1. First impressions on Brewer processing methods survey Tomi Karppinen COST WG1/WG2 meeting Manchester, 27. September 2013

2. Replies By 24th September, 9 replies Arosa (Swizerland), Rome U (Italy), ARPA Valle d’Aosta (Italy), Athens (Greece), RMIB (Belgium), SMHI (Sweden), IPMA (Portugal), Manchester U (Engand), FMI (Finland) Low overall cover but very helpful

3. Ozone software Variety of processing tools ◦ Brewer operating software (for realtime for many, for some no further processing) ◦ O3Brewer (2 final, 1 for daily diagnostics) ◦ Brewer processing software, BPS by Env. Canada (2 final) ◦ Self developed software (4, in C, Excel(VBA, Modula2) and Matlab)

4. Ozone processing levels Raw collected and archived for everyone? Basic processing, Brewer operating softw. Corrections and notes ◦ ETC correced with SL-test (smooth vs. step) ◦ Quality flagged (std, unrealistic, clouds) End products ◦ Daily mean/selected daily value ◦ All measurements ◦ Ds, zs, fz, gi ?

5. UV software Not processed regularly(3) Rd_ux3d (2) UVBrewer (2) SHICrivm (4, for wavelength shift and spectral anomaly) Self developed (5, in perl, Matlab, IDL and C)

6. UV processing levels Raw counts Irradiance spectrum Corrections for ◦ Temperature ◦ Cosine error ◦ Stray light (subtract short wl intensity, 5 wavelengths?) ◦ Wavelength shift and spikes End products ◦ Spectra ◦ Daily dosages (differently weighted) ◦ UV-index ◦ More?

7. AOD software Not processed regularly or at all (4) Brewer operating sw (2) O3Brewer (2) O3Baod (1) Self developed scripts (2, in C and Fortran)

8. AOD processing levels Brewer operating sw (very basic?) Own software can take into account ◦ Cloud screening ◦ Realistic Rayleigh scatter ◦ Calibrated ETC ◦ Earth-Sun –distance ◦ Value and value change screening as unrealistic

9. Umkehr Regular measurements (3/9) Not regularly processed Software ◦ C-code by McElroy ◦ O3Bumkehr

10. NO 2 For Mk IV only? N2ds measurements on visible wavelegths Processing software by Diemoz

11. SO 2 Rarely processed Detectable only in urban enviroments? ◦ Volcanic ash clouds & fires? Calibration constants up to date? Attention needed?

12. Conclusions Diverse practises Concentration areas, for example ◦ Mk IV NO2 ◦ Belgium & Italy AOD Everyone does Ozone, but at different levels? Data coherence? ◦ Algorithms, boundary conditions, corrections, calibration frequency, schedules …

13. Future? Recommendations and practises or tools and software? ◦ Own routines vs. new ones Software flexibility ◦ Platform for new procedure tryout, needs to be accessible for modification ◦ New software or build on some existing software? Can we reach the same level if there are no possibilities to process complitely due to lack of supporting information (cloud screening, ozonesondes, response tracking etc)