1. Modification of the chemical environment during long-range transport M. Auvray & I. Bey GEOS-CHEM Meeting – April 2005 Swiss Federal Institute of Technology, Lausanne, Switzerland Laboratoire de Modélisation de la Chimie Atmosphérique http://lmca.epfl.ch Acknowledgements: C. Reeves (chemical terms), S. Turquety (biomass burning emissions), ACSOE – EXPORT – ICARTT/ITOP teams, …

2. Scientific questions 1. How is the model capable to reproduce observed O3 production and loss rates (focus on the North Atlantic/Europe area) ? 2. To what extent long-range transport modify these chemical terms? Perturbation of O 3 chemical terms by long range transport

3. GEOS-CHEM version v7-01-02 Resolution 2° x 2.5° EMEP emissions over Europe One-year initialisation Hemispherical Background Ozone produced from natural emissions of NO x and VOCs + CH 4 + stratospheric ozone North American contribution Ozone produced from anthropogenic emissions emitted over North America European contribution Ozone produced from anthropogenic emissions emitted over Europe Asian contribution Ozone produced from anthropogenic emissions emitted over Asia Methodology The Model Definitions Aircraft campaigns

4. European contribution Asian contribution N. American contribution Hemispheric background O 3 budget over the ACSOE domain, April 1997 Comparison with key observed chemical species - ACSOE Observations Model N. Am. Europe April September O 3 (ppbv) CO (ppbv) NO (pptv) PAN (pptv) NOy (pptv)

5. Evaluation of O 3 production and loss term with ACSOE, April 1997 - 1 GEOS-CHEM Reeves et al. Data from Reeves et al., JGR, 2002 Grid-box model constrained by measured in situ photolysis rate and observed concentrations of O 3, H 2 O, CO, H 2 O 2 and CH 3 OOH

6. NO + HO 2  NO 2 + OHNO + CH 3 O 2  NO 2 + CH 3 OO 3 + OH  O 2 + HO 2 O 3 + HO 2  2 O 2 + OH OH O 3 + hν  2 OH GEOS-CHEM Reeves et al. Evaluation of individual reactions Evaluation of O 3 production and loss term with ACSOE, April 1997 - 2 Data from Reeves et al., JGR, 2002

7. Sensitivity of O 3 chemical terms to ship emissions during ACSOE, April 1997 Simulation without ship emissions Standard simulation Data from Reeves et al., JGR, 2002

8. Comparison with key observed chemical species - EXPORT, July & August 2000 O 3 budget over the EXPORT domain European contribution Asian contribution N. American contribution Hemispheric background O 3 (ppbv) CO (ppbv) NO (pptv) NO 2 (pptv) PAN (pptv) NOy (pptv) Observations Model – EMEP N. Am. Europe Model – no EMEP

9. GEOS-CHEM Reeves et al. Evaluation of O 3 production and loss term with EXPORT, July & August 2000 Data from Reeves et al., EXPORT-E2 Final Report, 2002 Zoom

10. 2. Perturbation of the background environment over the North Atlantic ocean by North American plume North American plume: boxes where CO NAm > (median + st dev) CO NAm Background: boxes whereCO < median CO O 3 Prod Loss [ppbv/day]O 3 net Prod [ppbv/day] NAm Plume Difference Background

11. 3. Seasonal variations of production and loss of O 3 over the North Atlantic ocean JanuaryAprilJulyOctober O 3 net Prod [ppbv/day] O 3 Prod Loss [ppbv/day] NAm Plume Difference Background

12. Preliminary conclusion ACSOE: O 3 production is overestimated, specially < 4 km O 3 loss is underestimated, specially < 3 km Next step: Examine sensitivity of O 3 production and loss rates 1. To different parameters: - relative humidity - J-value - heterogeneous reactions on aerosols 2. Using outputs from another 3D global model (MOZECH – collaboration with M. Schultz, MPI-Hamburg) 3. Use the ICARTT/ITOP data EXPORT: O 3 net production is overestimated in upper troposphere

13. DC8 P3 BAE 146 Falcon O 3 (ppbv) CO (ppbv) NO (pptv) NO 2 (pptv) PAN (pptv) NOy (pptv) Observations Model – S. Turquety Biomass burning emissions Comparison ITOP/ICARTT obs. - GEOS-CHEM

14. Continuation of the ICARTT/ITOP project Focus on long-range transport of aerosol: how does it impact Europe? Case-study: aerosol layer, seen by the DLR and by the lidar at Paris (Courtesy: Hans Schlager) DLR Falcon 23 July 04

15. Additional slides

16. Emissions in GEOS-CHEM – NOx in July Basic inventoryEMEP inventory 1998-2000

17. Emissions in GEOS-CHEM – CO in July Basic inventoryEMEP inventory 1998-2000

18. HNO 3 RH O2O2 H2OH2O O2O2 RCHO NO NO 2 HO 2 OH RO 2 RO NO 2 NO hνhν O3O3 O2O2 O hνhν O3O3 O2O2 O NO + HO 2  NO 2 + OHNO + CH 3 O 2  NO 2 + CH 3 O PO 3 = k 1 [NO] [HO 2 ] + k 2 [NO] [CH 3 O 2 ] k1k1 k2k2 Production of O 3

19. HO 2 OH O3O3 O2O2 hνhν O 1D H2OH2O O3O3 O2O2 O 3 + OH  O 2 + HO 2 O 3 + HO 2  2 O 2 + OH OH O 3 + hν  2 OH LO 3 = k 3 [O 3 ] [OH] + k 4 [O 3 ] [HO 2 ] + J [O 3 ] k3k3 k4k4 J Destruction of O 3

20. HNO 3 RH O2O2 H2OH2O O2O2 RCHO NO NO 2 HO 2 OH RO 2 RO NO 2 NO hνhν O3O3 O2O2 O hνhν O3O3 O2O2 O NO + HO 2  NO 2 + OHNO + CH 3 O 2  NO 2 + CH 3 O O3O3 O2O2 hνhν O 1D H2OH2O O3O3 O2O2 O 3 + OH  O 2 + HO 2 O 3 + HO 2  2 O 2 + OH OH O 3 + hν  2 OH Production and destruction of O 3

21. HNO 3 RH O2O2 H2OH2O O2O2 RCHO HO 2 OH RO 2 RO NO 2 NO hνhν O3O3 O2O2 O hνhν O3O3 O2O2 O NO + HO 2  NO 2 + OHNO + CH 3 O 2  NO 2 + CH 3 O O3O3 O2O2 hνhν O 1D H2OH2O O3O3 O2O2 O 3 + OH  O 2 + HO 2 O 3 + HO 2  2 O 2 + OH OH O 3 + hν  2 OH CO NO y NO 2 NO PAN + NO 2

22. Evaluation of O 3 : a case study – ACSOE, 14 th of September 1997 Auvray and Bey, 2005

23. DC8 P3 BAE 146 Falcon Location of the ICARTT/ITOP campaigns