ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-8-4517-2008 Comparison of OMI ozone and UV irradiance data with ground-based measurements at two French sites Buchard V. 1 Brogniez C. 1 Auriol F. 1 Bonnel B. 1 Lenoble J. 1 2 Tanskanen A. 3 Bojkov B. 4 5 Veefkind P. 6 Laboratoire d'Optique Atmosphérique, Université des Sciences et Technologies de Lille, France Interaction Rayonnement Solaire Atmosphère, Université Joseph Fourier de Grenoble, France Finnish Meteorological Institute, Helsinki, Finland Goddard Earth Sciences and Technology Center, University of Maryland, Baltimore County, Baltimore, Maryland, USA Atmospheric Chemistry Dynamics Branch, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA Royal Netherlands Meteorological Institute, De Bilt, The Netherlands 05 08 2008 8 16 4517 4528 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/8/4517/2008/acp-8-4517-2008.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/8/4517/2008/acp-8-4517-2008.pdf

Ozone Monitoring Instrument (OMI), launched in July 2004, is dedicated to the monitoring of the Earth's ozone, air quality and climate. OMI is the successor of the Total Ozone Mapping Spectrometer (TOMS) instruments and provides among other atmospheric and radiometric quantities the total column of ozone (TOC), the surface ultraviolet (UV) irradiance at several wavelengths, the erythemal dose rates and the erythemal daily doses. The main objective of this work is to compare OMI data with data from ground-based instruments in order to use OMI products (collection 2) for scientific studies. The Laboratoire d'Optique Atmosphérique (LOA) located in Villeneuve d'Ascq (VdA) in the north of France performs solar UV measurements using a spectroradiometer. The site of Briançon in the French Southern Alps is also equipped with a spectroradiometer operated by Interaction Rayonnement Solaire Atmosphère (IRSA). The OMI total ozone column data is obtained from the OMI-TOMS and OMI-DOAS algorithms. The comparison between the TOC retrieved with ground-based measurements and OMI-TOMS data shows good agreement at both sites for all sky conditions with a relative difference for most of points better than 5%. For OMI-DOAS data, the agreement is generally better than 7% and these data show a significant dependence on solar zenith angle. Comparisons of spectral UV on clear sky conditions are also satisfying with relative differences smaller than 10% except at solar zenith angles larger than 65°. On the contrary, results of comparisons of the erythemal dose rates and erythemal daily doses for clear sky show that OMI overestimates surface UV doses at VdA by about 15% and that on cloudy skies, the bias increases. At Briançon, such a bias is observed if data corresponding to snow-covered surface are excluded.

 References Arola, A., Kazadzis, S., Krotkov, N., Bais, A., Groebner, J., and Herman, J. R.: Assessment of TOMS UV bias due to absorbing aerosols, J. Geophys. Res., 110, D23211, doi:10.1029/2005JD005913, 2005. Bais, A., Gardiner, B., Slaper, H., et al.: SUSPEN intercomparison of ultraviolet spectroradiometers, J. Geophys. Res., 106, D12, 12 509–12 525, 2001. Balis, D., Kroon, M., Koukouli, M. E., Brinksma, E. J., Labow, G., Veefkind, J. P., and McPeters, R. D.: Validation of Ozone Monitoring Instrument total ozone column measurements using Brewer and Dobson spectrophotometer ground-based observations, J. Geophys. Res., 112, D24S46, doi:10.1029/2007JD008796, 2007. Bhartia, P. K. and Wellemeyer, C.: TOMS-V8 Total O<sub>3</sub> algorithm, in: OMI ozone product ATBD Volume II, NASA Goddard Space Flight Center, Greenbelt, MD, USA, 2002. Bernhard, G. and Seckmeyer, G.: Uncertainty of measurements of spectral solar UV irradiance, J. Geophys. Res., 104, 14 321–14 345, 1999. Brogniez, C., Hou\"et, M., Siani, A. M., Weihs, P., Allaart, M., Lenoble, J., Cabot, T., de La Casinière, A., and Kyro, E.: Ozone column retrieval from solar UV measurements at ground level: effects of clouds and results from six European sites, J. Geophys. Res., 110, D24202, doi:10.1029/2005JD005992, 2005. Brogniez, C., Buchard, V., and Auriol, F.: Validation of UV-visible aerosol optical thickness retrieved from spectroradiometer measurements, Atmos. Chem. Phys. Discuss., 8, 3895–3919, 2008. Cede, A., Luccini, E., Nuñez, L., Piacentini, R. D., Blumthaler, M., and Herman, J. R.: TOMS-derived erythemal irradiance versus measurements at the stations of the Argentine UV Monitoring Network, J. Geophys. Res., 109, D08109, doi:10.1029/2004JD004519, 2004. Diffey, B. and McKinlay, A. F.: A reference action spectrum for ultraviolet induced erythema in human skin – human exposure to UV radiation: risks and regulations, Elsevier, NY, USA, 83–87, 1987. Gröbner, J., Blumthaler, M., Kazadzis, S., Bais, A., Webb, A., Schreder, J., Seckmeyer, G., and Rembges, D.: Quality assurance of spectral solar UV measurements: results from 25 UV monitoring sites in Europe 2002 to 2004, Metrologia, 43, S66–S71, doi:10.1088/0026-1394/43/2/S14, 2006. Herman, J. R., Krotkov, N., Celarier, E., Larko, D., and Labow, G.: Distribution of UV radiation at the Earth's surface from TOMS-measured UV-backscattered radiances, J. Geophys. Res., 104, 12 059–12 076, 1999. Hou\"et, M. and Brogniez, C.: Ozone column retrieval from solar UV irradiance measurements at ground level: sensitivity tests and uncertainty estimation, J. Geophys. Res, 109, D15302, doi:10.1029/2004JD004703, 2004. Kalliskota, S., Kaurola, J., Taalas, P., Herman, J. R., Celarier, E., and Krotkov, N.: Comparison of the daily UV doses estimated from Nimbus7/TOMS measurements and ground-based spectroradiometric data, J. Geophys. Res., 105, 5059–5067, 2000. Kazantzidis, A., Bais, A. F., Groebner, J., Herman, J. R., Kazadizis, S., Krotkov, N., Kyro, E., den Outer, P. N., Garane, K., Gorts, P., Lakkala, K., Meleti, C., Slaper, H., Tax, R. B., Turunen, T, and Zerefos, C. S.: Comparison of satellite-derived UV irradiances with ground based measurements at four European stations, J. Geophys. Res., 111, D13207, doi:10.1029/2005JD006672, 2006. Kroon, M., Veefkind, J. P., Sneep, M., McPeters, R. D., Bhartia, P. K., and Levelt, P. F.: Comparing OMI-TOMS and OMI-DOAS total ozone column data, J. Geophys. Res., 113, D16S28, doi:10.1029/2007JD008798, 2008. Krotkov, N. A., Bhartia, P. K., Herman, J., Ahmad, Z., and Fioletov, V.: Satellite estimation of spectral surface UV irradiance – 2: Effecct of horizontally homogeneous clouds and snow, J. Geophys. Res., 106, 11 743–11 759, 2001. Krotkov, N. A., Herman, J., Bhartia, P. K., Seftor, C., Arola, A., Kaurola, J., Kalliskota, S., Taalas, P., and Geogdzhaev, I.: Version 2 TOMS UV algorithm: problems and enhancements, Opt. Eng., 41, 3028–3039, 2002. Levelt, P. F., van den Oord, G. H. J., Dobber, M. R., Mälkki, A., Visser, H., de Vries, J., Stammes, P., Lundell, J. O. V., Saari, H.: The Ozone Monitoring Instrument, IEEE T. Geosci. Remote, 44(5), 1093–1101, 2006a. Levelt, P. F., Hilsenrath, E., Leppelmeier, G. W., van den Oord, G. B. J., Bhartia, P. K., Tamminen, J.: Science objectives of the ozone monitoring instrument, IEEE T. Geosci. Remote, 44(5), 1199–1208, 2006b. McKenzie, R. L., Seckmeyer, G., Bais, A. F., Kerr, J. B., and Madronich, S.: Satellite retrievals of erythemal UV dose compared with ground-based measurements at northern and southern midlatitudes, J. Geophys. Res., 106, 24 051–24 062, doi:10.1029/2001JD000545, 2001. Paur, R. J. and Bass, A. M.: The ultraviolet cross sections of ozone – 2: Results and temperature dependence, in: Atmospheric Ozone, Proceedings of the Quadriennal Ozone Symposium, Haldikiki, Greece, 3–7 September 1984, 611–616, 1985. Slaper, H., Reinen, H., Blumthaler, M., Huber, M., and Kuik, F.: Comparing ground-level spectrally resolved solar UV measurements using various instruments: a technique resolving effects of wavelength shift and slit width, Geophys. Res. Lett., 22(20), 2721–2724, 1995. Stamnes, K., Tsay, S. C., Wiscombe, W. J., and Jayaweera, K.: Numerically stable algorithm for discrete ordinate method radiative transfer in multiple scattering and emiting layered media, Appl. Opt., 27, 2502–2509, 1988. Stamnes, K., Slusser, J. R, and Bowen, M.: Derivation of total ozone abundance and cloud effects from spectral irradiance measurements, Appl. Opt., 30, 4418–4426, 1991. Tanskanen, A.: Lambertian surface albedo climatology at 360 nm from TOMS data using moving time-window technique, in "Proceedings of the 20th Quadriennal Ozone Symposium", Kos, Greece, 1–8 June 2004, 1159–1160, 2004. Tanskanen, A., Krotkov, N. A., Herman, J. R., and Arola, A.: Surface Ultraviolet Irradiance from OMI, IEEE T. Geosci. Remote, 44(5), 1267–1271, 2006. Tanskanen, A., Lindfors, A., Määttä, A., Krotkov, N., Herman, J., Kaurola, J., Koskela, T., Lakkala, K., Fioletov, V., Bernhard G., McKenzie, R., Kondo, Y., O'Neill, M., Slaper, H., den Outer, P., Bais, A., and Tamminen J.: Validation of daily erythemal doses from ozone monitoring Instrument with ground-based UV measurement data, J. Geophys. Res., 112, D24S44, doi:10.1029/2007JD008830 2007. Veefkind, J. P., de Haan, J. F., Brinksma, E. J., Kroon, M., and Levelt, P. F.: Total ozone from the ozone monitoring instrument (OMI) using the DOAS technique, IEEE T. Geosci. Remote, 44(5), 1239–1244, 2006. WMO: Scientific assessment of ozone depletion 2006, WMO Report No. 50, World Meteorological Organization, Geneva, Switzerland, 2007.