1. Institut für Umweltphysik/Fernerkundung Physik/Elektrotechnik Fachbereich 1 Status of SQWG activities H. Bovensmann, G. Lichtenberg, R. Snel, C. Lerot, T Fehr (on behalf of SQWG) SADDU Meeting, 10.-11.3.2009, SRON, Utrecht

2. Overall Processor Schedule Currently active processors: L1 version 6.03, L2 version 3.01 Planned (2008) to be activated in 2008: L1 v7, L2 v4 Planned (2008) to be activated in 2008: L1 v8, L2 v5 But: IPF L1 version 7 implementation slowed down in 2008, due to problems when porting from AIX to LINUX IPF L1 version 7 will now be activated soon (tbc ESA) Level 1 version 8 baseline verified and delivered to ESA Level 2 version 4 was delivered and was accepted in 2008 Level 2 version 5 currently under verification, delivery April 2009 ESA decided not to have two Level 2 versions shortly after each other, consequently –Level 2 version 4 will not be activated (only fall back). –Level 2 version 5 will be activated in May 2009 (tbc ESA)

3. Status Baseline Update 2008 – Level 1 „Version 7“ Level 0-1 („Version 7“): – Straylight Matrix in Channel 2 – Limb mesosphere/thermosphere measurement written to Limb MDS – Correction of wrong scanner encoder values – Baseline finished and accepted – Implementation after AIX to Linux switch in ground segment Next Version (v.8/9) candidates: – Straylight Matrix channel 3-8 – Update of Key Data – Improved dark current correction ch. 8

4. Status Baseline Update 2008 – Level 1 „Version 7“ SciCal 2.0: – Update of the Dead&Bad Pixel Mask – better validation time configuration SciaL1c version 2.1: – M-factor correction with and without automatic selection added (M-factor data base available from IUP-UB) – Baseline finished, – Tool is available on the ESA web page since October – Windows version will soon be delivered

5. Baseline Update 2008 – Level 2 „Version 4“ Level 1b-2 (details see last SADDU): – Improved AAI algorithm – Nadir O3 and AAI uses degradation correction (m- factors) – Nadir NO 2 uses ASM as reference spectra – New: Nadir BrO SC and SO2 SC – Improved Limb O 3 and NO 2 – Baseline („Version 4“) finished and accepted – FAT succesfully finished in October – Ready for activation

6. Baseline Update 2009: Overview L1b-2 “Version 5” New Products: –Nadir SO2 total columns –Nadir BrO total columns –Nadir H2O total columns –Nadir xCO columns –Nadir OClO slant columns –Limb Cloud Flag Product –Limb BrO profile

7. Status L1b-2 Evolution towards “L2 Version 5” O 3 Total Colum –No changes in algorithm (GDP4/GDOAS derived) –Is the temporal trend in O3 TC minimised by using m-factors and straylight correction channel 2? –Verification ongoing NO2 Total Column –No changes –Verification OK AAI –No changes –Verification OK Cloud Products –New minimum reflectance data base –Verification OK

8. Status L1b-2 Evolution towards “L2 Version 5” SO 2 from Slant to Total Column – Introduction of two AMF schemes and thereby two VC products (boundary layer, volcanic) – Verification ongoing BrO from Slant to Total Column – Implementation of AMF using BIRA climatological database – Verification ongoing OClO slant column – Verification OK H 2 O VC – AMC-DOAS approach implemented – Verification OK xCO – BIRRA approach implemented – verification ongoing

9. OClO SC Verificaton

10. Level 1b-2 Evolution towards “L2 Version 5” Limb Cloud Cloud Flagging Algorithm Implemented Verification OK Limb BrO Algorithm implemented Retrieval starts above cloud Verification OK (substantial scatter in single profile product (as expected) Limb Ozone No change in algorithm Retrieval starts above cloud Background aerosol used (tbc) Verification ongoing Limb NO2 No change in algorithm Retrieval starts above cloud Verification OK

11. Limb Cloud Flag New limb cloud MDS introduced: FLAG: 0 = no cloud 1 = patially cloudy 2 = fully cloudy 3 = bad data MAXVAL: maximum value of the color index ratio, MAXHEIGHT: tangent height (in km) where MAXVAL is found MAXHEIGHTIDX: index of MAXHEIGHT each for three different cloud types WCL: normal water clouds, ICL: ice clouds and PSC: polar stratospheric clouds.

12. Limb BrO High scatter between single retrievals. Between 20 and 32 km the average difference is typically within 20 - 30%.

13. Limb O3 using cloud flag Comparison done by A. van Gijsel, RIVM

14. Summary L2 Version 4 & 5 Nadir Improvements – Improved AAI algorithm (uses 1st order degradation correction) – Improved Nadir O3 (degradation correction, stray light) – Nadir NO 2 uses ASM as reference spectra – Cloud Fraction uses SCIA minimum reflectance data base Nadir New – BrO SC & VC (tbc) – SO2 SC & VC (tbc) – OClO SC – H2O VC – xCO

15. Summary L2 Version 4&5 Limb Improvements – O3 profiles (retrieval above clouds, background aerosol) – NO2 profiles (retrieval above clouds) Limb New – Limb cloud flag information – BrO profile

16. Institut für Umweltphysik/Fernerkundung Physik/Elektrotechnik Fachbereich 1 Potential Activities Year 3-4 (2009 – 2011) For Discussion Purposes Only! Currently not „contracted“

17. Note Current SQWG contract is running until spring 2009 Agencies (ESA/NIVR/DLR) intends continuation Team received RfQ/SoW beginning of March 2009 Proposed activities were iterated with SADDU and SSAG in 2008 All proposed improvements are preliminary w.r.t. to continuation of the involved contracts/funding lines

18. Overall Goals 2009 ff. The main goal for SQWG Year 3-4 (ff.) should be, to establish L1 and L2 data quality of the full SCIAMACHY data set, which allows substantial contributions to long term atmospheric data sets in the areas of: –the development of the O 3 layer –global air pollution –Global Greenhouse gas observations –Solar-Terrestrial interactions In addition, the data set shall allow to investigate new scientific methods and products.

19. Level 1 Improvement & Evolution – Draft Plan

20. Improving data products based on outcome of validation activities Adaptation of Level 1-2 algorithms w.r.t. sensor degradation Adaptation of Level 1-2 algorithms w.r.t. orbit changes beyond 2010 Level 2 Year 3-4: General

21. Level 2 evolution 2009 – 2010 – Draft Plan

22. Institut für Umweltphysik/Fernerkundung Physik/Elektrotechnik Fachbereich 1 The End