Long term variations in equatorial strato-and mesospheric temperatures
M-100 Rocketsonde temperature data of Thumba in the 30 to 80 km height range for the period 1971-74 are analysed for studying the long term variations at 5 km altitude intervals. It is observed that the amplitude of the semi-annual oscillation dominates over that of the annual oscillation in the stratosphere and close to mesopause. However, the amplitude of the annual oscillation shows a quasi-peak around 70 Km altitude. The phase of the semi-annual oscillation is observed to propagate downward from mesopause while the phase of the annual component propagates on to either side from the stratopause. From a vertical time-section prepared after filtering out periods greater than 3 months wave disturbances of a few weeks period with vertical scale sizes greater than 20 Km sides are observed. A power spectral analysis shows a dominant period well, above the noise level at 52.5 days above the stratopause. Secondary peaks of lesser significance are observed with periods between 17.5 and 30.0 days.
How to Cite
Copyright (c) 2021 MAUSAM
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
All articles published by MAUSAM are licensed under the Creative Commons Attribution 4.0 International License. This permits anyone.
Anyone is free:
- To Share - to copy, distribute and transmit the work
- To Remix - to adapt the work.
Under the following conditions:
- Share - copy and redistribute the material in any medium or format
- Adapt - remix, transform, and build upon the material for any purpose, even