| Texto completo | |
| Autor(es): |
Li, Guozhu
[1, 2]
;
Ning, Baiqi
[1, 3]
;
Wang, Chi
[4]
;
Abdu, M. A.
[5]
;
Otsuka, Yuichi
[6]
;
Yamamoto, M.
[7]
;
Wu, Jian
[8]
;
Chen, Jinsong
[8]
Número total de Autores: 8
|
| Afiliação do(s) autor(es): | [1] Chinese Acad Sci, Inst Geol & Geophys, Key Lab Earth & Planetary Phys, Beijing - Peoples R China
[2] Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing - Peoples R China
[3] Chinese Acad Sci, Inst Geol & Geophys, Beijing Natl Observ Space Environm, Beijing - Peoples R China
[4] Chinese Acad Sci, Natl Space Sci Ctr, State Key Lab Space Weather, Beijing - Peoples R China
[5] INPE, Sao Jose Dos Campos - Brazil
[6] Nagoya Univ, Inst Space Earth Environm Res, Nagoya, Aichi - Japan
[7] Kyoto Univ, Res Inst Sustainable Humanosphere, Uji, Kyoto - Japan
[8] Res Inst Radio Wave Propagat, Natl Key Lab Electromagnet Environm, Qingdao - Peoples R China
Número total de Afiliações: 8
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS; v. 123, n. 9, p. 7985-7998, SEP 2018. |
| Citações Web of Science: | 4 |
| Resumo | |
Storm time development of equatorial plasma bubbles (EPBs) around the meridian 120 degrees E/60 degrees W during early September 2017, when the Bz component of interplanetary magnetic field (IMF) experienced two large southward excursions, producing a strong geomagnetic storm that included two main phase decreases, was investigated. The observations from networks of Global Navigation Satellite Systems total electron content receivers, very high frequency radars, and ionosondes operated around the meridian reveal that in the American and Asian sectors, intense EPB irregularities developed and extended to dip latitudes of similar to 30 degrees N and 46 degrees N, respectively, following rapid sunset F layer height rises during two episodes of strong southward IMF Bz excursions. The storm-enhanced EPB irregularities, however, were not observed following the sunset terminator in the Pacific sector, where the sunset rise of F layer was not detected. More interestingly, the EPBs in the Asian sector were observed to drift toward the west, with velocity increasing from similar to 30 m/s at low latitude to similar to 95 m/s at middle latitude. The poleward increasing westward drifts drove the formation of west-titled structure of irregularities. For the EPBs in the American sector, no apparent west-tilted structure was detected. The results indicate that the prompt penetration undershielding electric fields (PPEF) of eastward polarity resulting from the two IMF Bz southward excursions dominated the generation of postsunset EPBs in the American and Asian sectors, respectively. The westward drifts of PPEF-induced EPBs in the Asian sector could be attributed dominantly to disturbance westward wind, with a possible contribution to it arising from the PPEF. Plain Language Summary The development and evolution of equatorial plasma bubbles (EPBs) exhibit complex global behavior during geomagnetic storms. In recent years, an international space weather meridian circle program, which aims to provide a global picture of unfolding space weather events by using diverse instruments along the approximate meridian 120 degrees E/60 degrees W, that is, the Asian and American longitude sectors, was launched. Considering the sunset interval (similar to 12 hr) between the two longitudes, it is expected that the development of postsunset EPBs, if enhanced in one region by short-lived prompt penetration electric fields (PPEF), would be inhibited in the other region under the delayed and long duration effect of disturbance dynamo electric fields. Here we report a unique case of significantly enhanced postsunset EPBs developments by PPEF in both the American and Asian sectors, but their total absence by disturbance dynamo electric fields in the Pacific sector during the September 2017 geomagnetic storm sequence. Moreover, the PPEF-induced EPBs along the meridian show different characteristics, with apparent west-tilted structure in the Asian sector but not in the American sector. This sort of study based on the international space weather meridian circle program observations will strengthen our understanding on the generation and evolution characteristics of EPBs during geomagnetic storms. (AU) | |
| Processo FAPESP: | 16/24970-7 - Programa de Pesquisa de Observação e Previsão da Cintilação (SPORT) |
| Beneficiário: | Mangalathayil Ali Abdu |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |