1 / 54

Special issue AMMA SOP0 LISA contribution

Special issue AMMA SOP0 LISA contribution. P. Formenti.

holst
Download Presentation

Special issue AMMA SOP0 LISA contribution

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Special issue AMMA SOP0 LISA contribution P. Formenti 1) Rajot et al., General overview of Banizoumbou results2) Formenti et al., Physico-chemical characteristics of aerosols over Western Africa (I): results from the AMMA dry season campaign3) Alfaro et al., Spectral optical properties of mineral dust and biomass burning and their mixing Second SOP0 workshop, Exeter 15 May 2007

  2. Scientific questions within SOP0 1) What are the physico-chemical and optical properties of mineral dust in the Sahel ? (source regions) 2) How to predict dust optical properties knowing their physico-chemical properties ? 3) How to account for mixing with other aerosol species ? 4) How do mineral dust aerosols modify the solar and terrestrial radiation budgets at the local and the regional scales ? Second SOP0 workshop, Exeter 15 May 2007

  3. SOP0 operation Timing DABEX DODO ULM 12/02 16/02 11/01 21/01 27/01 14/01 13/01 24/01 01/02 03/02 DJOUGOU BANIZOUMBOU M’BOUR Second SOP0 workshop, Exeter 15 May 2007

  4. Long term (2005-2008) + intensive observations (Jan-Fev et Jun-Jul 2006) Banizoumbou Second SOP0 workshop, Exeter 15 May 2007

  5. Laboratory "Belgique" Sampling inlets Banizoumbou ground-based station Second SOP0 workshop, Exeter 15 May 2007

  6. Ground-based measurements at Banizoumbou (1 / 2) On-line measurements (sampling interval) • Number and mass concentration, GRIMM OPC and TEOM (5-min) • Number size distribution, GRIMM OPC (5-min) • Spectral absorption coefficient, Magee Aethalometer (5-min) • Spectral scattering coefficient, TSI nephelometer (5-min) • Global, diffuse & direct radiation, MFRSR-7 shadowband radiometer (1-min) • Global and spectral downwelling radiation, ARM ancillary • Aerosol vertical profile, lidars (B. Heese and F. Cairo) • Ozone concentration (5-min) • Meteorology Second SOP0 workshop, Exeter 15 May 2007

  7. Filter sampling and analysis Aerosol sampling (sampling interval/frequency) Bulk • Elemental Chemical composition (12-h + events, total + PM10) • Water soluble fraction (12-h + events) • Carbon content (24-h) • Mineralogy (12-h + events) • Single-particle composition and morphology (12-h + events) Size-segregated • Chemical composition on 4- and 13-stage impactors (24-h) s Second SOP0 workshop, Exeter 15 May 2007

  8. GRIMM GRIMM NEPHELOMETRE TSI AETHALOMETRE Magee TEOM Sampling strategy: schematics Sampling inlets (physico-chemical and optical measurements) ARM ancillary Lidars Shadow-band Second SOP0 workshop, Exeter 15 May 2007

  9. Ground-based, Banizoumbou Air in To the instruments To the buried instrumented container Second SOP0 workshop, Exeter 15 May 2007

  10. Filter collection onboard the UK BAe146 Air in Air in 90-mm SFU1: Inorganics 47-mm SFU2: Organic and Elemental carbon 0.4-µm Nuclepore Quartz Air out Air out • Elemental Chemical composition (all) • Water soluble fraction (depends on concentration) • Mineralogy (depends on concentration) • Single-particle composition and morphology (selected events) Second SOP0 workshop, Exeter 15 May 2007

  11. Collected samples • About 500 bulk samples collected at the ground-based station • Dust and aged BB • About 120 samples collected on the aircraft • SLR from ~ 170 feet to FL120 • Various aerosol types (dust, fresh BB, aged BB, background, their mixing) Second SOP0 workshop, Exeter 15 May 2007

  12. Status of analysis Second SOP0 workshop, Exeter 15 May 2007

  13. Dust aerosols are found at to the surface BB Second SOP0 workshop, Exeter 15 May 2007

  14. Episodes of dust and biomass burning Banizoumbou, Jan 2006 BB Dust Second SOP0 workshop, Exeter 15 May 2007

  15. Mineral dust from different source regions Second SOP0 workshop, Exeter 15 May 2007

  16. Bulk composition of dust from ground-based and aircraft samples (DABEX) : Si vs Al Si vs Al Second SOP0 workshop, Exeter 15 May 2007

  17. Bulk composition of dust from ground-based and aircraft samples (DABEX) : Fe vs Al Ongoing analysis to quantify the proportion of iron oxydes Second SOP0 workshop, Exeter 15 May 2007

  18. Individual particle analysis of dust samples (B160, B161, B165) Iron oxyde • Iron oxydes observed in the fine fraction (4-5% by number), results of the mass analysis are still missing • "Uncontaminated" dust, soot particles less than 1% by number, although trajectories show that airmasses where dust plumes were sampled might have come in contact with pollution Second SOP0 workshop, Exeter 15 May 2007

  19. Dust from Mauritania is enriched in minerals such as halite (Na-rich) Confirmed by microscopy analysis Second SOP0 workshop, Exeter 15 May 2007

  20. Measuring the attenuation of the Al signal gives indication on particle size B238N3 20% attenuation corresponds to aerodynamic VMD of ~ 2 µm (geometric 1.2 µm) Second SOP0 workshop, Exeter 15 May 2007

  21. The Ca-to-Fe elemental ratio as a marker of major source region Niger (DABEX) (DODO) Local erosion Second SOP0 workshop, Exeter 15 May 2007

  22. Mineralogy from ground-based samples BB Ca- rich Quartz Clays Second SOP0 workshop, Exeter 15 May 2007

  23. Mineral dust ubiquitous even in elevated BB layer Second SOP0 workshop, Exeter 15 May 2007

  24. BB episode in Banizoumbou Tracers of biomass burning K vs Al Second SOP0 workshop, Exeter 15 May 2007

  25. Individual particle analysis of biomass burning samples B158N4 • Coarse fraction dominated by mineral dust • Fine and coarse fraction are externally mixed Second SOP0 workshop, Exeter 15 May 2007

  26. Conclusions • Analysis still ongoing • won't be ready to submit in July • delaying some of your work (water-soluble fraction) • Analysis is focusing on mineral dust • Biomass burning Second SOP0 workshop, Exeter 15 May 2007

  27. Second SOP0 workshop, Exeter 15 May 2007

  28. Second SOP0 workshop, Exeter 15 May 2007

  29. Second SOP0 workshop, Exeter 15 May 2007

  30. Second SOP0 workshop, Exeter 15 May 2007

  31. Tracers of biomass burning SAFARI2000, aged smoke K+/BC = 0.54 Second SOP0 workshop, Exeter 15 May 2007

  32. Aerosol optical properties in Niger during the dry season Alfaro et al. Objectives: Document and explain the temporal variability of the spectral dependence of scattering and absorption measured at ground level in Banizoumbou. Second SOP0 workshop, Exeter 15 May 2007

  33. DATA AVAILABLE from 13 Jan. to 12 Feb.Optical propertiesat ground level nephelometer TSI (3l) aethalometer (Magee scientific, 7l) vertically averaged sunphotometer (AERONET)Particulate concentrationsBulk mass concentration (TEOM microbalance) BC estimates derived from the aethalometer Size-resolved number(Grimm optical counter) Second SOP0 workshop, Exeter 15 May 2007

  34. METHODOLOGYCaracterization of spectral dependence sneph = Cl-a sabs = Cl-b a andbare the Angström’s exponents for scattering and absorption. They are derived directly from nephelometer and aethalometer measurements. In the case of the aethalometer, difference can be made between the values of b at short (bsw) and long ( blw) solar wavelengths. Second SOP0 workshop, Exeter 15 May 2007

  35. Jan. 15 Jan. 18 Feb.9 All data is used with particular emphasis on 3 case studies Second SOP0 workshop, Exeter 15 May 2007

  36. Examples of results Dependence of a to the BC mass fraction Second SOP0 workshop, Exeter 15 May 2007

  37. Absorption spectral dependence in the two wavelength ranges blw is particularly stable whereas bsw is much more variable and seems to be extremely sensitive to the presence of mineral dust Second SOP0 workshop, Exeter 15 May 2007

  38. Sensitivity of bsw/blw to the composition of the aerosol mixture bsw/blw is - much larger when the proportion of dust increases - lower during BB advection than during local “pollution” events Second SOP0 workshop, Exeter 15 May 2007

  39. Still to be done:Assess the exact impact of aerosol size and composition (content in iron oxides) on the magnitude of bsw Second SOP0 workshop, Exeter 15 May 2007

  40. Physico-mineralogical characterization Soil The mineral dust cycle Emission model Transport Mineral dust aerosols Mineral dust aerosols (mixing) Physico-chemical characterization Aerosol Optical model Optical properties Radiatif transfert Radiative impact over transport regions Radiative impact over source regions Second SOP0 workshop, Exeter 15 May 2007

  41. The Ca-to-Fe elemental ratio as a marker of major source region Niger (DABEX) Second SOP0 workshop, Exeter 15 May 2007

  42. LISA contribution to field observations Dry season (Jan-Feb 2006, 6 weeks) Ground-based measurements in Banizoumbou + UK BAe146 operated in Niger and Senegal Wet season (Jun-Jul 2006, 6 weeks) Ground-based measurements in Banizoumbou + F-ATR-42 operated in Niger and Benin Wet season (Sep 2006, 2 weeks) UK BAe146 operated in Senegal Second SOP0 workshop, Exeter 15 May 2007

  43. Banizoumbou, dry season Aerosol inlets, orientable to the main wind direction Second SOP0 workshop, Exeter 15 May 2007

  44. Air masses where dust plumes where found B160N3 B165N7 Courtesy: M. Harrison Second SOP0 workshop, Exeter 15 May 2007

  45. FL120 FL100 3200 feet FL120 FL100 3200 feet B161 – 23 Janvier, nord of Niger Second SOP0 workshop, Exeter 15 May 2007

  46. Second SOP0 workshop, Exeter 15 May 2007

  47. Second SOP0 workshop, Exeter 15 May 2007

  48. Second SOP0 workshop, Exeter 15 May 2007

  49. Bulk mineralogy DRX IC/ICP CBD DR SEMTEM Water soluble fraction Iron oxyde content and speciation Individual particle characteristics Analysis of inorganic fraction Air in 0.4 µm Nuclepore 90-mm SFU1 Bulk elemental composition (Na…Pb) PIXE PIGE Air out Second SOP0 workshop, Exeter 15 May 2007

  50. Organic and elemental carbon Air in 47-mm SFU2 DRI Quartz Air out BC/OC Second SOP0 workshop, Exeter 15 May 2007

More Related