TY - JOUR
T1 - The Persistent Ionospheric Responses Over Japan After the Impact of the 2011 Tohoku Earthquake
AU - Chou, Min Yang
AU - Cherniak, Iurii
AU - Lin, Charles C.H.
AU - Pedatella, N. M.
N1 - Funding Information:
This study is supported by National Science Foundation Grant AGS-1522830. This material is based upon work supported by the National Center for Atmospheric Research, which is a major facility sponsored by the National Science Foundation under Cooperative Agreement 1852977. Continued Operation of COSMIC GPS Radio Occultation Constellation in Support of Research Applications in Atmospheric Sciences. CHL was supported by University Advancement Project of NCKU. The FORMOSAT-3/COSMIC data were obtained from the COSMIC Data Analysis and Archive Center (CDAAC, http://cdaac-www.cosmic.ucar.edu) database. The ground-based GNSS data were provided by the Geospatial Information Authority of Japan (GEONET, http://www.gsi.go.jp/ENGLISH/index.html). The authors acknowledge the National Institute of Information and Communications Technology (NICT) for providing ionograms (http://wdc.nict.go.jp/IONO/HP2009/ISDJ/) and National Oceanic and Atmospheric Administration's National Geophysical Data Center (NOAA's NGDC) for providing DART data (https://www.ngdc.noaa.gov/).
Funding Information:
This study is supported by National Science Foundation Grant AGS‐1522830. This material is based upon work supported by the National Center for Atmospheric Research, which is a major facility sponsored by the National Science Foundation under Cooperative Agreement 1852977. Continued Operation of COSMIC GPS Radio Occultation Constellation in Support of Research Applications in Atmospheric Sciences. CHL was supported by University Advancement Project of NCKU. The FORMOSAT‐3/COSMIC data were obtained from the COSMIC Data Analysis and Archive Center (CDAAC, http://cdaac‐www.cosmic.ucar.edu ) database. The ground‐based GNSS data were provided by the Geospatial Information Authority of Japan (GEONET, http://www.gsi.go.jp/ENGLISH/index.html ). The authors acknowledge the National Institute of Information and Communications Technology (NICT) for providing ionograms ( http://wdc.nict.go.jp/IONO/HP2009/ISDJ/ ) and National Oceanic and Atmospheric Administration's National Geophysical Data Center (NOAA's NGDC) for providing DART data ( https://www.ngdc.noaa.gov/ ).
Publisher Copyright:
© 2020. The Authors.
PY - 2020/4/1
Y1 - 2020/4/1
N2 - In this study, we report the persistent impacts of the 2011 Tohoku earthquake/tsunami on the ionosphere using the ground-based Global Navigation Satellite System and FORMOSAT-3/COSMIC total electron content. Multiple unusual ionospheric phenomena, such as ionospheric irregularities, nighttime medium-scale traveling ionospheric disturbances (MSTIDs), and planar traveling ionospheric disturbances (TIDs), were observed after the emergence of tsunami-induced concentric gravity waves. The ionospheric irregularities initially developed over the Hokkaido region following the interference of gravity waves at ~8:45 UT. Remarkably, the Perkins-type nighttime MSTIDs accompanying the planar TIDs were discernible over Japan following the irregularities. By comparing with the tsunami model simulation and ocean buoy observations, it is determined that these planar TIDs, lasting for about 10 hr, were likely related to tsunami ocean waves reflected by seamounts, ridges, islands, and seafloor topography in the Pacific Ocean. Due to the absence of sporadic E layers, we suggest that the coupling between the tsunami-generated gravity waves and the Perkins instability plays an essential role in initiating the equinoctial nighttime MSTIDs. The long-lasting tsunami can continuously impact the ionosphere, affecting the nighttime ionospheric electrodynamics and making the conditions conducive for the development of midlatitude nighttime ionospheric irregularities and instabilities.
AB - In this study, we report the persistent impacts of the 2011 Tohoku earthquake/tsunami on the ionosphere using the ground-based Global Navigation Satellite System and FORMOSAT-3/COSMIC total electron content. Multiple unusual ionospheric phenomena, such as ionospheric irregularities, nighttime medium-scale traveling ionospheric disturbances (MSTIDs), and planar traveling ionospheric disturbances (TIDs), were observed after the emergence of tsunami-induced concentric gravity waves. The ionospheric irregularities initially developed over the Hokkaido region following the interference of gravity waves at ~8:45 UT. Remarkably, the Perkins-type nighttime MSTIDs accompanying the planar TIDs were discernible over Japan following the irregularities. By comparing with the tsunami model simulation and ocean buoy observations, it is determined that these planar TIDs, lasting for about 10 hr, were likely related to tsunami ocean waves reflected by seamounts, ridges, islands, and seafloor topography in the Pacific Ocean. Due to the absence of sporadic E layers, we suggest that the coupling between the tsunami-generated gravity waves and the Perkins instability plays an essential role in initiating the equinoctial nighttime MSTIDs. The long-lasting tsunami can continuously impact the ionosphere, affecting the nighttime ionospheric electrodynamics and making the conditions conducive for the development of midlatitude nighttime ionospheric irregularities and instabilities.
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U2 - 10.1029/2019SW002302
DO - 10.1029/2019SW002302
M3 - Article
AN - SCOPUS:85083966407
SN - 1542-7390
VL - 18
JO - Space Weather
JF - Space Weather
IS - 4
M1 - e2019SW002302
ER -