Advertisement

Validation of GOMOS/Envisat High-Resolution Temperature Profiles (HRTP) Using Spectral Analysis

  • V.F. SofievaEmail author
  • J. Vira
  • F. Dalaudier
  • A. Hauchecorne
  • the Gomos Team
Chapter

Abstract

The GOMOS (Global Ozone Monitoring by Occultation of Stars) instrument on board the Envisat satellite is equipped with two fast photometers operating at 1 kHz sampling frequency in blue and red wavelengths. The bi-chromatic scintillations recorded by the photometers allow the determination of refractive angle, which is proportional to the time delay between the photometer signals. The high resolution density and temperature profiles can be reconstructed (with a vertical resolution of about 200 m) from these data in the altitude range ∼15–35 km. The validation of small-scale fluctuations in HRTP requires a very close collocation in time and space with high-quality data having comparable or better vertical resolution. Comparing spatial spectra of temperature profile fluctuations requires less strict collocation criteria. In this paper, we compared vertical wavenumber spectra of temperature fluctuations in HRTP and in collocated radiosonde data. We found that the vertical wavenumber spectra of HRTP and radiosonde temperature fluctuations are very similar in case of vertical occultations of bright stars. In case of oblique occultations or of dim stars, the HRTP fluctuations often have a larger spectral magnitude, despite of several good agreements. The spectral analysis has confirmed that the actual resolution of HRTP is 150–200 m.

Keywords

Vertical Resolution Horizontal Wind Radio Occultation Internal Gravity Wave Bright Star 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

This work has been performed within the scope of the ESA funded project “Algorithms for the estimation of high resolution temperature and density profiles from GOMOS measurements” (Contract number 17895/04/I-LG). The authors thank ESA and the GOMOS team for the GOMOS data. The authors greatly appreciate the use of correlative data from the ENVISAT Cal/Val database at NILU, and thank the principal investigators of the radiosondes and SHADOZ sondes. The work of V.F. Sofieva was supported by the Academy of Finland (postdoctoral researcher project).

References

  1. Bertaux JL, Hauchecorne A, Dalaudier F, Cot C, Kyrola E, Fussen D, Tamminen J, Leppelmeier GW, Sofieva V, Hassinen S, Fanton d'Andon O, Barrot G, Mangin A, Theodore B, Guirlet M, Korablev O, Snoeij P, Koopman R, Fraisse R (2004) First results on GOMOS/Envisat. Adv Space Res 33:1029–1035, doi:10.1016/j.asr.2003.09.037Google Scholar
  2. Dalaudier F, Sofieva V, Hauchecorne A, Kyrölä E, Blanot L, Guirlet M, Retscher C, Zehner C (2006) High-resolution density and temperature profiling in the stratosphere using bi-chromatic scintillation measurements by GOMOS. Proceedings of the First Atmospheric Science Conference, European Space Agency, ISBN 92-9092-939-1-ISSN 1609-042XGoogle Scholar
  3. Eckermann SD (1995) Effect of background winds on vertical wavenumber spectra of atmospheric gravity waves. J Geophys Res 100(D7):14097–14112CrossRefGoogle Scholar
  4. Fritts DC, Alexander MJ (2003) Gravity wave dynamics and effects in the middle atmosphere. Rev Geophys 41(1):1003, doi:10.1029/2001RG00106Google Scholar
  5. Gardner C, Gardner N (1993) Measurement distortion in aircraft, space shuttle, and balloon observations of atmospheric density and temperature perturbation spectra. J Geophys Res 98(D1):1023–1033CrossRefGoogle Scholar
  6. Kyrölä E, Tamminen J, Leppelmeier GW, Sofieva V, Hassinen S, Bertaux JL, Hauchecorne A, Dalaudier F, Cot C, Korablev O, Fanton d’Andon O, Barrot G, Mangin A, Theodore B, Guirlet M, Etanchaud F, Snoeij P, Koopman R, Saavedra L, Fraisse R, Fussen D, Vanhellemont F (2004) GOMOS on Envisat: An overview. Adv Space Res 33:1020–1028, doi:10.1016/S0273-1177(03)00590-8Google Scholar
  7. Smith SA, Fritts DC, VanZandt TE (1987) Evidence of a saturation spectrum of atmospheric gravity waves. J Atmos Sci 44(10):1404–1410CrossRefGoogle Scholar
  8. Sofieva VF, Dalaudier F, Kivi R, Kyrö E (2008) On the variability of temperature profiles in the stratosphere: Implications for validation. Geophys Res Lett 35(L23808), doi:10.1029/ 2008GL035539Google Scholar
  9. Thompson AM, Witte JC, McPeters RD, Oltmans SJ, Schmidlin FJ, Logan JA, Fujiwara M, Kirchhoff VWJH, Posny F, Coetzee GJR, Hoegger B, Kawakami S, Ogawa T, Johnson BJ, Vömel H, Labow G (2001) Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998–2000 tropical ozone climatology 1. Comparison with Total Ozone Mapping Spectrometer (TOMS) and ground-based measurements. J Geophys Res 108(D2):8238, doi:10.1029/2001JD000967Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • V.F. Sofieva
    • 1
    Email author
  • J. Vira
    • 1
  • F. Dalaudier
    • 2
  • A. Hauchecorne
    • 2
  • the Gomos Team
    • 2
  1. 1.Finnish Meteorological InstituteEarth ObservationHelsinkiFinland
  2. 2.Service d´Aeronomie du CNRSVerrieres–le–Buisson CEDEXFrance

Personalised recommendations