Studies on the variability of mean winds in the mesosphere and lower thermosphere region (MLT) over Kolhapur (16.8oN, 74.2oE)

Authors

  • G.P. Naniwadekar Sou.S.M.Lohia Junior College, Kolhapur, India/ Physics Department, Shivaji University, Kolhapur, India
  • S. Gurubaran Indian Institute of Geomagnetism, Navi Mumbai, India
  • A.P. Jadhav Indian Institute of Geomagnetism, Navi Mumbai, India
  • R.N. Ghodpage M.F. Radar Facility, Indian Institute of Geomagnetism, Shivaji University Campus, Kolhapur, India
  • P.T. Patil M.F. Radar Facility, Indian Institute of Geomagnetism, Shivaji University Campus, Kolhapur, India
  • D.S. Burud Sh. M. M. Patel Institute of Sciences and Research, KadiSarvaVishwavidyalaya, Gandhinagar, India

DOI:

https://doi.org/10.58825/jog.2023.17.1.78

Keywords:

Wind profiles, MF (medium frequency) radar, low latitude, MLT region, Annual Oscillation, Semi-annual Oscillation

Abstract

We present the study of mesospheric winds in the 78–98 km height range using observations by a partial reflection radar station (MF–radar) situated at Kolhapur (16.8° N, 74.2° E), India. The sequential wind profiles over the period of 2014–2019 obtained from this radar operated at 1.98 MHz are used for this study. To delineate the behaviour of the winds in the mesosphere and lower thermosphere (MLT) region, we use wind data providing horizontal wind velocities averaged for an hour. Details of the seasonal, annual, and inter-annual variations and also the climatology of mean motion in zonal (East-West) and meridional (North-South) components in the MLT region over the aforementioned period are presented. The zonal wind below 90 km has been observed with eastward flow for the period of solstices and westward flow at equinoxes, showing strong semi-annual oscillations (SAO). While above 90 km, annual oscillations (AO) are seen to be dominant. Annual oscillations (AO) are observed in the mean meridional wind, with poleward motion during winter and equatorward motion during the remaining seasons. At higher altitudes (above 92 km), the poleward motion weakens and the equatorward wind flow becomes strong.

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Published

2023-04-28

How to Cite

Naniwadekar, G., Gurubaran, S., Jadhav, A., Ghodpage, R., Patil, P., & Burud, D. (2023). Studies on the variability of mean winds in the mesosphere and lower thermosphere region (MLT) over Kolhapur (16.8oN, 74.2oE). Journal of Geomatics, 17(1), 87–94. https://doi.org/10.58825/jog.2023.17.1.78

Issue

Vol. 17 No. 1 (2023): Journal of Geomatics

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