Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1
Data from the Jicamarca digisonde and the ROCSAT-1 satellite are employed to study the equatorial ionosphere on the west side of South America during April 1999-March 2000 for the concurrent bottomside spread F (BSSF) and plasma bubble events. This study, using digisonde and ROCSAT-1 concurrently...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2005-12-01
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| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/23/3473/2005/angeo-23-3473-2005.pdf |
| _version_ | 1828543010981281792 |
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| author | C.-C. Lee S.-Y. Su B. W. Reinisch |
| author_facet | C.-C. Lee S.-Y. Su B. W. Reinisch |
| author_sort | C.-C. Lee |
| collection | DOAJ |
| description | Data from the Jicamarca digisonde and the ROCSAT-1 satellite are employed to
study the equatorial ionosphere on the west side of South America during
April 1999-March 2000 for the concurrent bottomside spread F (BSSF) and
plasma bubble events. This study, using digisonde and ROCSAT-1 concurrently,
is the first attempt to investigate the equatorial spread F. Results show
that BSSF and plasma bubble observations appear frequently respectively in the summer (January,
February, November, and December) and in the equinoctial (March, April,
September, and October) months, respectively, but are both rarely observed in the winter
(May-August) months. The upward drift velocity during the concurrent BSSF
and bubble observations has been determined to study the driving mechanism.
This analysis shows that large vertical drift velocities favor BSSF and
bubble formations in the equinoctial and summer months. Conversely, the
smaller upward velocities during the winter months cause fewer BSSF and
bubble occurrences. For the geomagnetic effect, the BSSF/bubble occurrence
decreases with an increasing <i>K<sub>p</sub></i> value in the equinoctial months, but no such
correlation is found for the summer and winter months. Moreover, the
anti-correlations between <i>K<sub>p</sub></i> and d<i>h'F</i>/dt are apparent in the equinoctial months,
but not in the summer and winter months. These results indicate that in the
equinoctial months the BSSF/bubble generations and the pre-reversal drift
velocity can be suppressed by geomagnetic activity, because the disturbance
dynamo effects could have decreased the eastward electric field near sunset.
However, BSSF and bubble occurrences may not be suppressed by the
geomagnetic activity in the summer and winter months. |
| first_indexed | 2024-12-12T02:06:05Z |
| format | Article |
| id | doaj.art-66953356afa148d0a89047542f2ec099 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-12-12T02:06:05Z |
| publishDate | 2005-12-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-66953356afa148d0a89047542f2ec0992022-12-22T00:42:02ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05762005-12-01233473348010.5194/angeo-23-3473-2005Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1C.-C. Lee0S.-Y. Su1B. W. Reinisch2General Education Center, Ching-Yun University, Jhongli City, Taoyuan County, TaiwanInstitute of Space Science and Center for Space and Remote Sensing Research, National Central University, Jhongli City, Taoyuan County, TaiwanCenter for Atmospheric Research, University of Massachusetts Lowell, Massachusetts, USAData from the Jicamarca digisonde and the ROCSAT-1 satellite are employed to study the equatorial ionosphere on the west side of South America during April 1999-March 2000 for the concurrent bottomside spread F (BSSF) and plasma bubble events. This study, using digisonde and ROCSAT-1 concurrently, is the first attempt to investigate the equatorial spread F. Results show that BSSF and plasma bubble observations appear frequently respectively in the summer (January, February, November, and December) and in the equinoctial (March, April, September, and October) months, respectively, but are both rarely observed in the winter (May-August) months. The upward drift velocity during the concurrent BSSF and bubble observations has been determined to study the driving mechanism. This analysis shows that large vertical drift velocities favor BSSF and bubble formations in the equinoctial and summer months. Conversely, the smaller upward velocities during the winter months cause fewer BSSF and bubble occurrences. For the geomagnetic effect, the BSSF/bubble occurrence decreases with an increasing <i>K<sub>p</sub></i> value in the equinoctial months, but no such correlation is found for the summer and winter months. Moreover, the anti-correlations between <i>K<sub>p</sub></i> and d<i>h'F</i>/dt are apparent in the equinoctial months, but not in the summer and winter months. These results indicate that in the equinoctial months the BSSF/bubble generations and the pre-reversal drift velocity can be suppressed by geomagnetic activity, because the disturbance dynamo effects could have decreased the eastward electric field near sunset. However, BSSF and bubble occurrences may not be suppressed by the geomagnetic activity in the summer and winter months.https://www.ann-geophys.net/23/3473/2005/angeo-23-3473-2005.pdf |
| spellingShingle | C.-C. Lee S.-Y. Su B. W. Reinisch Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1 Annales Geophysicae |
| title | Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1 |
| title_full | Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1 |
| title_fullStr | Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1 |
| title_full_unstemmed | Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1 |
| title_short | Concurrent study of bottomside spread F and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and ROCSAT-1 |
| title_sort | concurrent study of bottomside spread f and plasma bubble events in the equatorial ionosphere during solar maximum using digisonde and rocsat 1 |
| url | https://www.ann-geophys.net/23/3473/2005/angeo-23-3473-2005.pdf |
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