Anna Serdyuchenko, Victor Gorshelev, Mark Weber John P. Burrows University of Bremen, Institute for Environmental Physics OSU, Columbus OH, USA1

Atmospheric species detection:  Remote sensing instruments;  Available databases for the reference data;  Modern demands on the O3 absorption cross-sections. Results:  Ozone spectra in UV /VIS/IR;  Comparison with existing datasets. OSU, Columbus OH, USA2

important for air quality study, Montreal Protocol monitoring of ozone depleting substances, ozone-climate interaction etc several decades are only available by combining datasets from multiple sensors (satellite spectrometers and ground based instruments).SpectrometerOperation Dobson, BrewerGround based, since 1925 SBUV1978 – 1990, SAGE , , , 2014-? GOME TOMS OSIRIS now SCIAMACHY GOMOS OMI now GOME now, 2014-?, 2016-? OSU, Columbus OH, USA3

I, I 0 transmitted intensity with or without ozone L absorption path length N ozone density 4

OSU, Columbus OH, USA5 Nowadays, spectral channels of the satellites- and ground based-instruments measuring ozone and other trace gases cover a wide spectral range from near UV to the visible and IR. Ozone absorption spectrum in near UV – near IR affects channels for detection of other traces gases, aerosols and clouds.

OSU, Columbus OH, USA6

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9 The spectral resolution of diverse ozone observing instruments changes: with wavelength from the UV to the near IR; from channel to channel for each instrument.

OSU, Columbus OH, USA InstrumentFWHM, nm Dobson1 - 3 Brewer0.6 TOMS1 OMI OSIRIS1 SBUV1.13 SAGE III1.2 – 2.5 Data setFWHM, nmCalibrationUncertainty, % GOME FM, Burrows et al., 330 nmabsolute2.6 – 4.6 SCIAMACHY FM, Bogumil et al., 330 nmUsing BP3.1 Paur and Bass, 1985 (HITRAN 2008)<0.025 nmUsing Hearn2.3 Malicet, Brion, Daumont nmabsolute (1.8 – 4.5) This work, nmabsolute2 – 3% 10

Huggins Hartley Chappuis Wulf OSU, Columbus OH, USA11

Huggins Hartley Chappuis Wulf OSU, Columbus OH, USA12 Temperature dependence Band-integrated cross-sections Scaling factors, wavelength shifts and difference Agreement within experimental uncertainties for most of the spectral regions (excluding nm and 950 – 1050 nm) Databases compared: GOME, SCIAMACHY, Voigt et al, BP (HITRAN 2008), BMD Comparison between cross-sections is not the same thing as comparison between retrievals results!

OSU, Columbus OH, USA13 New data in Hartley band New data agree with BMD; Temperature dependence within 1%

New data in Huggins Band OSU, Columbus OH, USA14 New data agree with BMD; Temperature dependence: second order polynomial

New data in Huggins band: wavelength shift, scaling factor, difference OSU, Columbus OH, USA15

New data and SCIAMACHY dataset in Chappuis Band OSU, Columbus OH, USA16 New data agree with measurements on the single wavelengths; Temperature dependence within 1% and less

New data and SCIAMACHY dataset in Wulf Band OSU, Columbus OH, USA Weak absorption, measurements are very sensitive to the baseline and S/N, low accuracy and precision -> FTS upgrade is needed; Temperature dependence in NIR; Region is interesting for future missions (SAGE III) 17

Data setTemperatures, K Resolution, nm Wavelength, nm GOME FM Burrows et al., 1999 ‏ nm230 – 800 SCIAMACHY FM Bogumil et al., nm230 – 1070 GOME2 FM Spietz et al., nm240 – 790 Paur and Bass, <0.025 nm(?) ‏ 245 – 345 Malicet, Brion, Daumont nm 195 – 345 UV-FTS Voigt et al., nm230 – 850 Serdyuchenko, Gorshelev nm230 – OSU, Columbus OH, USA18

Summer 2009: Start of serial measurements Summer 2010-Winter 2011: Absolute calibration Spring 2011: Retrievals and tests Spring 2012: Publications preparation Summer 2012: data release Starting from summer 2012: Feedback from ozone investigating groups and organizations OSU, Columbus OH, USA19 The total ozone columns retrieved from GOME-2 and SCIAMACHY satellites are in good agreement with the amounts retrieved by the current data Data were recommended for ozone retrievals using spectra obtained by OMI and ground based instruments in the recent Master study of Albert Oude Nijhuis (Royal Netherlands Metrological Institute)

 CH4 line parameters investigation (winter );  Lab upgrade: dual-channel FT spectrometer (summer 2012);  Possible new measurements (starting from autumn 2012) : Ozone: NIR and 10 mkm ; SO2 for UV sensors (320 nm). OSU, Columbus OH, USA20

Work is supported by European Space Agency Thank you for attention ! OSU, Columbus OH, USA21

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OSU, Columbus OH, USA23

Retrieval tests using the new ozone cross-section data  The new experimental cross-section data are tested in total ozone retrieval of GOME-2 and SCIAMACHY.  The data have to be convolved to GOME-2 and SCIAMACHY slit function.  The total ozone columns retrieved from GOME-2 and SCIAMACHY satellites are in good agreement with the amounts retrieved by the current data, +1% and +2% respectively.  fit residuals (RMS) for GOME-2 and SCIA similar to satellite FM. GOME-2 SCIAMACHY

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OSU, Columbus OH, USA26

Upgraded cooling system Max possible cooling: down to 193 K Temperature stabilization at intermediate points with step of 10 K Reliable temperature determination (better than 5% accuracy) : Pt sensors, spectroscopic method Upgraded gas pre-cooler features 10 meter Cu pipe bound to fit cryostat bath guaranteed cooling down to cryostat vessel temperature; ozone-friendly internal coating minimal heat gain between precooler ant test cell Sensors: Precooler:  Goals and strategy  Re-analysis  Experimental set-up  Serial measurements and preliminary results OSU, Columbus OH, USA27

Cooling: double jacket (vacuum/ethanol) cell, cryostat with pre-cooling: 10 m Cu tube coil with inert coating Control: O2-A band at 760 nm, experimental spectrum: from FTS at 0.5 cm, model spectrum: using HITRAN line parameters accuracy: 5 K or better Introduction and motivation Experimental set-up Analysis of sources of uncertainty Results and Outlook OSU, Columbus OH, USA28

 Relative to NIST database Introduction and motivation Experimental set-up Analysis of sources of uncertainty Results and Outlook OSU, Columbus OH, USA29