Abstract
The magnetic field records of the magnetometer networks in the American, East Asian-Australian, and European-African sectors were employed in this present work. We used them to investigate equatorial electrojet (EEJ), counter electrojet (CEJ), tidal variability in EEJ strength and ionospheric current during the 2005/2006 and 2008/2009 sudden stratospheric warming (SSW) events. In addition to the well-investigated tidal variability in EEJ strength over the American and East Asian sectors, we investigated that of the African sector for the first time. Interestingly, the tidal components in EEJ strength during both SSW events clearly exhibit marked longitudinal differences with high, moderate, and low amplitudes in the American, East Asian, and African sectors, respectively. An exception found around day 71 in the African sector after the 2008/2009 SSW event had higher solar diurnal tidal component as compared to that of the Asian sector. Over the American sector, solar and lunar semidiurnal tides were strongly associated with CEJ current during both SSW events, whereas at the African and East Asian sectors such variabilities are not evident. A solar diurnal tidal component was strongly related to a reduction in the EEJ strength over the East Asian sector. In addition, a prolonged period of CEJ occurrence that begins during the SSW precondition and ends when the SSW was evolving characterized the African sector during both SSW events. There is a steady shift in phase at later hours when both SSW events are evolving.
| Original language | English |
|---|---|
| Pages (from-to) | 6156-6172 |
| Number of pages | 17 |
| Journal | Journal of Geophysical Research: Space Physics |
| Volume | 124 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - Jan 1 2019 |
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All Science Journal Classification (ASJC) codes
- Geophysics
- Forestry
- Oceanography
- Aquatic Science
- Ecology
- Water Science and Technology
- Soil Science
- Geochemistry and Petrology
- Earth-Surface Processes
- Atmospheric Science
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science
- Palaeontology
Cite this
Investigation on the Variability of the Geomagnetic Daily Current During Sudden Stratospheric Warmings. / Owolabi, Charles; Lei, Jiuhou; Bolaji, O. S.; Jimoh, Oluwaseyi; Ruan, Haibing; Li, Na; Niu, Xiaojuan; Yoshikawa, Akimasa.
In: Journal of Geophysical Research: Space Physics, Vol. 124, No. 7, 01.01.2019, p. 6156-6172.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Investigation on the Variability of the Geomagnetic Daily Current During Sudden Stratospheric Warmings
AU - Owolabi, Charles
AU - Lei, Jiuhou
AU - Bolaji, O. S.
AU - Jimoh, Oluwaseyi
AU - Ruan, Haibing
AU - Li, Na
AU - Niu, Xiaojuan
AU - Yoshikawa, Akimasa
PY - 2019/1/1
Y1 - 2019/1/1
N2 - The magnetic field records of the magnetometer networks in the American, East Asian-Australian, and European-African sectors were employed in this present work. We used them to investigate equatorial electrojet (EEJ), counter electrojet (CEJ), tidal variability in EEJ strength and ionospheric current during the 2005/2006 and 2008/2009 sudden stratospheric warming (SSW) events. In addition to the well-investigated tidal variability in EEJ strength over the American and East Asian sectors, we investigated that of the African sector for the first time. Interestingly, the tidal components in EEJ strength during both SSW events clearly exhibit marked longitudinal differences with high, moderate, and low amplitudes in the American, East Asian, and African sectors, respectively. An exception found around day 71 in the African sector after the 2008/2009 SSW event had higher solar diurnal tidal component as compared to that of the Asian sector. Over the American sector, solar and lunar semidiurnal tides were strongly associated with CEJ current during both SSW events, whereas at the African and East Asian sectors such variabilities are not evident. A solar diurnal tidal component was strongly related to a reduction in the EEJ strength over the East Asian sector. In addition, a prolonged period of CEJ occurrence that begins during the SSW precondition and ends when the SSW was evolving characterized the African sector during both SSW events. There is a steady shift in phase at later hours when both SSW events are evolving.
AB - The magnetic field records of the magnetometer networks in the American, East Asian-Australian, and European-African sectors were employed in this present work. We used them to investigate equatorial electrojet (EEJ), counter electrojet (CEJ), tidal variability in EEJ strength and ionospheric current during the 2005/2006 and 2008/2009 sudden stratospheric warming (SSW) events. In addition to the well-investigated tidal variability in EEJ strength over the American and East Asian sectors, we investigated that of the African sector for the first time. Interestingly, the tidal components in EEJ strength during both SSW events clearly exhibit marked longitudinal differences with high, moderate, and low amplitudes in the American, East Asian, and African sectors, respectively. An exception found around day 71 in the African sector after the 2008/2009 SSW event had higher solar diurnal tidal component as compared to that of the Asian sector. Over the American sector, solar and lunar semidiurnal tides were strongly associated with CEJ current during both SSW events, whereas at the African and East Asian sectors such variabilities are not evident. A solar diurnal tidal component was strongly related to a reduction in the EEJ strength over the East Asian sector. In addition, a prolonged period of CEJ occurrence that begins during the SSW precondition and ends when the SSW was evolving characterized the African sector during both SSW events. There is a steady shift in phase at later hours when both SSW events are evolving.
UR - http://www.scopus.com/inward/record.url?scp=85069926674&partnerID=8YFLogxK
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U2 - 10.1029/2019JA026667
DO - 10.1029/2019JA026667
M3 - Article
AN - SCOPUS:85069926674
VL - 124
SP - 6156
EP - 6172
JO - Journal of Geophysical Research
JF - Journal of Geophysical Research
SN - 0148-0227
IS - 7
ER -