Skip to main content
Log in

Continuous excitation of planetary free oscillations by atmospheric disturbances

  • Letter
  • Published:

From Nature

View current issue Submit your manuscript

Abstract

Seismology provides a powerful tool for probing planetary interiors1,2, but it has been considered inapplicable to tectonically inactive planets where earthquakes are absent. Here, however, we show that the atmospheres of solid planets are capable of exerting dynamic pressure on their surfaces, thereby exciting free oscillations with amplitudes large enough to be detected by modern broad-band seismographs. Order-of-magnitude estimates of these forces give similar amplitudes of a few nanogals for the Earth, Venus and Mars despite widely varying atmospheric and ambient conditions. The amplitudes are also predicted to have a weak frequency dependence. Our analysis of seismograms, recorded continuously from 1992 to 1993 at 13 globally distributed stations, shows strong evidence for continuously excited fundamental-mode free oscillations on the Earth. This result, together with other recent studies3,4,5, is consistent with our estimate of atmospheric forcing and we therefore propose that it may be possible to detect atmospheric excitation of free oscillations on Venus and Mars as well.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Figure 1: Earth's free oscillations on the quietest days.
Figure 2: Continuously excited free oscillations were observed globally.

Similar content being viewed by others

References

  1. Gilbert, F. & Dziewonski, A. M. An application of normal mode theory to the retrieval of structural parameters and source mechanisms from seismic spectra. Phil. Trans. R. Soc. Lond. A 278, 187–269 (1975).

    Article  ADS  Google Scholar 

  2. Dziewonski, A. M. & Anderson, D. L. Preliminary reference Earth model. Phys. Earth Planet. Inter. 25, 297–356 (1981).

    Article  ADS  Google Scholar 

  3. Nawa, K. et al. Incessant excitation of the Earth's free oscillations. Earth Planets Space 50, 3–8 (1998).

    Article  ADS  Google Scholar 

  4. Suda, N., Nawa, K. & Fukao, Y. Earth's background free oscillations. Science 279, 2089–2091 (1998).

    Article  ADS  CAS  Google Scholar 

  5. Tanimoto, T., Um, J., Nishida, K. & Kobayashi, N. Earth's continuous oscillations observed on seismically quiet days. Geophys. Res. Lett. 25, 1553–1556 (1998).

    Article  ADS  Google Scholar 

  6. Goldreich, P. & Kumar, P. The interaction of acoustic radiation with turbulence. Astrophys. J. 326, 462–478 (1988).

    Article  ADS  Google Scholar 

  7. Sagan, C. Structure of the lower atmosphere of Venus. Icarus 1, 151–169 (1962).

    Article  ADS  Google Scholar 

  8. Howard, J. N., Burch, D. E. & Williams, D. Infrared transmission of synthetic atmospheres. Parts I–V. J. Opt. Soc. Am. 46, 186–190, 237–241, 242–245, 334–338, 452–455 (1956).

    Article  ADS  CAS  Google Scholar 

  9. Gilbert, F. Excitation of the normal modes of the Earth by earthquake sources. Geophys. J. R. Astron. Soc. 22, 223–226 (1970).

    Article  ADS  Google Scholar 

  10. Osaki, Y. in Progress of Seismology of the Sun and Stars (eds Osaki, Y. & Shibahashi, H.) 75–86 (Lecture Notes in Physics Vol. 367, Springer, Berlin, (1989)).

    Google Scholar 

  11. Wielandt, E. & Streckeisen, G. The leafspring seismometer: design and performance. Bull. Seismol. Soc. Am. 72, 2349–2367 (1982).

    Google Scholar 

  12. Kamal & Mansinha, L. Atest of the superconducting gravimeter as a long-period seismometer. Phys. Earth Planet. Inter. 71, 52–60 (1992).

    Article  ADS  Google Scholar 

  13. Smith, S. W. IRIS: A program for the next decade. Eos 67, 213–219 (1986).

    Article  ADS  Google Scholar 

  14. Dziewonski, A. M. & Woodhouse, J. H. An experiment in the systematic study of global seismicity: centroid-moment tensor solutions for 201 moderate and large earthquakes of 1981. J. Geophys. Res. 88, 3247–3271 (1983).

    Article  ADS  Google Scholar 

  15. Bullen, K. E. & Bolt, B. A. An Introduction to the Theory of Seismology 4th edn (Cambridge Univ. Press, (1985)).

    MATH  Google Scholar 

  16. Beroza, G. & Jordan, T. Searching for slow and silent earthquakes using free oscillations. J. Geophys. Res. 95, 2485–2510 (1990).

    Article  ADS  Google Scholar 

  17. Turcotte, D. L. & Schubert, G. Geodynamics Applications of Continuum Physics to Geological Problems (Wiley, New York, (1982)).

    Google Scholar 

Download references

Acknowledgements

We thank R. Geller, S. Ida, M. Fujimoto and Y. Fukao for comments on this manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Naoki Kobayashi.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kobayashi, N., Nishida, K. Continuous excitation of planetary free oscillations by atmospheric disturbances. Nature 395, 357–360 (1998). https://doi.org/10.1038/26427

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/26427

  • Springer Nature Limited

This article is cited by

Navigation