Trace gases, aerosols & clouds analysed from GOME, SCIAMACHY and GOME-2. Recommendations for TROPOMI. Thomas Wagner. Satellite Group Mainz Heidelberg

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1 MPI Mainz Germany Trace gases, aerosols & clouds analysed from GOME, SCIAMACHY and GOME-2. Recommendations for TROPOMI. Thomas Wagner Satellite Group Mainz Heidelberg with contributions from: Uni- Heidelberg Germany S. Beirle, T. Deutschmann, E. Eigemeier, C. Frankenberg, M. Grzegorski, M.F. Khokhar, S. Kühl, C.Liu, T. Marbach, K. Mies, M. Penning de Vries, U. Platt, J. Pukite Retrieval Steps Data products & scientific applications Recommendations

2 Achievements during the last 10 years... - Algorithm development - Global maps & discoveries - Semi-quantitative studies: - Characterisation of sources - Investigation of (intercontinental) transport - First quantitative studies - Trend studies - Determination of source strengths

3 Set DOAS of Atmospheric satellite Absorbers algorithms Identified developed in GOME Spectra at the Satellite Group at the Institut für Umweltphysik during the last 10 years GOME & SCIA spectral properties O 3 UV OClO HCHO O 4 H 2 O O 2 Spectral albedo Satellite group: Wavelength [nm] SO 2 NO 2 BrO O 3 vis SCIAMACHY: nm => CO, CH 4, CO 2

4 CO2 CH4 CO C. Frankenberg, SRON, Liu Cheng,MPI Mainz

5 Specific problems of satellite DOAS spectroscopy Spectral structures due to sun diffuser plate cause artificial offset Solution: Use of atmospheric spectrum instead of solar spectrum OClO SCD [molec/cm²] 4E+14 3E+14 2E+14 1E+14 0E+00-1E+14 GOME OClO SCD Reihe1 Atmospheric spectrum (70 SZA) Reihe2 Direct solar spectrum Unrealistic offset Latitude [ ]

6 Use of polarisation and etalon spectra in DOAS fit) Etalon spectrum Polarisation key data

7 Use of polarisation and etalon spectra in DOAS fit) O4 absorption excluding additional spectra Residual excluding additional spectra O4 absorption including additional spectra Etalon spectrum

8 Include all relevant trace gas spectra in DOAS fit NO2 analysis excluding H2O H2O spectrum Included in GOME operational product since 1999 NO2 analysis including H2O

9 Vegetation spectra: 0.6 Conifers Decidous Grass Spectral Albedo High pass filtered albedo Wagner et al., ACP Wavelength [nm] 0.96

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11 Progress in quality of the DOAS fit (BrO) Wagner and Platt, Nature, 1998 OD Mainly caused by improved Ring correction End of 1999 OD Wavelength [nm]

12 Experiences in spectroscopy -investigate the spectral residuals -include spectra for polarisation, vegetation, etalon, etc. => carefully check results -include more than one Ring spectrum -include experimental ratio spectra -apply a consistent spectral calibration and cross section convolution -for specific cases advanced and/or iterative DOAS retrievals have to be applied (e.g. IMAP-DOAS)

13 satellite Example of radiative transfer modelling for satellite nadir geometry, 370 nm, no clouds Look from the side Rayleigh-scattering ground reflection TRACY-II Tim Deutschmann, IUP Heidelberg Look from above

14 satellite Example of radiative transfer modelling for satellite nadir geometry, 370 nm, with cloud (OD 40) from the surface to 8 km Look from the side Rayleigh-scattering ground reflection particle scattering TRACY-II Tim Deutschmann, IUP Heidelberg Look from above

15 Height dependence of the sensitivity (Box-AMF) AMF i = SCD i /VCD i Albedo: 5% Albedo: 50% e.g. Ocean e.g. Snow

16 Optical thickness: 50 Optical thickness: 50

17 Optical thickness: 4 Optical thickness: 100

18 Optical thickness: 20 Optical thickness: 100 Broken clouds

19 Influence of aerosols SCA: 1 Aerosol optical depth Aerosol layer

20 Influence of aerosols Influence of the single scattering albedo on sensitivity SCA: 1 SCA: 0.9 SCA: 0.8 Aerosol optical depth Aerosol layer

21 Experiences in radiative transfer modelling -take into account surface albedo, BDRF, totography, clouds, aerosols -3D effects for trace gases, clouds, aerosols -also polarisation effects are important! -RTM of ocean properties?

22 Example for a normalisation procedure Comparison between MOPITT & SCIAMACHY 4.00E E E E+018 MOPITT from0to5 from5to10 MOPITT SCIA (cloud fraction <5%) CO VCD 2.00E E E+018 Sahara 5.00E E Time 4.00E E+018 mopitt SCI_cloudfraction0~5 3.00E E+018 CO 2.00E E E+018 Australia Liu Cheng, C. Frankenberg 5.00E E Time

23 Achievements during the last 10 years... - Algorithm development - Global maps & discoveries - Semi-quantitative studies: - Characterisation of sources - Investigation of (intercontinental) transport - First quantitative studies - Trend studies - Determination of source strengths

24 One of our first GOME tropospheric NO2 maps Carsten Leue, 1998 Tropospheric NO2 VCD

25 Tropospheric NO2 column density SCIAMACHY, 2003/04 Steffen Beirle NO2 VCD [10 15 molec/cm²]

26 Our maps help to find cleaner working places Mainz Heidelberg Tropospheric NO2 VCD, SCIAMACHY Steffen Beirle NO2 VCD [10 15 molec/cm²]

27 Our first NO2 image from GOME-2 (only 1 day, almost global coverage) Steffen Beirle Direct transmission of data to the antenna on the roof of our institute

28 Trace gases Trop. NO 2 VCD (S. Beirle) SO 2 SCD (M.F. Khokhar) SCIAMACHY, 2003/04 GOME, HCHO SCD (T. Marbach) BrO VCD (J. Hollwedel) GOME, 1997 GOME,

29 Trace gases CO VCD C. Frankenberg, Liu Cheng H 2 O VCD T. Wagner SCIAMACHY, Jan., Feb GOME, CH 4 VCD C. Frankenberg (now at SRON) Glyoxal SCD S. Beirle SCIAMACHY, Aug.-Nov SCIAMACHY, 2004

30 Cloud Products O2 VCD T. Wagner, M. Grzegorski Cloud top height T. Wagner GOME, GOME, Ring SCD T. Wagner Cloud fraction M. Grzegorski GOME, Nov., Dec HICRU, GOME,

31 Aerosol Products UV Absorbing Aerosol index M. Penning de Vries SCIAMACHY, JAS 2004 UV Scattering Aerosol index M. Penning de Vries Preliminary results SCIAMACHY, JAS 2004

32 Surface properties Water Raman scat. T. Wagner Conifers T. Wagner, E. Eigemeier GOME, GOME, Sept Grass T. Wagner, E. Eigemeier Decidous T. Wagner, E. Eigemeier GOME, Sept GOME, Sept. 1998

33 The total vertical column density contains stratospheric and tropospheric concentrations Enhanced Tropospheric BrO concentrations during polar spring (Wagner & Platt, 1998) Bromine Explosion With assumption: trop. BrO between 0 and 500m Stratospheric offset tropospheric mixing ratio [ppt]

34 Many discoveries, here an example of strong OClO increase due to mountain lee waves (Sven Kühl, IUP-Heidelberg, JGR, 2004) Almost complete activation over an altitude range of about 10 km On the 21 st of January, a sudden increase of the OClO SCDs is seen over northern Scandinavia, the same region where strong activity of mountain waves has been reported for the same day (Dörnbrack et al., 1999).

35 Achievements during the last 10 years... - Algorithm development - Global maps & discoveries - Semi-quantitative studies: - Characterisation of sources - Investigation of (intercontinental) transport - First quantitative studies - Trend studies - Determination of source strengths

36 (Steffen Beirle, IUP Heidelberg) NO 2 Production by Biomass Burning Correlation of the NO2 VCD with Fire Counts for different regions of the world South America North America Central Africa (east) Indonesia North Australia Eastern Russia

37 Seasonal variation of the CO distribution JFM 2004, 2005 JJA 2004, 2005

38 Dependence of tropospheric BrO on latitude and time Arctic Latitude [degree] SZA > 87 => Relationship between bromine explosion and one year old sea ice Dec January February March April May June [1013 molec/cm²] Wagner et al., JGR, SZA > 87 Antarctic Latitude [degree] [1013 molec/cm²] Average Extension of Sea Ice Jun July August September October November Dec Frost Flowers

39 NO 2 Production by Lightning Lightning Activity and GOME- NO 2 for selected months 6 NO 2 [10 14 molec/cm 2 ] monthly mean values Lightning Activity [Flashes/day/pixel] (Steffen Beirle, IUP Heidelberg, Adv. Space Res., 2004) From our study (if simply extrapolated): 2.8 (0.8 14) Tg [N] / yr

40 Achievements during the last 10 years... - Algorithm development - Global maps & discoveries - Semi-quantitative studies: - Characterisation of sources - Investigation of (intercontinental) transport - First quantitative studies - Trend studies - Determination of source strengths

41 Investigation of transport processes: comparison with models Intercontinental transport of anthropogeneous NO 2 measured by GOME and modeled by FLEXPART [Stohl et al., ACP, 2003]

42 Investigation of transport processes: comparison with models Difference: NAO + -NAO - (winter ) Model results from FLEXPART GOME tropospospheric NO 2 Influence of the North Atlantic Oscillation on the tropospheric transport paths [Eckhardt et al., ACP, 2003]

43 Change of global circulation due to El-Nino Relative deviation of the GOME H2O VCD from the long year mean October 1997 March 1998 humidity Wagner et al., JGR, 2005

44 Time series of monthly anomalies of the H 2 O VCD and the temperature Wagner et al., JGR, E+21 4.E+21 3.E+21 Whole Earth Temperature anomaly [K] E+21 1.E+21 0.E+00-1.E+21-2.E+21 H2O anomaly [molec/cm²] 0.1 temp_anomaly H2O_anomaly -3.E Time -4.E+21 Tropics (30 N - 30 S) 6.00E E E E+21 temp_anomaly H2O_anomaly Trop_3030_H2O_anomaly Trop_-30 bis E E E E H2O VCD anomaly [molec/cm²] 5E+21 3E+21 1E+21-1E+21-3E+21-5E+21 y = 9.6E+21x - 3.2E+21 R 2 = Temperature anomaly [K] -1.00E E E E+21 Jan. 96 Jan. 97 Jan. 98 Jan. 99 Jan. 00 Jan. 01 Jan. 02 Jan. 03 => strong water vapour feedback Similar findings from study after Pinatubo eruption (Soden et al., 2002)

45 Correlation of the monthly anomalies of the H 2 O VCD and surface temperature Change of the H2O VCD per Kelvin [10 21 molec/cm²]

46 [%] Correlation of the monthly anomalies of the cloud fraction and surface temperature Change of the effective cloud fraction per Kelvin

47 Variation of the cloud top height with surface temperature derived from the correlation analysis Wagner et al., ACPD 2008 Change of the cloud top height per Kelvin [km]

48 Achievements during the last 10 years... - Algorithm development - Global maps & discoveries - Semi-quantitative studies: - Characterisation of sources - Investigation of (intercontinental) transport - First quantitative studies - Trend studies - Determination of source strengths

49 Trends in China Comparison of trop. NO 2 from GOME and SCIAMACHY GOME narrow mode SCIAMACHY *10 15 molecules/cm 2 S. Beirle, IUP Heidelberg

50 0.04 Global average trends O2 anomaly HICRU anomaly Monthly anomalies from 60 S to 60 N +0.2km over 7 years O2 absorption -0.80% over 7 years HICRU cloud fraction +0.33% over 7 years H2O anomaly [molec/cm ] 4E+21 0E+0-4E+21 H2O VCD +2.1% over 7 years temp. anom. [K] temperature K over 7 years Time

51 Achievements during the last 10 years... - Algorithm development - Global maps & discoveries - Semi-quantitative studies: - Characterisation of sources - Investigation of (intercontinental) transport - First quantitative studies - Trend studies - Determination of source strengths

52 Anthropogenic sources: NO x from ships Estimated NO x emissions (Endresen et al.) GOME NO 2 VCD (Meridional high-pass filter applied) Beirle et al., GRL, 2004 (similar results also from A. Richter, IUP Bremen) molec/cm 2

53 Anthropogenic sources: NO x from ships Lifetime estimation: 3.7 hours Ship emissions (Gg [N]/yr): 26 (11-81) Winter: ITCZ south, Summer: ITCZ north EDGAR: 34 Endresen: Corbett: 22/44 Beirle et al., GRL, 2004

54 Ship-emissions: SCIAMACHY NO , 2D high-passfiltered NO2 VCD Steffen Beirle AMVER ship density (% of total)

55 Ship-emissions: GOME HCHO , 1D highpass-filtered HCHO SCD (winter) Thierry Marbach AMVER ship density (% of total)

56 Comparison with model results CH 4 VCD from SCIAMACHY C. Frankenberg, IUP Heidelberg J.F. Meirink, KNMI, Utrecht Science, March 2005 SCIAMACHY, Aug-Nov 2003 TM3 model, Aug-Nov 2003

57 Difference SCIAMACHY Model, Aug-Nov 2003 C. Frankenberg, IUP Heidelberg The largest differences can be seen in tropical broadleaf evergreen forests Science, March 2005 In agreement with recent findings of a new CH 4 source from plants under aerobic conditions Keppler et al., Nature 2006 MODIS Enhanced Vegetation Index

58 Summary of the last 10 years:...the new satellite sensors exceeded the expectations: The global distribution of several tropospheric trace gases could be detected, many unexpected observations New insight in distribution and characteristics of sources New insights in atmospheric transport pathways Trend studies Global inverse modelling => New View!

59 Recommendations for TROPOMI Avoid polarisation sensitivity Avoid spectral structures caused by diffuser plate (or other parts) Avoid undersampling (IR channel) Enable the use one Fraunhofer (solar) spectrum for all observations => scanning mirror concept?

60 Recommendations for TROPOMI Include additional IR channel (~1600nm for CO2 and CH4) (also for cloud water phase) Decide which spatial resolution is really required, based on chemical model data and radiative transfer modelling Start UV channel at 300nm (SO2 retrieval), NIR channel at <610nm (O4, vegetation spectra)

61 Many thanks for your attention! Satellite Group April 2007