@Article{LiNWAOYWC:2018:StDePo,
author = "Li, Guozhu and Ning, Baiqi and Wang, Chi and Abdu, Mangalathayil
Ali and Otsuka, Yuichi and Yamamoto, M. and Wu, Jian and Chen,
Jinsong",
affiliation = "{Chinese Academy of Sciences} and {Chinese Academy of Sciences}
and {Chinese Academy of Sciences} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Nagoya University} and {Kyoto
University} and {Research Institute of Radio Wave Propagation} and
{Research Institute of Radio Wave Propagation}",
title = "Storm-enhanced development of postsunset equatorial plasma bubbles
around the meridian 120 degrees E/60 degrees W on 7-8 September
2017",
journal = "Journal of Geophysical Research: Space Physics",
year = "2018",
volume = "123",
number = "9",
pages = "7985--7998",
month = "Sept.",
keywords = "equatorial plasma bubbles, geomagnetic storm, disturbance electric
field, west-tilted structure, westward drifts, international space
weather meridian circle program.",
abstract = "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.",
doi = "10.1029/2018JA025871",
url = "http://dx.doi.org/10.1029/2018JA025871",
issn = "2169-9402",
language = "en",
targetfile = "li-storm.pdf",
urlaccessdate = "03 jun. 2024"
}