Articles | Volume 32, issue 7
https://doi.org/10.5194/angeo-32-831-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/angeo-32-831-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Regular paper
| 
23 Jul 2014
Regular paper |
| 23 Jul 2014
Extreme ion heating in the dayside ionosphere in response to the arrival of a coronal mass ejection on 12 March 2012
H. Fujiwara
Faculty of Science and Technology, Seikei University, Tokyo, Japan
S. Nozawa
Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, Japan
Y. Ogawa
National Institute of Polar Research, Tokyo, Japan
R. Kataoka
National Institute of Polar Research, Tokyo, Japan
Y. Miyoshi
Department of Earth and Planetary Sciences, Kyushu University, Fukuoka, Japan
H. Jin
National Institute of Communication Technology, Tokyo, Japan
H. Shinagawa
National Institute of Communication Technology, Tokyo, Japan
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Hiroko Miyahara, Yasuyuki Aono, and Ryuho Kataoka
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Nickolay Ivchenko, Nicola M. Schlatter, Hanna Dahlgren, Yasunobu Ogawa, Yuka Sato, and Ingemar Häggström
Ann. Geophys., 35, 1143–1149, https://doi.org/10.5194/angeo-35-1143-2017, https://doi.org/10.5194/angeo-35-1143-2017, 2017
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Photo-electrons and secondary electrons from particle precipitation enhance the incoherent scatter plasma line to levels sufficient for detection. A plasma line gives an accurate measure of the electron density and can be used to estimate electron temperature. The occurrence of plasma line enhancements in the EISCAT Svalbard Radar data was investigated. During summer daytime hours the plasma line is detectable in up to 90 % of the data. In winter time the occurrence is a few percent.
Hiroko Miyahara, Chika Higuchi, Toshio Terasawa, Ryuho Kataoka, Mitsuteru Sato, and Yukihiro Takahashi
Ann. Geophys., 35, 583–588, https://doi.org/10.5194/angeo-35-583-2017, https://doi.org/10.5194/angeo-35-583-2017, 2017
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Detailed analyses of the 27-day solar rotational period in cloud and lightning activities may help in untangling the process of solar influence on weather and climate. We analyzed the lightning data in Japan for AD 1989–2015 and found that the 27-day solar rotational period is seen in wide-area lightning activity. The signal was stronger at the maxima of solar decadal cycles. It was also found that the signal of the 27-day period migrates from the southwest to the northeast in Japan.
R. Kataoka, Y. Fukuda, H. A. Uchida, H. Yamada, Y. Miyoshi, Y. Ebihara, H. Dahlgren, and D. Hampton
Ann. Geophys., 34, 41–44, https://doi.org/10.5194/angeo-34-41-2016, https://doi.org/10.5194/angeo-34-41-2016, 2016
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T. Takahashi, S. Nozawa, T. T. Tsuda, Y. Ogawa, N. Saito, T. Hidemori, T. D. Kawahara, C. Hall, H. Fujiwara, N. Matuura, A. Brekke, M. Tsutsumi, S. Wada, T. Kawabata, S. Oyama, and R. Fujii
Ann. Geophys., 33, 941–953, https://doi.org/10.5194/angeo-33-941-2015, https://doi.org/10.5194/angeo-33-941-2015, 2015
T. Ishida, Y. Ogawa, A. Kadokura, K. Hosokawa, and Y. Otsuka
Ann. Geophys., 33, 525–530, https://doi.org/10.5194/angeo-33-525-2015, https://doi.org/10.5194/angeo-33-525-2015, 2015
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We studied the localized plasma density enhancements called blobs, which are often produced in the high-latitude ionosphere by the transportation process of plasma or particle precipitations. This subject is important because such structures affect radio wave propagation and can cause scintillation of GNSS signals in the deformation process. This paper is the first report of direct observations of blob deformation during a substorm.
R. Kataoka, Y. Nakagawa, and T. Sato
Ann. Geophys., 33, 75–78, https://doi.org/10.5194/angeo-33-75-2015, https://doi.org/10.5194/angeo-33-75-2015, 2015
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Using a new air-shower simulation driven by the proton flux data obtained from GOES satellites, we show the possibility of significant enhancement of the effective dose rate of up to 4.5 µSv/hr at a conventional flight altitude of 12 km during the largest solar proton event that did not cause a ground-level enhancement. As a result, a new GOES-driven model is proposed to give an estimate of the contribution from the isotropic component of the radiation dose in the stratosphere.
T. Takahashi, S. Nozawa, M. Tsutsumi, C. Hall, S. Suzuki, T. T. Tsuda, T. D. Kawahara, N. Saito, S. Oyama, S. Wada, T. Kawabata, H. Fujiwara, A. Brekke, A. Manson, C. Meek, and R. Fujii
Ann. Geophys., 32, 1195–1205, https://doi.org/10.5194/angeo-32-1195-2014, https://doi.org/10.5194/angeo-32-1195-2014, 2014
R. Kataoka, Y. Miyoshi, K. Shigematsu, D. Hampton, Y. Mori, T. Kubo, A. Yamashita, M. Tanaka, T. Takahei, T. Nakai, H. Miyahara, and K. Shiokawa
Ann. Geophys., 31, 1543–1548, https://doi.org/10.5194/angeo-31-1543-2013, https://doi.org/10.5194/angeo-31-1543-2013, 2013
