AbstractThis work presents equatorial ionospheric plasma bubble zonal drift velocity observations and their comparison with model calculations. The bubble zonal velocities were measured using airglow OI630nm all-sky digital images and the model calculations were performed taking into account flux-tube integrated Pedersen conductivity and conductivity weighted neutral zonal winds. The digital images were obtained from an all-sky imaging system operated over the low-latitude station Cachoeira Paulista (Geogr. 22.5S, 45W, dip angle 31.5S) during the period from October 1998 to August 2000. Out of the 138 nights of imager observation, 29 nights with the presence of plasma bubbles are used in this study. These 29 nights correspond to geomagnetically rather quiet days (∑KP<24+) and were grouped according to season. During the early night hours, the calculated zonal drift velocities were found to be larger than the experimental values. The best matching between the calculated and observed zonal velocities were seen to be for a few hours around midnight. The model calculation showed two humps around 20 LT and 24 LT that were not present in the data. Average decelerations obtained from linear regression between 20LT and 24LT were found to be: (a) Spring 1998, −8.61ms−1h−1; (b) Summer 1999, −0.59ms−1h−1; (c) Spring 1999, −11.72ms−1h−1; and (d) Summer 2000, −8.59ms−1h−1. Notice that Summer and Winter here correspond to southern hemisphere Summer and Winter, not northern hemisphere.
Theoretical and experimental zonal drift velocities of the ionospheric plasma bubbles over the Brazilian region
Advances in Space Research ; 38 , 11 ; 2610-2614
2006-05-19
5 pages
Article (Journal)
Electronic Resource
English
British Library Conference Proceedings | 1999
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