Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 8 1 2008 10.5194/acpd-8-4001-2008 http://www.atmos-chem-phys-discuss.net/8/4001/2008/ http://www.atmos-chem-phys-discuss.net/8/4001/2008/acpd-8-4001-2008.html http://www.atmos-chem-phys-discuss.net/8/4001/2008/acpd-8-4001-2008.pdf 4001 4016 2008-02-26 Retrieval of stratospheric aerosol size information from OSIRIS limb scattered sunlight spectra A. E. Bourassa adam_bourassa@ssaihq.com D. A. Degenstein E. J. Llewellyn Science Systems and Applications, Inc., Hampton, VA, USA Institute of Space and Atmospheric Studies, University of Saskatchewan, Saskatoon, Canada Recent work has shown that the retrieval of stratospheric aerosol vertical profiles is possible using limb scattered sunlight measurements at optical wavelengths. The aerosol number density profile is retrieved for an assumed particle size distribution and composition. This result can be used to derive the extinction at the measured wavelength. However, large systematic error can result from the uncertainty in the assumed size distribution when the result is used to estimate the extinction at other wavelengths. It is shown in this work that the addition of information obtained from the near infrared limb radiance profile at 1530 nm measured by the imaging module of the OSIRIS instrument yields an indication of the aerosol size distribution profile that can be used to improve the fidelity of the retrievals. A comparison of the estimated extinction profile at 1020 nm with coincident occultation measurements demonstrates agreement to within approximately 15% from 12 to 27 km altitude. Ångström, A.: The parameters of atmospheric turbidity, Tellus, 16, 64–75, 1964. Bingen, C., Fussen, D., and Vanhellemont, F.: A global climatology of stratospheric aerosol size distribution parameters derived from SAGE II data over the period 1984–2000: 1. Methodology and climatological observations, J. Geophys. Res., 109, D06201, \doi10.1029/2003JD003518, 2004. Bourassa, A E., Degenstein, D A., Gattinger, R L., and Llewellyn, E J.: Stratospheric aerosol retrieval with OSIRIS limb scatter measurements, J. Geophys. Res., 112, D10 217, \doi10.1029/2006JD008079, 2007. Bourassa, A E., Degenstein, D A., and Llewellyn, E J.: SASKTRAN: A spherical geometry radiative transfer code for efficient estimation of limb scattered sunlight, J. Quant. Spectros. Radiat. Trans., 109, 52–73, 2008. Deshler, T., Hervig, M E., Hofmann, D J., Rosen, J M., and Liley, J B.: Thirty years of in-situ stratospheric aerosol size distribution measurements from Laramie, Wyoming (41 N), using balloon-borne instruments, J. Geophys. Res., 108(D5), 4167, \doi10.1029/2002JD002514, 2003. Grant, W B., Browell, E V., Long, C S., Stowe, L L., Grainger, R G., and Lambert, A.: Use of volcanic aerosols to study the tropical stratospheric reservoir, J. Geophys. Res., 101(D2), 3973–3988, \doi10.1029/95JD03164, 1996. Hansen, J E. and Travis, L D.: Light scattering in planetary atmospheres, Space Sci. Rev., 16, 527–610, 1974. Llewellyn, E J., Lloyd, N D., Degenstein, D A., Gattinger, R L., Petelina, S V., Bourassa, A E., Wiensz, J T., Ivanov, E V., McDade, I C., Solheim, B H., McConnell, J C., Haley, C S., von Savigny, C., Sioris, C E., McLinden, C A., Griffioen, E., Kaminski, J., Evans, W F., Puckrin, E., Strong, K., Wehrle, V., Hum, R H., Kendall, D. J W., Matsushita, J., Murtagh, D P., Brohede, S., Stegman, J., Witt, G., Barnes, G., Payne, W F., Piché, L., Smith, K., Warshaw, G., Deslauniers, D.-L., Marchand, P., Richardson, E H., King, R A., Wevers, I., McCreath, W., Kyrölä, E., Oikarinen, L., Leppelmeier, G W., Auvinen, H., Mégie, G., Hauchecorne, A., Lefèvre, F., de~La~Nöe, J., Ricaud, P., Frisk, U., Sjoberg, F., von Schéele, F., and Nordh, L.: The OSIRIS instrument on the Odin spacecraft, Can. J. Phys., 82, 411–422, 2004. Loughman, R P., Flittner, D E., Herman, B M., Bhartia, P K., Hilsenrath, E., and McPeters, R D.: Description and sensitivity analysis of a limb scattering ozone retrieval algorithm, J. Geophys. Res., 110, D19 301, \doi10.1029/2004JD005429, 2005. McCormick, M P., Hamill, P., Pepin, T J., Chu, W P., Swissler, T J., and McMaster, L R.: Satellite studies of the stratospheric aerosol., B. Am. Meteorol. Soc., 60, 1038–1047, 1979. Russell, P B. and McCormick, M P.: SAGE II aerosol data validation and initial data use: An introduction and overview, J. Geophys. Res., 94, 8335–8338, 1989. Thomason, L W. and Taha, G.: SAGE III aerosol extinction measurements: Initial results, Geophys. Res. Lett., 30(12), 1631, \doi10.1029/2003GL017317, 2003. Trepte, C R. and Hitchman, M H.: Tropical stratospheric circulation deduced from satellite aerosol data, Nature, 355, 626–628, 1992. Wang, P.-H., McCormick, M P., Fuller, W H., Yue, G K., Swissler, T J., and Osborn, M T.: Inference of stratospheric aerosol composition and size distribution from SAGE II satellite measurements, J. Geophys. Res., 94, 8435–8446, 1989.