Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 1.621 IF 1.621
  • IF 5-year value: 1.614 IF 5-year
    1.614
  • CiteScore value: 1.61 CiteScore
    1.61
  • SNIP value: 0.900 SNIP 0.900
  • IPP value: 1.58 IPP 1.58
  • SJR value: 0.910 SJR 0.910
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 80 Scimago H
    index 80
  • h5-index value: 24 h5-index 24
Volume 19, issue 8
Ann. Geophys., 19, 1019-1025, 2001
https://doi.org/10.5194/angeo-19-1019-2001
© Author(s) 2001. This work is distributed under
the Creative Commons Attribution 3.0 License.

Special issue: MST

Ann. Geophys., 19, 1019-1025, 2001
https://doi.org/10.5194/angeo-19-1019-2001
© Author(s) 2001. This work is distributed under
the Creative Commons Attribution 3.0 License.

  31 Aug 2001

31 Aug 2001

Turbulence characteristics in the tropical mesosphere as obtained by MST radar at Gadanki (13.5° N, 79.2° E)

M. N. Sasi and L. Vijayan M. N. Sasi and L. Vijayan
  • Space Physics Laboratory, Vikram Sarabhai Space Centre, Trivandrum 695022, India

Abstract. Turbulent kinetic energy dissipation rates (ε) and eddy diffusion coefficients (Kz) in the tropical mesosphere over Gadanki (13.5° N, 79.2° E), estimated from Doppler widths of MST radar echoes (vertical beam), observed over a 3-year period, show a seasonal variation with a dominant summer maximum. The observed seasonal variation of ε and Kz in the mesosphere is only partially consistent with that of gravity wave activity inferred from mesospheric winds and temperatures measured by rockets for a period of 9 years at Trivandrum (8.5° N, 77° E) (which shows two equinox and one summer maxima) lying close to Gadanki. The summer maximum of mesospheric ε and Kz values appears to be related to the enhanced gravity wave activity over the low-latitude Indian subcontinent during the southwest monsoon period (June – September). Both ε and Kz in the mesosphere over Gadanki show an increase with an increase in height during all seasons. The absolute values of observed ε and Kz in the mesosphere (above ~80 km) does not show significant differences from those reported for high latitudes. Comparison of observed Kz values during the winter above Gadanki with those over Arecibo (18.5° N, 66° W) shows that they are not significantly different from each other above the ~80 km altitude.

Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; tropical meteorology; wave and tides)

Publications Copernicus
Special issue
MST
Download
Citation
Share