1. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD and first preliminary results of the aerosol campaign. RMI December 6 th 2006. Validation of the method to retrieve the Aerosol Optical Depth from the Brewer Ozone measurements First preliminary results of the aerosol campaign at Uccle

2. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Validation of the method to retrieve the Aerosol Optical Depth from the Brewer Ozone measurements Anne Cheymol, Hugo De Backer, Weine Josefsson and René Stübi anne.cheymol@oma.be Cheymol et al., jgr, 2006

3. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Overview 1. Introduction 2. The Brewer instrument 3. Description of the method 4. Results  Measurements sites  Impact of the neutral density filter on AOD  Validation of the AOD between a Brewer and a sunphotometer  Comparisons between Brewer at the same place 5. Conclusions and perspectives

4. Role of aerosol particles Most aerosol particles’s knowledge is in VIS and IR and not in UV Important role in climate forcing  UV-B irradiance reduction by about 5-35% Impact on Human health Royal Meteorological Institute of Belgium 3 Validation of the method to retrieve the AOD. RMI December 6 th 2006.

5. Anthropogenic origin Polluted day on January 28 th 2006 Royal Meteorological Institute of Belgium 3 Validation of the method to retrieve the AOD. RMI December 6 th 2006. Photo by A. Delcloo and A. Mangold smoke Clear day on November 9 th 2006

6. Natural origin of aerosol Sea salt ejected from the sea in the air Royal Meteorological Institute of Belgium 3 Validation of the method to retrieve the AOD. RMI December 6 th 2006. Photo by Plisson

7. Natural origin of aerosol Pollen Royal Meteorological Institute of Belgium 3 Validation of the method to retrieve the AOD. RMI December 6 th 2006. Clean roof Photo from the web

8. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Overview 1. Introduction 2. The Brewer instrument 3. Description of the method 4. Results  Measurements sites  Impact of the neutral density filter on AOD  Validation of the AOD between a Brewer and a sunphotometer  Comparisons between Brewer at the same place 5. Conclusions and perspectives

9. Royal Meteorological Institute of Belgium 11 Validation of the method to retrieve the AOD. RMI December 6 th 2006 280-363 nm 306-320 nm

10. Validation of the method to retrieve the AOD. RMI December 6 th 2006 Royal Meteorological Institute of Belgium 9 Zenith angle = z a sunset Rotation of the instrument during the day 12H AfternoonMorning

11. Royal Meteorological Institute of Belgium 10 Summary of the Brewer measurements 5 measurements/4mns every 30mns Automatic rotation during the day to follow the sun No cloud  direct sun measurement 25°  z a  70 ° for one day at Uccle Validation of the method to retrieve the AOD. RMI December 6 th 2006

12. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Aerosol Optical Depth = attenuation of solar radiation by aerosol particles Direct Sun radiation at 306, 310, 313, 316 and 320 nm

13. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 20068 Over 100 Brewer stations

14. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Overview 1. Introduction 2. The Brewer instrument 3. Description of the method 4. Results  Measurements sites  Impact of the neutral density filter on AOD  Validation of the AOD between a Brewer and a sunphotometer  Comparisons between Brewer at the same place 5. Conclusions and perspectives

15. Royal Meteorological Institute of Belgium Signal received by the Brewer S( ) = K( ) I o ( ) exp[ D o3 ( ) + D ray ( ) + D aer (  sec(z a ) ) ] 13 Validation of the method to retrieve the AOD. RMI December 6 th 2006 Aerosol particlesMoleculeOzone

16. Royal Meteorological Institute of Belgium ln[ S( ) ]-D o3 - D ray = ln[ K( ) I o ( ) ]-  ( ) * sec(z a ) + Y = A * X + B Langley plot method 14 Validation of the method to retrieve the AOD. RMI December 6 th 2006

17. Royal Meteorological Institute of Belgium Langley plot method 18/06/00 for 306.3 nm Y = ln[S( )] - D o3 - D ray A = -  ( ) *X = sec(za) +B = ln[K( )I o ( )] 17 5 DS scans/4mn Validation of the method to retrieve the AOD. RMI December 6 th 2006

18. Selection of clear days for the Langley Plot Method 1.ozone stdev for individual DS measurements < 2.5 DU  z a per day  20° 3.number of good data per day  50 4.Distance between each point and the regression line < 4 (Y unit) 5.Daily mean absolute deviation from the LP regression line < 0.055 (Y units) Royal Meteorological Institute of Belgium 16 Validation of the method to retrieve the AOD. RMI December 6 th 2006

19. Royal Meteorological Institute of Belgium 4 Validation of the method to retrieve the AOD. RMI December 6 th 2006. Calibration factor Calibration factor = intersect of the fitting line  B in the equation Y=AX+B Based on the 59 best fit of the solar irradiance intensity Average of the 59 calibration factors error of about 0.2% constant during the whole period at Uccle, can change in function of Brewer

20. Royal Meteorological Institute of Belgium 5 Validation of the method to retrieve the AOD. RMI December 6 th 2006. Summary of the method

21. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Overview 1. Introduction 2. The Brewer instrument 3. Description of the method 4. Results  Impact of the neutral density filter on AOD  Validation of the AOD between a Brewer and a sunphotometer  Comparisons between Brewer at the same place 5. Conclusions and perspectives

22. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Where?

23. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. 320 nm 368 nm sunphotometer Time difference max = 3 min

24. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Filters impact on AOD c = 0.87 b = 0.80 ± 0.011 a = -0.08 ± 0.004 c = 0.98 b= 0.85 ± 0.004 a= 0.02 ± 0.0014 N = 1718 Standard filters N = 1934 Real filters Errors

25. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Where?

26. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. 320 nm 368 nm sunphotometer Hourly mean AOD compared for 2002

27. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Comparison Arosa/Davos c = 0.62 b = 0.56 ± 0.04 a = 0.02 ± 0.0006 N = 335

28. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Overview 1. Introduction 2. The Brewer instrument 3. Description of the method  Physical equation  Langley plot method 4. Results  Impact of the neutral density filter on AOD  Validation of the AOD between a Brewer and a sunphotometer  Comparisons between Brewer at the same place 5. Conclusions and perspectives

29. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Where?

30. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Uccle 2002-2005 N = 5781 c = 0.98 b= 1.02 ± 0.003 a= 0.06 ± 0.001

31. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Arosa 2004 N = 2771 N = 3169 c = 0.98 b= 0.98 ± 0.003 a= -0.04 ± 0.001 c = 0.94 b= 0.98 ± 0.006 a= 0.03 ± 0.002

32. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Arosa 2004 N = 5290 c = 0.99 b= 0.98 ± 0.002 a= -0.02 ± 0.0005

33. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Summary of the comparisons Brewer016040072 178 0.98 1.02 0.06 156 0.94 0.98 0.03 0.98 0.98 -0.04 072 0.99 0.98 -0.02

34. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Overview 1. Introduction 2. The Brewer instrument 3. Description of the method  Physical equation  Langley plot method 4. Results  Impact of the neutral density filter on AOD  Validation of the AOD between a Brewer and a sunphotometer  Comparisons between Brewer at the same place 5. Conclusions and perspectives

35. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Summary 1. Important role of the filter of the Brewer spectrophotometer on the accuracy of AOD 2. High level of confidence of the method used to retrieve the AOD:  correlation coefficient > 0.94  slope ~ 1  Intercept max = 0.06 3. Validation of the Langley plot method with a comparison between Brewer spectrophotometer and a sunphotometer

36. Royal Meteorological Institute of Belgium Validation of the method to retrieve the AOD. RMI December 6 th 2006. Perspectives 1. Application of the method at different Brewer stations 2. Determination of relation between different aerosol parameters: AOD, ssa, type, size and backtrajectories analysis

37. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. First preliminary results of the aerosol campaign at Uccle Anne Cheymol, Willy Maenhaut, Alexander Mangold, Hugo De Backer, Jan Cafmeyer, Andy Delcloo, René Lemoine and Roeland Van Malderen

38. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Overview 1. Objectives of the campaign 2. The instruments and the first preliminary results 3. Perspectives

39. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Objectives Determination of the relations between AOD, size and type of aerosol particles and air mass origin

40. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Sampling Filter by Delcloo and Mangold Inlet PM10 PM2.5

41. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Ratio PM2.5/PM10

42. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Coarse particle PM10-PM2.5 Fine particles PM2.5 20% anthropogenic source 61% anthropogenic source

43. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. TEOM inlet

44. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Mass of PM2.5 01/02 Mean = 15.4 ug/m3 03/01

45. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. 01 February 2006 03/01 01/02

46. Royal Meteorological Institute of Belgium 3 Aerosol Campaign at Uccle. RMI December 6 th 2006. Photo by A. Delcloo and A. Mangold smoke 28/0109/11 20 ug/m3 50 ug/m3

47. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Aethalometer Mass of Black Carbon

48. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Perspectives 1 1. Determination of the relation between AOD, mass and type of particle and the air mass origin 2. Aerosol studies is foreseen within the Antarctic project with BIRA and Ghent University

49. Royal Meteorological Institute of Belgium Aerosol Campaign at Uccle. RMI December 6 th 2006. Most important perspectives snoepjes

50. Royal Meteorological Institute of Belgium Antarctic project. RMI December 6 th 2006. The antarctic project

51. Royal Meteorological Institute of Belgium Antarctic project. RMI December 6 th 2006. RMI Ozone/UV/aerosol group BIRA M. Van Roozendael, M. De Mazière, C. Hermans, D. Gillotay, C. Depiesse, C. Muller,D. Bolsee Ugent W. Maenhaut and J. Cafmeyer Members of the project