Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time Variations
Abstract This study presents a statistical analysis of the occurrence rate of midlatitude nighttime medium scale traveling ionospheric disturbances (MSTIDs) that were detected in Swarm plasma density measurements from 2014 to 2023. Monthly and local time variations of MSTID occurrence rates are comp...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2025-07-01
|
| Series: | Space Weather |
| Online Access: | https://doi.org/10.1029/2024SW004254 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849729272240930816 |
|---|---|
| author | Zama T. Katamzi‐Joseph John Bosco Habarulema Yuichi Otsuka Tshimangadzo M. Matamba Amoré E. Nel |
| author_facet | Zama T. Katamzi‐Joseph John Bosco Habarulema Yuichi Otsuka Tshimangadzo M. Matamba Amoré E. Nel |
| author_sort | Zama T. Katamzi‐Joseph |
| collection | DOAJ |
| description | Abstract This study presents a statistical analysis of the occurrence rate of midlatitude nighttime medium scale traveling ionospheric disturbances (MSTIDs) that were detected in Swarm plasma density measurements from 2014 to 2023. Monthly and local time variations of MSTID occurrence rates are compared in four longitude sectors: America, Africa, Asia, and Pacific. The spatial distribution showed a longitudinal variation as the MSTIDs were abundant in the Pacific region and scarce in the African sector. While the MSTIDs had occurrence peaks during both solstices, the winter solstice peak dominated in all longitude sectors, representing a seasonal asymmetry. The local time variation of the MSTIDs revealed they occur predominantly during the post‐midnight hours in all longitude sectors. However, post‐sunset MSTIDs observations were enhanced over the Asian and Pacific sectors during the solstices. The longitudinal variation in the occurrence of MSTIDs is probably linked to the E–F coupling as it matched that of the nighttime sporadic E variation obtained from ionosonde measurements. While the winter dominance of MSTIDs matches that of gravity wave activity, the semiannual seasonal variation may be explained by interhemispheric E–F coupling. This indicates that gravity waves probably play a major role in seeding the MSTIDs observed in this study. Theoretical assessments of the longitudinal variations of MSTID driving mechanisms are needed to better understand the seasonal asymmetry and how it is affected by solar activity. |
| format | Article |
| id | doaj-art-cef756ca6d8a4ac09635dddea411d8aa |
| institution | DOAJ |
| issn | 1542-7390 |
| language | English |
| publishDate | 2025-07-01 |
| publisher | Wiley |
| record_format | Article |
| series | Space Weather |
| spelling | doaj-art-cef756ca6d8a4ac09635dddea411d8aa2025-08-20T03:09:16ZengWileySpace Weather1542-73902025-07-01237n/an/a10.1029/2024SW004254Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time VariationsZama T. Katamzi‐Joseph0John Bosco Habarulema1Yuichi Otsuka2Tshimangadzo M. Matamba3Amoré E. Nel4SANSA Hermanus South AfricaSANSA Hermanus South AfricaInstitute for Space‐Earth Environmental Research Nagoya University Nagoya JapanSANSA Hermanus South AfricaSANSA Hermanus South AfricaAbstract This study presents a statistical analysis of the occurrence rate of midlatitude nighttime medium scale traveling ionospheric disturbances (MSTIDs) that were detected in Swarm plasma density measurements from 2014 to 2023. Monthly and local time variations of MSTID occurrence rates are compared in four longitude sectors: America, Africa, Asia, and Pacific. The spatial distribution showed a longitudinal variation as the MSTIDs were abundant in the Pacific region and scarce in the African sector. While the MSTIDs had occurrence peaks during both solstices, the winter solstice peak dominated in all longitude sectors, representing a seasonal asymmetry. The local time variation of the MSTIDs revealed they occur predominantly during the post‐midnight hours in all longitude sectors. However, post‐sunset MSTIDs observations were enhanced over the Asian and Pacific sectors during the solstices. The longitudinal variation in the occurrence of MSTIDs is probably linked to the E–F coupling as it matched that of the nighttime sporadic E variation obtained from ionosonde measurements. While the winter dominance of MSTIDs matches that of gravity wave activity, the semiannual seasonal variation may be explained by interhemispheric E–F coupling. This indicates that gravity waves probably play a major role in seeding the MSTIDs observed in this study. Theoretical assessments of the longitudinal variations of MSTID driving mechanisms are needed to better understand the seasonal asymmetry and how it is affected by solar activity.https://doi.org/10.1029/2024SW004254 |
| spellingShingle | Zama T. Katamzi‐Joseph John Bosco Habarulema Yuichi Otsuka Tshimangadzo M. Matamba Amoré E. Nel Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time Variations Space Weather |
| title | Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time Variations |
| title_full | Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time Variations |
| title_fullStr | Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time Variations |
| title_full_unstemmed | Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time Variations |
| title_short | Characteristics of Nighttime Medium‐Scale Traveling Ionospheric Disturbances: Longitudinal Comparison of Their Seasonal and Local Time Variations |
| title_sort | characteristics of nighttime medium scale traveling ionospheric disturbances longitudinal comparison of their seasonal and local time variations |
| url | https://doi.org/10.1029/2024SW004254 |
| work_keys_str_mv | AT zamatkatamzijoseph characteristicsofnighttimemediumscaletravelingionosphericdisturbanceslongitudinalcomparisonoftheirseasonalandlocaltimevariations AT johnboscohabarulema characteristicsofnighttimemediumscaletravelingionosphericdisturbanceslongitudinalcomparisonoftheirseasonalandlocaltimevariations AT yuichiotsuka characteristicsofnighttimemediumscaletravelingionosphericdisturbanceslongitudinalcomparisonoftheirseasonalandlocaltimevariations AT tshimangadzommatamba characteristicsofnighttimemediumscaletravelingionosphericdisturbanceslongitudinalcomparisonoftheirseasonalandlocaltimevariations AT amoreenel characteristicsofnighttimemediumscaletravelingionosphericdisturbanceslongitudinalcomparisonoftheirseasonalandlocaltimevariations |