Atmospheric aerosol, air quality and climate: from the local to the global scale

1. Atmospheric aerosol, air quality and climate: from the local to the global scale Sandro Fuzzi Institute of Atmospheric Sciences and Climate National Research Council Bologna Atmospheric Chemistry

2. The atmosphere: a multiphase system • The atmosphere is a multiphase system, insofar as all three phases are simultaneously present: gas, solid, liquid • Dry aerosol constitutes the solid phase • Wet aerosol and cloud/fog droplets constitute the liquid phase Atmospheric Chemistry

3. Aerosol: definition “a stable suspension of solid and/or liquid in air” Size interval 0.003 - 100 mm Atmospheric Chemistry

4. Aerosol mass distribution Atmospheric Chemistry

5. Aerosol mass and number concentrations Atmospheric Chemistry

6. atmosphere transport - transformation deposition emission surface Cycle of atmospheric aerosol Atmospheric Chemistry

7. Emission of aerosol in the atmosphere • Fragmentation processes • (primary aerosol, mostly super-micron size) • Combustion processes • (primary aerosol, wide size range) • Conversion processes • (secondary aerosol, sub-micron size) Atmospheric Chemistry

8. Global aerosol sources (Tg/yr) Natural3060 Primary Soil mobilization 1500 Sea salt 1300 Volcanic aerosol 30 Biological particles 50 Secondary Sulphate (conv. SO2) 100 Nitrate (conv. NOX) 20 Organic aerosol (conv. BVOC) 60 Anthropogenic395 Primary Industrial aerosol 100 Fossil fuel combustion 25 Biomass burning 80 Secondary Sulphate (conv. SO2) 140 Nitrate (conv. NOX) 40 Organic aerosol (conv. AVOC) 10 Atmospheric Chemistry

9. Aerosol optical thicknessModerate Resolution Imaging Spectroradiometer (MODIS) on NASA Terra satellite AOT monthly average year 2001 AOT < 0.1 remote atmosphere AOT > 0.2 polluted atmosphere Jan. May Feb. July Feb. Mar Aug. Sept. Apr Apr Atmospheric Chemistry

10. Aerosol optical thickness(June-August 2001) Atmospheric Chemistry

11. Saharan dust plume (2 March 2002)SeaWIFFSsatellite pollution aerosol dust Atmospheric Chemistry

12. Gas-to-particle-conversion • Two or more gaseous species react producing a low vapor pressure compound • The new compound can: • condense onto a pre-existing particle • nucleate forming a new ultra-fine particle Atmospheric Chemistry

13. Nucleation • Evidence of formation of “new” particles of a few nm size reported by Aitken already in 1897 • Measurements possible only in the last few years (DMPS) • Mechanisms proposed: • binary nucleation (H2O-H2SO4) • ternary nucleation (H2O-H2SO4-NH3) • ion induced nucleation Atmospheric Chemistry

14. Formation and growth of ultra-fine particles (Po Valley) Laaksonen et al., Geophys. Res. Lett., 2005 18:00 24:00 00:00 10:30 13:30 Atmospheric Chemistry

15. Frequency of nucleation in the Po Valley Atmospheric Chemistry

16. Gas/particle connection Meng et al., Science, 1997 Atmospheric Chemistry

17. Aerosol removal Two series of mechanisms are responsible for aerosol removal: • dry removal (sedimentation, turbulence, impact) • wet removal (incorporation in clouds and deposition through precipitation) Atmospheric Chemistry

18. 100 1000 10 100 1 accumulation mode hours 10 days 0.1 1 Brownian diffusion coagulation 0.01 sedimentation 0.001 0.1 0.001 0.01 0.1 1 10 100 diameter (micrometers) Aerosol residence time Atmospheric Chemistry

19. Aerosol chemical composition • Unlike atmospheric gases, aerosols cannot be characterised by a single parameter such as concentration. Instead atmospheric aerosols are characterised by their physical, chemical and optical properties, as well as their state of mixture (internal or external) and phase (solid, liquid or ice). Atmospheric Chemistry

20. Aerosol complexity • Various chemical species (elemental, organic and inorganic) are present • Solid, liquid and ice particles from a few nanometers to a few hundred micrometers are present • Internally/externally mixed system exists • Temporal (diurnal, seasonal and annual), and spatial (long/lat and altitude) variability and systematic relationships need to be considered Atmospheric Chemistry

21. Aerosol state of mixing Atmospheric Chemistry

22. Carbonaceous aerosol • Until recently, only the inorganic fraction of the aerosol was known • Now we know that carbonaceous aerosols are ubiquitous and can contribute from 20% to > 80% of the mass of fine aerosol Atmospheric Chemistry

23. Forms of carbon in the aerosol • black carbon (BC) • organic carbon (OC) total carbon (TC) = BC + OC Atmospheric Chemistry

24. OC • BC • inorganic Composition of fine aerosol remote marine area 1 mg/m3 polluted marine area 6 mg/m3 remote forested area 3 mg/m3 biomass burning 60 mg/m3 polluted continental area 40 mg/m3 Atmospheric Chemistry

25. Sources of fine organic aerosol • Primary • biomass burning • fossil fuel • biological material (?) • Secondary • anthropogenic VOC oxidation • biogenic VOC oxidation Atmospheric Chemistry

26. Global emissions of fine organic aerosol (Tg/y) Atmospheric Chemistry

27. Size-segregated aerosol chemical composition Continental polluted (Po Valley) Polluted site in Asia (Korea) Saharan dust (Mt. Cimone) Finnish boreal forest Biomass burning in Amazzonia Marine remote site (Mace Head) Atmospheric Chemistry

28. European aerosol climatology Atmospheric Chemistry

29. Compliance with air quality standards Atmospheric Chemistry

30. PM10 vs. PM2.5 Atmospheric Chemistry

31. Seasonality of PM2.5 and Na Atmospheric Chemistry

32. Aerosol chemical composition Atmospheric Chemistry

33. Aerosol size-segregated chemistry Gent, Belgium Marseille, France Atmospheric Chemistry

34. Aerosol environmental effects • human health • vegetation and materials • visibility • climate • hydrological cycle Atmospheric Chemistry

35. Effects on human health • Mechanisms by which ihalable atmospheric particles affect human health are still poorly known. Two types of interactions can however be identified: • mechanical: inflammation oftissues or receptors chemical: inflammation oftissues or receptors, damages of cellular tissues, mutagenesis of cells COST action 633: Particulate matter: Properties related to health effects http://cost.cordis.lu/src/action_detail.cfm?action=633 Atmospheric Chemistry

36. Effects on vegetationand materials • Are mainly due to chemical reactions of particulate matter deposited on the surfaces activated by water (dew, fog, precipitation) • The reaction products in solution can then produce damages to materials and vegetation tissues Atmospheric Chemistry

37. Damage to leaves Atmospheric Chemistry

38. Damage to materialsPortal figure of Herten Castle, Germany (1702) 1968 1908 Atmospheric Chemistry

39. range of actual concentrations of aerosol in the atmosphere Effect on visibility Atmospheric Chemistry

40. Visibility on a clear and a hazy day Denver, Colorado Atmospheric Chemistry

41. Ji Parana, Brasil Atmospheric Chemistry

42. Aerosol-climate • The atmospheric aerosol influences the Earth’s climate in two ways: • direct effect: reflecting the incoming solar radiation back to space; • indirect effect: acts as CCN favoring formation of clouds which can also reflect solar radiation back to space . • Both these mechanisms exert a cooling effect on climate aerosol sources Atmospheric Chemistry

43. Climate forcings Atmospheric Chemistry

44. Suppression of precipitation low concentration of aerosol high concentration of aerosol threshold for production of precipitation Ramanathan et al., Science, 2001 Visible and InfraRed Sensor (VIRS) Satellite NASA-Tropical Rainfall Measuring Mission (TRMM) Atmospheric Chemistry

45. Microstructure of clouds NOAA –AVHRR satellite red = larger droplets yellow = smaller droplets Port Augusta power plant Port Pirie lead smelter Adelaide port oil refineries South Australia Rosenfeld, Science, 2000 Atmospheric Chemistry

46. Review on aerosols in Europe A European Aerosol Phenomenology. 1: physical characteristics of particulate matter at kerbside, urban, rural and background sites in Europe Van Dingenen, R., F. Raes, J.-P. Putaud, U. Baltensperger, E. Brüggemann, A. Charron, M.C. Facchini, S. Decesari, S. Fuzzi, R. Gehrig, H.-C. Hansson, R.M. Harrison, C. Hüglin, A.M. Jones, P. Laj, G. Lorbeer, W. Maenhaut, F. Palmgren, X. Querol, S. Rodriguez, J. Schneider, H.ten Brink, P. Tunved, K. Tørseth, B. Wehner, E. Weingartner, A. Wiedensohler and P. Wåhlin Atmos. Environ., 38, 2561-2577 (2004) A European Aerosol Phenomenology. 2: chemical characteristics of particulate matter at kerbside, urban, rural and background sites in Europe Putaud, J.-P., F. Raes, R. Van Dingenen J.-P. U. Baltensperger, E. Brüggemann, M.C. Facchini, S. Decesari, S. Fuzzi, R. Gehrig, H.-C. Hansson, C. Hüglin, P. Laj, G. Lorbeer, W. Maenhaut, N. Mihalopoulos, K. Müller, X. Querol, S. Rodriguez, J. Schneider, G. Spindler, H.ten Brink, K. Tørseth, B. Wehner and A. Wiedensohler Atmos. Environ., 38, 2579-2595 (2004) Atmospheric Chemistry

47. Reviews on organic aerosol Organic aerosol and global climate modelling: A review Kanakidou, M., J. H. Seinfeld, S. N. Pandis, I. Barnes, F. J. Dentener, M. C. Facchini, R. van Dingenen, B. Ervens, A. Nenes, C. J. Nielsen, E. Swietlicki, J.P. Putaud, Y. Balkanski, S. Fuzzi, J. Hjorth, G. K. Moortgat, R. Winterhalter, C. E. L. Myhre, K. Tsigaridis, E. Vignati, E. G. Stephanou, J. Wilson Atmos. Chem. Phys., 5, 1053-1123 (2005) A critical assessment of the current state of knowledge and research needs on the role of organic aerosols in the atmosphere, climate, and global change Fuzzi, S., M.O. Andreae, B. Huebert, M. Kulmala, T. Bond, M. Boy, S.J. Doherty, A. Guenther, M. Kanakidou, K. Kawamura, V.-M. Kerminen, U. Lohmann, U. Pöschl, L.M. Russell Atmos. Chem. Phys., 6, 2017-2038 (2006) Atmospheric Chemistry

48. The End ...thank you for your attention!!! Atmospheric Chemistry