): Conceptual Framework for Life Cycle Impact Assessment. Fava JA, Consoli F, Denison RA, Dickson K, Mohin T, Vigon BW (eds). SETAC, Pensacola, FL, USAGoogle Scholar
- Toxicology and Chemistry (SETAC) (1993b): Guidelines for Life Cycle Assessment: A Code of Practice. Consoli F, Allen D, Boustead I, Fava J, Franklin W, Jensen A, de Oude N, Parrish R, Perriman R, Postlethwaite D, Quay B, Séguin J, Vigon BW (eds). SETAC, Pensacola, FL, USAGoogle Scholar
- Society of Environmental Toxicology and Chemistry (SETAC) (1997): Life Cycle Assessment: The State-of-the-Art. Barnthouse L, Fava J, Humphreys K, Hunt R, Laibson L, Noesen S, Owens J, Todd J, Vigon B, Weitz K, Young J (eds). SETAC, Pensacola, FL, USAGoogle Scholar
- UNECE (1990): Draft technical annex on classification of volatile organic compounds based on their photochemical ozone creation potential (POCP). United Nations Economic Commission for Europe (Economic and Social Council), GenevaGoogle Scholar
- Verwer JG, Simpson D (1991): Explicit methods for stiff ODEs from atmospheric chemistry, Report NM-R9409, ISSN 0169-0388, CWI, P.O. Box 94079, 1090 GB Amsterdam, The NetherlandsGoogle Scholar