Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 8 11 2008 10.5194/acp-8-2965-2008 http://www.atmos-chem-phys.net/8/2965/2008/ http://www.atmos-chem-phys.net/8/2965/2008/acp-8-2965-2008.html http://www.atmos-chem-phys.net/8/2965/2008/acp-8-2965-2008.pdf 2965 2973 2008-06-12 Reconstruction of the solar spectral UV irradiance for nowcasting of the middle atmosphere state on the basis of LYRA measurements T. Egorova E. Rozanov e.rozanov@pmodwrc.ch J.-F. Hochedez W. Schmutz Physikalisch-Meteorologisches Observatorium Davos and World Radiation Center, Dorfstrasse 33, 7260 Davos Dorf, Switzerland Institute for Atmospheric and Climate Science, ETH Zürich, Universitätsstr. 16, 8092 Zürich, Switzerland Royal Observatory of Belgium, Circular Avenue 3, 1180 Brussels, Belgium The LYRA instrument onboard ESA PROBA2 satellite will provide 6-hourly solar irradiance at the Lyman-alpha (121.6 nm) and the Herzberg continuum (~200–220 nm wavelength range). Because the nowcasting of the neutral and ionic state of the middle atmosphere requires the solar irradiance for the wide spectral range (120–680 nm) we have developed the statistical tool for the reconstruction of the full spectrum from the LYRA measurements. The accuracy of the reconstructed irradiance has been evaluated with 1-D transient radiative-convective model with neutral and ion chemistry using the daily solar spectral irradiance measured with SUSIM and SOLSTICE instruments onboard UARS satellite. We compared the results of transient 1-year long model simulations for 2000 driven by the observed and reconstructed solar irradiance and showed that the reconstruction of the full spectrum using linear regression equation based on the solar irradiance in two LYRA channels can be successfully used for nowcasting of the middle atmosphere. We have also identified conditions when the proposed approach does not yield spectral reconstruction with sufficient accuracy. Brasseur, G. and Solomon, S.: Aeronomy of the middle atmosphere: Chemistry and physics of the stratosphere and mesosphere, Third edition, Springer, Dordrecht, the Netherlands, 646 pp., 2005. Dudok de Wit, T., Lilensten, J., Aboudarham, J., Amblard, P.-O., and Kretzschmar, M.: Retrieving the solar EUV spectrum from a reduced set of spectral lines, Ann. Geophys., 23, 3055–3069, 2005. Egorova, T. A., Karol, I. L. and Rozanov, E. V.: The influence of ozone content loss in the lower stratosphere on the radiative balance of the troposphere, Physics of atmosphere and ocean (Russian Academy of Sciences), 33, N4, 492–499, 1997. Floyd, L. E., Reiser, P. A., Crane, P. C., Herring, L. C., Prinz, D. K., Brueckner, G. E.: Solar cycle 22 UV spectral irradiance variability: current measurements by SUSIM UARS, Solar Phys., 177, 79–87, 1998. Fomichev, V. I., Blanchet, J.-P., and Tuner, D. S.: Matrix parameterization of the 15 micro CO2 band cooling in the middle and upper atmosphere for variable CO2 concentration, J. Geophys. Res., 103, 11 505–11 528, 1998. Frolkis, V. A. and Rozanov, E. V.: Radiation code for climate and general circulation models. IRS'92: Current problems in atmospheric radiation, Tallin, Estonia, 3–8 August, 176–179, 1992. Jansen, F, Pirjola, R., and Favre, R.: Space weather: Hazard to the Earth?, Swiss Re Publishing, Zurich, 39 pp., 2000. Heaps, M. G.: Parameterization of the cosmic ray ion-pair production rate above 18 km, Planet Space Sci., 26, 513–517, 1978. Hochedez, J.-F., Schmutz, W., Stockman, Y., et al.: LYRA: the Solar UV radiometer aboard the ESA Proba-2, LYRA, a solar UV radiometer on Proba2, Adv. Space Res., 37, 303–312, 2006. Kazil, J.: The University of Bern Atmospheric Ion Model: Time-Dependent Ion Modeling in the Stratosphere, Mesosphere and Lower Thermosphere, PhD Thesis, University of Bern, Switzertland, 2002. Koop, E.: Electron and ion dencities, in: The Upper Atmosphere, edited by: W. Dieminger, G. K., Hartman, R. leitinger, Springer, 1996. Krivova, N. A, Solanki, S. K., and Floyd, L.: Reconstruction of solar UV irradiance in cycle 23, Astronomy and Astrophysics, 452, 631–639, 2006. Rottman, G. J., Woods, T. N., and Sparn, T. P.: Solar stellar irradiance comparison experiment I: 1 instrument design and operation, J. Geophys. Res. 98, 10 667–10 677, 1993. Rottman, G., Woods, T., and McClintock, W.: SORCE solar UV irradiance results, Adv. Space Res., 37, 2, 201–208, 2006. Rozanov, E. V., Zubov, V. A., Schlesinger, M. E., Yang, F., and Andronova N. G.: The UIUC 3-D Stratospheric Chemical Transport Model: Description and Evaluation of the simulated Source Gases and Ozone, J. Geophys. Res., 104, 11 755–11 781, 1999. Rozanov, E., Egorova T., Fröhlich, C., Haberreiter, M., Peter, T., and Schmutz, W.: Estimation of the Ozone and Temperature Sensitivity to the Variation of Spectral Solar Flux, in: SOHO 11 Symposium From Solar Min to Max: Half a Solar Cycle with SOHO, edited by: A. Wilson, ESA SP-508, ESA Publications Division, Noordwijk, The Netherlands, 181–184, 2002. Rozanov, E., Egorova, T., and Schmutz, W.: Response of the Earth's Atmosphere to the Solar Irradiance Variability, in: Climate Variability and Extremes during the Past 100 Years, edited by: Brönnimann, S., Luterbacher, J., Ewen, T., Diaz, H. F., Stolarski, R. S., and Neu, U., Advances in Global Change Research, 33, 317–331, Springer, 2008. Sander, S. P., Friedl, R., Golden, D., et al.: Chemical kinetics and photochemical data for use in atmospheric studies: Evaluation number 14, Tech. Rep. JPL Publ. 02-25, Jet Propulsion Laboratory, 2003. Thuillier, G., Dewitte, S., Schmutz, W., and the Picard Team: Simultaneous measurement of the total solar irradiance and solar diameter by the PICARD mission, Adv. Space Res., 38, 1792–1806, 2006. Unruh, Y., Krivova, N., Solanki, S., Harder, J., and Kopp, G.: Spectral irradiance variations: Comparison between observations and the SATIRE model on solar rotation time scales, Astronomy and Astrophysics, accepted, 2008. Wilkinson, D. C.: National Oceanic and Atmospheric Administration's spacecraft anomaly data base and examples of solar activity affecting spacecraft, J. Spacecraft and Rockets, 31, March–April, 1994. Woods, T. N., Prinz, D. K., Rottman, G. J., et al.: Validation of the UARS solar ultraviolet irradiances: Comparison with ATLAS 1 and 2 measurements, J. Geophys. Res., 101, 9541–9569, 1996.