Publication List of Refereed Journals


  1. Otsuka, Y., Abadi, P., Hozumi, K., and Almahi, A. (2023). Equinoctial asymmetry of plasma bubble occurrence and electric field at evening: GPS and ionosonde measurements in Southeast Asia, Journal of Atmospheric and Solar-Terrestrial Physics, 252, https://doi.org/10.1016/j.jastp.2023.106136.
  2. Otsuka, Y., Spogli, L., Tulasi Ram, S., and Li, G. Z. (2021). Preface to the Special Issue on recent advances in the study of Equatorial Plasma Bubbles and Ionospheric Scintillation. Earth Planet. Phys., 5(5), 365
  3. Otsuka, Y., Shinbori, A., Sori, T., Tsugawa, T., Nishioka, M., and Huba, J. D. (2021). Plasma depletions lasting into daytime during the recovery phase of a geomagnetic storm in May 2017: Analysis and simulation of GPS total electron content observations. Earth Planet. Phys., 5(5), 427, http://doi.org/10.26464/epp2021046 (Web Publishing Date: 2021-08-23)
  4. Otsuka, Y. (2021). Medium-Scale Traveling Ionospheric Disturbances. In Ionosphere Dynamics and Applications (eds C. Huang, G. Lu, Y. Zhang and L.J. Paxton). https://doi.org/10.1002/9781119815617.ch18 (First published:24 March 2021)

  5. Otsuka, Y., Shinbori, A., Tsugawa, T., and Nishioka, M., Solar activity dependence of medium-scale traveling ionospheric disturbances using GPS receivers in Japan. Earth Planets Space 73, 22 (2021). https://doi.org/10.1186/s40623-020-01353-5 (Published: 20 January 2021)

  6. Otsuka, Y., Review for Generation Mechanisms of Post-Midnight Irregularities in Equatorial and Low-Latitude Ionosphere, Progress in Earth and Planetary Science, 5, 57, https://doi.org/10.1186/s40645-018-0212-7, 2018.

  7. Otsuka Y., Mizutani, N., Shiokawa, K., Patra, A., Yokoyama, T., and Yamamoto, M., Drift Velocities of 150-km Field-Aligned Irregularities Observed by the Equatorial Atmosphere Radar (in Japanese), Antarctic Record, 57(3), 369-378, 2013. (大塚雄一, 水谷徳仁, 塩川和夫, Amit Patra, 横山竜宏, 山本衛, 赤道大気レーダーを用いた高度150km沿磁力線不規則構造のドリフト速度に関する研究 南極資料, 57(3), 369-378, 2013)

  8. Otsuka, Y., Suzuki, K., Nakagawa, S., Nishioka, M., Shiokawa, K., and Tsugawa, T.: GPS observations of medium-scale traveling ionospheric disturbances over Europe, Ann. Geophys., 31, 163-172, doi:10.5194/angeo-31-163-2013, 2013. (published: 5 February 2013)

  9. Otsuka, Y., K. Shiokawa, and T. Ogawa (2012), Disappearance of equatorial plasma bubble after interaction with mid-latitude medium-scale traveling ionospheric disturbance, Geophys. Res. Lett., 39, L14105, doi:10.1029/2012GL052286. (published 28 July 2012)

  10. Otsuka, Y. (2012), Seasonal and Local Time Variations of E-Region Field-Aligned Irregularities Observed with 30.8-MHz Radar at Kototabang, Indonesia, International Journal of Geophysics, vol. 2012, 695793, doi:10.1155/2012/695793. (Accepted 15 March 2012)

  11. Otsuka, Y., K. Shiokawa, M. Nishioka and Effendy (2012), VHF Radar Observations of Post-Midnight F-Region Field-Aligned Irregularities over Indonesia during Solar Minimum, Indian Journal of Radio and Space Physics (IJRSP), 41, 199-207 (published April 2012).

  12. Otsuka, Y., N. Kotake, K. Shiokawa, T. Ogawa, T. Tsugawa, and A. Saito, Statistical Study of Medium-Scale Traveling Ionospheric Disturbances Observed with a GPS Receiver Network in Japan, Aeronomy of the Earth's Atmosphere and Ionosphere IAGA Special Sopron Book Series, 2011, Volume 2, Part 3, 291-299, DOI: 10.1007/978-94-007-0326-1_21

  13. Otsuka, Y., K. Shiokawa, T. Ogawa, T. Yokoyama, and M. Yamamoto (2009), Spatial relationship of nighttime medium-scale traveling ionospheric disturbances and F region field-aligned irregularities observed with two spaced all-sky airglow imagers and the middle and upper atmosphere radar, J. Geophys. Res., 114, A05302, doi:10.1029/2008JA013902. (published 8 May 2009.)

  14. Otsuka, Y., T. Ogawa, and Effendy (2009), VHF radar observations of nighttime F-region field-aligned irregularities over Kototabang, Indonesia, Earth Planets Space, 61, 4, 431-437. (Online published May 14, 2009)

  15. Otsuka, Y., T. Tani, T. Tsugawa, and T. Ogawa, Statistical study of relationship between medium-scale traveling ionospheric disturbance and sporadic E layer activities in summer night over Japan, J. Atmos. Solar-Terr. Phys., 70, 2196-2202, 2008. (December 2008)

  16. Otsuka, Y., F. Onoma, K. Shiokawa, T. Ogawa, M. Yamamoto, and S. Fukao, Simultaneous observations of nighttime medium-scale traveling ionospheric disturbances and E-region field-aligned irregularities at midlatitude, J. Geophys. Res., 112, A06317, doi:10.1029/2005JA011548, 2007.

  17. Otsuka, Y., K. Shiokawa, and T. Ogawa, Equatorial ionospheric scintillations and zonal irregularity drifts observed with closely-spaced GPS receivers in Indonesia, J. Meteor. Soc. Japan, 84A, 343-351, 2006.

  18. Otsuka, Y., N. Kotake, T. Tsugawa, K. Shiokawa, T. Ogawa, Effendy, S. Saito, M. Kawamura, T. Maruyama, N. Hemmakorn, and T. Komolmis, GPS detection of total electron content variations over Indonesia and Thailand following the 26 December 2004 earthquake, Earth Planets Space, 58, 159-165, 2006.

  19. Otsuka, Y., T. Aramaki, T. Ogawa, and A. Saito, A statistical study of ionospheric irregularities observed with a GPS network in Japan, Corotating Solar Wind Streams and Recurrent Geomagnetic Activity, Geophys. Monogr., pp. 271-281, Amer. Geophys. Union, 2006.

  20. Otsuka, Y., K. Shiokawa, T. Ogawa, T. Yokoyama, M. Yamamoto, and S. Fukao, Spatial relationship of equatorial plasma bubbles and field-aligned irregularities observed with an all-sky airglow imager and the Equatorial Atmosphere Radar, Geophys. Res. Lett., 31, L20802, 10.1029/2004GL020869, 2004.

  21. Otsuka, Y., K. Shiokawa, T. Ogawa, and P. Wilkinson, Geomagnetic conjugate observations of medium-scale traveling ionospheric disturbances at midlatitude using all-sky airglow imagers, Geophys. Res. Lett., 31, L15803, doi:10.1029/2004GL020262, 2004.

  22. Otsuka, Y., T. Kadota, K. Shiokawa, T. Ogawa, S. Kawamura,, S. Fukao, and S. -R. Zhang, Optical and radio measurements of a 630-nm enhancement over Japan on September 9, 1999, J. Geophys. Res., 108(A6), 1252, doi:10.1029/2002JA009594, 2003.

  23. Otsuka, Y., K. Shiokawa, T. Ogawa, and P. Wilkinson, Geomagnetic conjugate observations of equatorial airglow depletions, Geophys. Res. Lett., 29, 10.1029/2002GL015347, 2002.

  24. Otsuka, Y., T. Ogawa, A. Saito, T. Tsugawa, S. Fukao, and S. Miyazaki, A new technique for mapping of total electron content using GPS network in Japan, Earth, Planets, and Space, 54, 63-70, 2002.

  25. Otsuka, Y., S. Kawamura, N. Balan, S. Fukao, and G.J. Bailey, Plasma temperature variations in the ionosphere over the middle and upper atmosphere radar, J. Geophys. Res., 103, 20,705-20,713, 1998.

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  1. Figueiredo, C. A. O. B., Wrasse, C. M., Vadas, S., Takahashi, H., Otsuka, Y., Nyassor, P. K., et al. (2023). Daytime medium scale traveling ionospheric disturbances (MSTIDS) over the Andes Mountains at equatorial and low magnetic latitudes. Journal of Geophysical Research: Space Physics, 128, e2023JA031477. https://doi.org/10.1029/2023JA031477
  2. Hiroyuki Nakata, Keisuke Hosokawa, Susumu Saito, Yuichi Otsuka & Ichoro Tomizawa, Periodic oscillations of Doppler frequency excited by the traveling ionospheric disturbances associated with the Tonga eruption in 2022. Earth Planets Space 75, 158 (2023). https://doi.org/10.1186/s40623-023-01914-4
  3. Suneetha Emmela, Venkata Ratnam Devanaboyina, Otsuka Yuichi, Atsuki Shinbori, Sori Takuya, Nishioka Michi, Perwitasari Septi, Article Title: An Extreme Value Analysis of Long-term GNSS Ionospheric Total Electron Content Data Observed at Japan Grid Point Location (34.95^oN and 134.^oE), GRSL-00139-2023 IEEE Trans. on Geoscience and Remote Sensing
  4. H. Takahashi, C. A. O. B. Figueiredo, D. Barros, C. M. Wrasse, G. A. Giongo, R. H. Honda, L. F. R. Vital, L. C. A. Resende, P. K. Nyassor, T. T. Ayorinde, C. S. Carmo, M. B. Padua & Y. Otsuka, Ionospheric disturbances over South America related to Tonga volcanic eruption. Earth Planets Space 75, 92 (2023). https://doi.org/10.1186/s40623-023-01844-1 (Published: 25 May 2023)
  5. Atsuki Shinbori, Takuya Sori, Yuichi Otsuka, Michi Nishioka, Septi Perwitasari, Takuo Tsuda, Atsushi Kumamoto, Fuminori Tsuchiya, Shoya Matsuda, Yoshiya Kasahara, Ayako Matsuoka, Satoko Nakamura, Yoshizumi Miyoshi and Iku Shinohara, Generation of equatorial plasma bubble after the 2022 Tonga volcanic eruption. Sci Rep 13, 6450 (2023). https://doi.org/10.1038/s41598-023-33603-3, (Published: 22 May 2023)
  6. Shohei Nishimoto, Kyoko Watanabe, Hidekatsu Jin, Toshiki Kawai, Shinsuke Imada, Tomoko Kawate, Yuichi Otsuka, Atsuki Shinbori, Takuya Tsugawa, and Michi Nishioka, Statistical analysis for EUV dynamic spectra and their impact on the ionosphere during solar flares. Earth Planets Space 75, 30 (2023). https://doi.org/10.1186/s40623-023-01788-6 (Published: 03 March 2023)
  7. Kawai, K., Shiokawa, K., Otsuka, Y., Oyama, S., Connors, M. G., Kasahara, Y., et al. (2023). Multi-event analysis of magnetosphere-ionosphere coupling of nighttime medium-scale traveling ionospheric disturbances from the ground and the Arase satellite. Journal of Geophysical Research: Space Physics, 128, e2022JA030542. https://doi.org/10.1029/2022JA030542 (First published: 18 January 2023)
  8. Jie Liu, Kazuo Shiokawa, Shin-Ichiro Oyama, Yuichi Otsuka, Chae-Woo Jun, Masahito Nosé, Tsutomu Nagatsuma, Kaori Sakaguchi, Akira Kadokura, Mitsunori Ozaki, Martin Connors, Dmitry Baishev, Nozomu Nishitani, Alexey Oinats, Vladimir Kurkin, Tero Raita, (2023). A statistical study of longitudinal extent of Pc1 pulsations using seven PWING ground stations at subauroral latitudes. Journal of Geophysical Research: Space Physics, 128, e2021JA029987. https://doi.org/10.1029/2021JA029987 (First published: 09 January 2023)
  9. Mitsunori Ozaki, Kazuo Shiokawa, Ryuho Kataoka, Martin Mlynczak, Larry Paxton, Martin Connors, Satoshi Yagitani, Shion Hashimoto, Yuichi Otsuka, Satoshi Nakahira and Ian Mann, Localized mesospheric ozone destruction corresponding to isolated proton aurora coming from Earth’s radiation belt. Sci Rep 12, 16300 (2022). https://doi.org/10.1038/s41598-022-20548-2Localized mesospheric ozone destruction corresponding to isolated proton aurora coming from Earth’s radiation belt. Sci Rep 12, 16300 (2022). https://doi.org/10.1038/s41598-022-20548-2 (Published: 11 October 2022)
  10. Hideto Naito, Kazuo Shiokawa, Yuichi Otsuka, Hatsuki Fujinami, Takuma Tsuboi, Takeshi Sakanoi, Akinori Saito, Takuji Nakamura (2022). Three-dimensional Fourier analysis of atmospheric gravity waves and medium-scale traveling ionospheric disturbances observed in airglow images in Hawaii over three years. Journal of Geophysical Research: Space Physics, 127, e2022JA030346. https://doi.org/10.1029/2022JA030346 (First published: 19 September 2022)
  11. Song, H., Park, J., Jin, Y., Otsuka, Y., Buchert, S., Lee, J., & Yi, Y. (2023). Tandem observations of nighttime mid-latitude topside ionospheric perturbations. Space Weather, 21, e2022SW003312. https://doi.org/10.1029/2022SW003312 (First published: 14 February 2023)
  12. Sori, T., Otsuka, Y., Shinbori, A. et al. Geomagnetic conjugacy of plasma bubbles extending to mid-latitudes during a geomagnetic storm on March 1, 2013. Earth Planets Space 74, 120 (2022). https://doi.org/10.1186/s40623-022-01682-7 (Published: 06 August 2022)
  13. Akala, A.O., Afolabi, R.O., and Otsuka, Y (2022), Responses of the African-European equatorial-, low-, mid-, and high-latitude ionosphere to geomagnetic storms of 2013, 2015 St Patrick’s Days, 1 June 2013, and 7 October 2015, Advances in Space Research, https://doi.org/10.1016/j.asr.2022.10.029 (Available online 19 October 2022)
  14. Abadi, P.; Ahmad, U.A.; Otsuka, Y.; Jamjareegulgarn, P.; Martiningrum, D.R.; Faturahman, A.; Perwitasari, S.; Saputra, R.E.; Septiawan, R.R. (2022), Modeling Post-Sunset Equatorial Spread-F Occurrence as a Function of Evening Upward Plasma Drift Using Logistic Regression, Deduced from Ionosondes in Southeast Asia. Remote Sens. 2022, 14, 1896. https://doi.org/10.3390/rs14081896.
  15. Yadav, S., Shiokawa, K., Otsuka, Y., and Connors, M., Statistical study of subauroral arc detachment at Athabasca, Canada: New insights on STEVE. Journal of Geophysical Research: Space Physics, 127, e2021JA029856. https://doi.org/10.1029/2021JA029856Yadav, S., Shiokawa, K., Otsuka, Y., & Connors, M. (2022). Statistical study of subauroral arc detachment at Athabasca, Canada: New insights on STEVE. Journal of Geophysical Research: Space Physics, 127, e2021JA029856. https://doi.org/10.1029/2021JA029856, 2022.(First published: 12 September 2022)
  16. Srisamoodkham, W., Shiokawa, K., Otsuka, Y., Ansari, K., Jamjareegulgarn, P., Detecting Equatorial Plasma Bubbles on All-Sky Imager Images Using Convolutional Neural Network. In: Sharma, H., Shrivastava, V., Kumari Bharti, K., Wang, L. (eds) Communication and Intelligent Systems . Lecture Notes in Networks and Systems, vol 461. Springer, Singapore. https://doi.org/10.1007/978-981-19-2130-8_38, 2022. (First Online: 19 August 2022)
  17. Shinbori, A., Otsuka, Y., Sori, T., Nishioka, M., Perwitasari, S., Tsuda, T., and Nishitani, N., Electromagnetic conjugacy of ionospheric disturbances after the 2022 Hunga Tonga-Hunga Ha’apai volcanic eruption as seen in GNSS-TEC and SuperDARN Hokkaido pair of radars observations. Earth Planets Space 74, 106, https://doi.org/10.1186/s40623-022-01665-8, 2022.
  18. Iyemori, T., Nishioka, M., Otsuka, Y. and Shinbori, A., A confirmation of vertical acoustic resonance and field-aligned current generation just after the 2022 Hunga Tonga Hunga Ha’apai volcanic eruption. Earth Planets Space 74, 103, https://doi.org/10.1186/s40623-022-01653-y, 2022.
  19. Sori, T., Shinbori, A., Otsuka, Y., Tsugawa, T., Nishioka, M., & Yoshikawa, A. (2022). Generation mechanisms of plasma density irregularity in the equatorial ionosphere during a geomagnetic storm on 21-22 December 2014. Journal of Geophysical Research: Space Physics, 127, e2021JA00240. https://doi.org/10.1029/30240. https://doi.org/10.1029/2021JA030240 (First published: 02 May 2022)
  20. Mani Sivakandan, Carlos Martinis, Yuichi Otsuka, Jorge L. Chau, Jessica Norrell, Jens Mielich, J. Federico Conte, Claudia Stolle, J. Rodríguez-Zuluaga, Atsuki Shinbori, Michi Nishioka, Takuya Tsugawa, On the role of E-F region coupling in the generation of nighttime MSTIDs during summer and equinox: Case studies over northern Germany, Journal of Geophysical Research: Space Physics, 10.1029/2021JA030159, 2022.236. (First published: 12 May 2022)
  21. Ryo Matsushima, Keisuke Hosokawa, Jun Sakai, Yuichi Otsuka, Mitsumu K. Ejiri, Michi Nishioka and Takuya Tsugawa, Propagation characteristics of sporadic E and medium-scale traveling ionospheric disturbances (MSTIDs): statistics using HF Doppler and GPS-TEC data in Japan. Earth Planets Space 74, 60 (2022). https://doi.org/10.1186/s40623-022-01616-3 (Published: 24 April 2022)
  22. Shinbori, A., Otsuka, Y., Sori, T., Tsugawa, T., & Nishioka, M. (2022). Statistical behavior of large-scale ionospheric disturbances from high latitudes to mid-latitudes during geomagnetic storms using 20-yr GNSS-TEC data: Dependence on season and storm intensity. Journal of Geophysical Research: Space Physics, 127, e2021JA029687. https://doi.org/10.1029/2021JA029687 (First published: 11 January 2022)

  23. Septi Perwitasari, Takuji Nakamura, Takuya Tsugawa, Michi Nishioka, Yoshihiro Tomikawa, Mitsumu K. Ejiri, Masaru Kogure, Yuichi Otsuka, Atsuki Shinbori, Hidekatsu Jin, Chihiro Tao (2022). Propagation direction analyses of medium-scale traveling ionospheric disturbances observed over North America with GPS-TEC perturbation maps by three-dimensional spectral analysis method. Journal of Geophysical Research: Space Physics, 127, e2020JA028791. https://doi.org/10.1029/2020JA028791 (First published: 10 January 2022)

  24. Kozo Hashimoto, Atsuki Shinbori, Yuichi Otsuka, Fuminori Tsuchiya, Atsushi Kumamoto, Yoshiya Kasahara, Ayako Matsuoka, Isamu Nagano, Yoshizumi Miyoshi, Tatsuhiro Yokoyama (2021). Propagation mechanism of medium wave broadcasting waves observed by the Arase satellite: Hectometric line spectra. Journal of Geophysical Research: Space Physics, 126, e2021JA029813. https://doi.org/10.1029/2021JA029813 (First published: 21 October 2021)

  25. Takahashi, H., Essien, P., Figueiredo, C. A. O. B., Wrasse, C. M., Barros, D., Abdu, M. A., Otsuka, Y., Shiokawa, K., and Li, G. Z. (2021). Multi-instrument study of longitudinal wave structures for plasma bubble seeding in the equatorial ionosphere. Earth Planet. Phys., 5(5), 368, http://doi.org/10.26464/epp202104 (First published: 22 0240. https://doi.org/10.1029/2021JA030240October 2021)

  26. Abadi, P., Otsuka, Y., Liu, H. X., Hozumi, K., Martinigrum, D. R., Jamjareegulgarn, P., Thanh, L. T, and Otadoy, R. (2021). Roles of thermospheric neutral wind and equatorial electrojet in pre-reversal enhancement, deduced from observations in Southeast Asia. Earth Planet. Phys., 5(5), 387, http://doi.org/10.26464/epp2021049 (Web Publishing Date: 2021-09-10)

  27. Hyangpyo Kim, Kazuo Shiokawa, Jaeheung Park, Yoshizumi Miyoshi, Yukinaga Miyashita, Claudia Stolle, Hyunju Kim Connor, Junga Hwang, Stephan Buchert, Hyuck-Jin Kwon, Satoko Nakamura, Kohki Nakamura, Shin-Ichiro Oyama, Yuichi Otsuka, Tsutomu Nagatsuma, Kaori Sakaguchi, (2021), Isolated proton aurora driven by EMIC Pc1 wave: PWING, Swarm, and NOAA POES multi-instrument observations. Geophysical Research Letters, 48, e2021GL095090. https://doi.org/10.1029/2021GL095090. (First published: 01 September 2021)

  28. Sato, H., Kim, J. S., Otsuka, Y., Wrasse, C. M., Rodrigues de Paula, E., & Rodrigues de Souza, J. (2021). L-band Synthetic Aperture Radar observation of ionospheric density irregularities at equatorial plasma depletion region. Geophysical Research Letters, 48, e2021GL093541. https://doi.org/10.1029/2021GL093541 (First published: 16 August 2021)

  29. Kusano, K., K. Ichimoto, M. Ishii, Y. Miyoshi, S. Yoden, H. Akiyoshi, A. Asai, Y. Ebihara, H. Fujiwara, T. Goto, Y. Hanaoka, H. Hayakawa, K. Hosokawa, H. Hotta, K. Hozumi, S. Imada, K. Iwai, T. Iyemori1, H. Jin, R. Kataoka, Y. Katoh, T. Kikuchi, Y. Kubo, S. Kurita, H. Matsumoto, T. Mitani, H. Miyahara, Y. Miyoshi, T. Nagatsuma, A. Nakamizo, S. Nakamura, H. Nakata, N. Nishizuka, Y. Otsuka, S. Saito, S. Saito, T. Sakurai, T. Sato, T. Shimizu, H. Shinagawa, K. Shiokawa, D. Shiota, T. Takashima, C. Tao, S. Toriumi, S. Ueno, K. Watanabe, S. Watari, S. Yashiro, K. Yoshida, and A. Yoshikawa, PSTEP: project for solar-terrestrial environment prediction, Earth, Planets and Space, doi:10.1186/s40623-021-01486-1, 2021. (Published: 05 August 2021)

  30. Panasenko, S.V., Kotov, D.V., Otsuka, Y. et al. Coupled investigations of ionosphere variations over European and Japanese regions: observations, comparative analysis, and validation of models and facilities. Prog Earth Planet Sci 8, 45 (2021). https://doi.org/10.1186/s40645-021-00441-8 (Published: 11 August 2021)

  31. Okoh, D. I., A. B. Rabiu, K. Shiokawa, Y. Otsuka, Q. Wu, G. K. Seemala, and Z. T. Katamzi-Joseph, An experimental investigation into the possible connections between the zonal neutral wind speeds and equatorial plasma bubble drift velocities over the African equatorial region, J. Atmos. Solar-Terr. Phys., 220, https://doi.org/10.1016/j.jastp.2021.105663, 2021. (Available online 14 May 2021)

  32. Cheng, PH., Lin, C., Otsuka, Y. et al. Statistical study of medium-scale traveling ionospheric disturbances in low-latitude ionosphere using an automatic algorithm. Earth Planets Space 73, 105 (2021). https://doi.org/10.1186/s40623-021-01432-1 (Published: 13 May 2021)

  33. Sori, T., Shinbori, A., Otsuka, Y., Tsugawa, T., & Nishioka, M. (2021). The occurrence feature of plasma bubbles in the equatorial to midlatitude ionosphere during geomagnetic storms using long-term GNSS-TEC data. Journal of Geophysical Research: Space Physics, 126, e2020JA029010. https://doi.org/10.1029/2020JA029010 (First published: 06 May 2021)

  34. Sarudin, I., Hamid, N. S. A, Abdullah, M., Buhari, S. M, Shiokawa, K., Otsuka, Y., et al. (2021). Influence of zonal wind velocity variation on equatorial plasma bubble occurrences over Southeast Asia. Journal of Geophysical Research: Space Physics, 126, e2020JA028994. https://doi.org/10.1029/2020JA028994 (First published: 05 May 2021)

  35. Shinbori, A., Otsuka, Y., Tsugawa, T., Nishioka, M., Kumamoto, A., Tsuchiya, F., et al. (2021). Relationship between the locations of the midlatitude trough and plasmapause using GNSS-TEC and Arase satellite observation data. Journal of Geophysical Research: Space Physics, 126, e2020JA028943. https://doi.org/10.1029/2020JA028943 (First published: 15 April 2021)
  36. Nakamura, K., Shiokawa, K., Otsuka, Y., Shinbori, A., Miyoshi, Y., Connors, M., et al. (2021). Simultaneous observation of two isolated proton auroras at subauroral latitudes by a highly sensitive all-sky camera and Van Allen Probes. Journal of Geophysical Research: Space Physics, 126, e2020JA029078. https://doi.org/10.1029/2020JA029078 (First published: 30 April 2021)
  37. Kyoko Watanabe, Hidekatsu Jin, Shohei Nishimoto, Shinsuke Imada, Toshiki Kawai, Tomoko Kawate, Yuichi Otsuka, Atsuki Shinbori, Takuya Tsugawa & Michi Nishioka, Model-based reproduction and validation of the total spectra of a solar flare and their impact on the global environment at the X9.3 event of September 6, 2017. Earth Planets Space 73, 96 (2021). https://doi.org/10.1186/s40623-021-01376-6 (Published: 20 April 2021)
  38. Currie, J. L., Carter, B. A., Retterer, J., Dao, T., Pradipta, R., Caton, R., Groves, K., Otsuka, Y., Yokoyama, T., Hozumi, K., Le Truong, T., Terkildsen, M., (2021). On the generation of an unseasonal EPB over South East Asia. Journal of Geophysical Research: Space Physics, 126, e2020JA028724. https://doi.org/10.1029/2020JA028724 (First published: 09 February 2021)
  39. Narayanan, V. L., Nozawa, S., Oyama, S.-I., Mann, I., Shiokawa, K., Otsuka, Y., Saito, N., Wada, S., Kawahara, T. D., and Takahashi, T.: Formation of an additional density peak in the bottom side of the sodium layer associated with the passage of multiple mesospheric frontal systems, Atmos. Chem. Phys., 21, 2343-2361, https://doi.org/10.5194/acp-21-2343-2021, 2021. (Published: 18 Feb 2021)
  40. Yudai Inaba Kazuo Shiokawa Shin-ichiro Oyama Yuichi Otsuka Martin Connors Ian Schofield Yoshizumi Miyoshi Shun Imajo Atsuki Shinbori Artem Yu Gololobov Yoichi Kazama Shiang-Yu Wang Sunny W. Y. Tam Tzu-Fang Chang Bo-Jhou Wang Kazushi Asamura Shoichiro Yokota Satoshi Kasahara Kunihiro Keika Tomoaki Hori Ayako Matsuoka Yoshiya Kasahara Atsushi Kumamoto Shoya Matsuda Yasumasa Kasaba Fuminori Tsuchiya Masafumi Shoji Masahiro Kitahara Satoko Nakamura Iku Shinohara Harlan E. Spence Geoff D. Reeves Robert J. Macdowall Charles W. Smith John R. Wygant John W. Bonnell (2021). Multi-event analysis of plasma and field variations in source of stable auroral red (SAR) arcs in inner magnetosphere during non-storm-time substorms. Journal of Geophysical Research: Space Physics, 126, e2020JA029081. https://doi.org/10.1029/2020JA029081 (First published: 12 March 2021)

  41. Yadav, S., Shiokawa, K., Otsuka, Y., Connors, M., & St Maurice, J.‐P. (2021). Multi‐wavelength imaging observations of STEVE at Athabasca, Canada. Journal of Geophysical Research: Space Physics, 126, e2020JA028622. https://doi.org/10.1029/2020JA028622 (First published: 02 February 2021)

  42. Sivakandan, M., Otsuka, Y., Ghosh, P., Shinagawa, H., Shinbori, A., and Miyoshi, Y., Comparison of seasonal and longitudinal variation of daytime MSTID activity using GPS observation and GAIA simulations. Earth Planets Space 73, 35 (2021). https://doi.org/10.1186/s40623-021-01369-5 (Published: 04 February 2021)
  43. Hosokawa, K., M. Nagata, K. Shiokawa, Y. Otsuka, What controls the luminosity of polar cap airglow patches? Implication from airglow measurements in Eureka, Canada in comparison with SuperDARN convection pattern, Polar Science, 100608, 2020. https://doi.org/10.1016/j.polar.2020.100608 (Available online 28 October 2020)
  44. Li, G., Ning, B., Otsuka, Y. et al. Challenges to Equatorial Plasma Bubble and Ionospheric Scintillation Short-Term Forecasting and Future Aspects in East and Southeast Asia. Surv Geophys (2021). https://doi.org/10.1007/s10712-020-09613-5 (Published: 05 September 2020)

  45. Inaba Y., K. Shiokawa, S. Oyama, Y. Otsuka, A. Oksanen, A. Shinbori, A. Yu. Gololobov, Y. Miyoshi, Y. Kazama, S.-Y. Wang, S. W. Y. Tam, T.-F. Chang, B.-J. Wang, S. Yokota, S. Kasahara, K. Keika, T. Hori, A. Matsuoka, Y. Kasahara, A. Kumamoto, Y. Kasaba, M. Shoji, I. Shinohara, and C. Stolle, Plasma and field observations in the magnetospheric source region of a stable auroral red (SAR) arc by the Arase satellite on 28 March 2017, J. Geophys. Res., 125, https://doi.org/10.1029/2020JA028068, 2020.
  46. Takahashi, H., C. M. Wrasse, C. A. O. B. Figueiredo, D. Barros, I. Paulino, P. Essien, M. A. Abdu, Y. Otsuka and K. Shiokawa, Equatorial plasma bubble occurrence under propagation of MSTID and MLT gravity waves, J. Geophys. Res., 125, https://doi.org/10.1029/2019JA027566, 2020. (First published: 30 August 2020)
  47. Yadav S., K. Shiokawa, Y. Otsuka, M. Connors, and J.-P. St. Maurice, Multi-wavelength imaging observations of STEVE at Athabasca, Canada, J. Geophys. Res., 125, https://doi.org/10.1029/2020JA028622, 2020.
  48. Dao, Tam, Huy, Minh, Carter, Brett, Le, Que, Trinh, Thanh, Phan, Bao, AND Otsuka, Yuichi. New observations of the total electron content and ionospheric scintillations over Ho Chi Minh City VIETNAM JOURNAL OF EARTH SCIENCES, (13 July 2020) doi:10.15625/0866-7187/42/4/15281 (published on 05 November 2020 )
  49. F Huang, J Lei, Y Otsuka, X Luan, Y Liu, J Zhong, X Dou, Characteristics of Medium-Scale Traveling Ionospheric Disturbances and Ionospheric Irregularities at Mid-Latitudes Revealed by the Total Electron Content Associated With the Beidou Geostationary Satellite," in IEEE Transactions on Geoscience and Remote Sensing, vol. 59, no. 8, pp. 6424-6430, Aug. 2021, doi: 10.1109/TGRS.2020.3032741. (Date of Publication: 05 November 2020)
  50. Sarudin I., N. S. A. Hamid, M. Abdullah, S. M. Buhari, K. Shiokawa, Y. Otsuka, and C. Y. Yatini, Equatorial plasma bubble zonal drift velocity variations in response to season, local time, and solar activity across Southeast Asia, J. Geophys. Res., 125, doi: 10.1029/2019JA027521, 2020. (First published: 27 February 2020)

  51. Ghosh, P., Y. Otsuka, S. Mani, H. Shinagawa, Day-to-day variation of pre-reversal enhancement in the equatorial ionosphere based on GAIA model simulations. Earth Planets Space 72, 93, https://doi.org/10.1186/s40623-020-01228-9, 2020. (Published on 06 July 2020)

  52. Hosokawa, K., K. Takami, S. Saito, Y. Ogawa, Y. Otsuka, K. Shiokawa, C.-H. Chen, and C.-H. Lin, Observations of equatorial plasma bubbles using a low-cost 630.0-nm all-sky imager in Ishigaki Island, Japan. Earth Planets Space 72, 56 (2020). https://doi.org/10.1186/s40623-020-01187-1

  53. Shinbori, A., Y. Otsuka, T. Sori, T. Tsugawa, and M. Nishioka, Temporal and spatial variations of total electron content enhancements during a geomagnetic storm on 27 and 28 September 2017, J. Geophys. Res., 125, e2019JA026873, doi:10.1029/2019JA026873, 2020.

  54. Tulasi Ram, S.; Ajith, K. K.; Yokoyama, T.; Yamamoto, M.; Hozumi, K.; Shiokawa, K.; Otsuka, Y.; Li, G., (2020) Dilatory and Downward Development of 3-m Scale Irregularities in the Funnel-Like Region of a Rapidly Rising Equatorial Plasma Bubble, Geophysical Research Letters, Volume 47, Issue 13, article id. e87256, (published on July 2020).
  55. Huang, F., Otsuka, Y., Lei, J., Luan, X., Dou, X., & Li, G. (2019). Daytime periodic wave‐like structures in the ionosphere observed at low latitudes over the Asian‐Australian sector using total electron content from Beidou geostationary satellites. Journal of Geophysical Research: Space Physics, 124, 2312? 2322. https://doi.org/10.1029/2018JA026443 (First published: 09 March 2019)
  56. Sivavaraprasad, G, Ratnam, DV, and Otsuka, Y, Multicomponent Analysis of Ionospheric Scintillation Effects Using the Synchrosqueezing Technique for Monitoring and Mitigating their Impact on GNSS Signals, JOURNAL OF NAVIGATION, 72, 669-684, doi: 10.1017/S0373463318000929, 2019. (MAY 2019)

  57. Ratnam, DV, Otsuka, Y,Sivavaraprasad, G, Dabbakuti, JRKK, Development of multivariate ionospheric TEC forecasting algorithm using linear time series model and ARMA over low-latitude GNSS station, ADVANCES IN SPACE RESEARCH, 63, 2848-2856, doi: 10.1016/j.asr.2018.03.024 (May 01, 2019)

  58. Koval, A., Y. Chen, T. Tsugawa, Y. Otsuka, A. Shinbori, M. Nishioka, A. Brazhenko, A. Stanislavsky, A. Konovalenko, Q.-H. Zhang, C. Monstein, and R. Gorgutsa, Direct observations of traveling ionospheric disturbances as focusers of solar radiation: Spectral caustics, Ap. J., 877, doi: 10.3847/1538-4357/ab1b52, 2019.

  59. Shiokawa, K., Y. Otsuka, and M. Connors, Statistical study of auroral/resonant-scattering 427.8-nm emission observed at subauroral latitudes over 14 years, J. Geophys. Res., 124, doi: 10.1029/2019JA026704, 2019.

  60. Yuki Obana, Naomi Maruyama, Atsuki Shinbori, Kumiko K. Hashimoto, Mariangel Fedrizzi, Masahito Nose, Yuichi Otsuka, Nozomu Nishitani, Tomoaki Hori, Atsushi Kumamoto, Fuminori Tsuchiya, Shoya Matsuda, Ayako Matsuoka, Yoshiya Kasahara, Akimasa Yoshikawa, Yoshizumi Miyoshi, and Iku Shinohara (2019) Response of theionosphere‐plasmasphere coupling tothe September 2017 storm: What erodesthe plasmasphere so severely?, SpaceWeather,17, 861-876. https://doi.org/10.1029/2019SW002168 (First published:18 May 2019)

  61. Sergii V. Panasenko, Yuichi Otsuka, Max van de Kamp, Leonid F. Chernogor, Atsuki Shinbori, Takuya Tsugawa, Michi Nishioka, Observation and characterization of traveling ionospheric disturbances induced by solar eclipse of 20 March 2015 using incoherent scatter radars and GPS networks, Journal of Atmospheric and Solar-Terrestrial Physics, 191, 2019,105051,ISSN 1364-6826, https://doi.org/10.1016/j.jastp.2019.05.015 (15 September 2019)

  62. Xu, H., Shiokawa, K., Oyama, S. and Otsuka Y., Thermospheric wind variations observed by a Fabry-Perot interferometer at Tromso, Norway, at substorm onsets, Earth Planets Space 71, 93 (2019). https://doi.org/10.1186/s40623-019-1072-0 (Published: 30 August 2019)

  63. Sarudin, I., Hamid, N. S. A., Abdullah, M., Buhari, S. M., Shiokawa, K., Otsuka, Y., and Yatini, C. Y. (2020), Equatorial Plasma Bubble Zonal Drift Velocity Variations in Response to Season, Local Time, and Solar Activity across Southeast Asia, Journal of Geophysical Research: Space Physics, 125, e2019JA027521. https://doi.org/10.1029/2019JA027521 (First published: 27 February 2020)

  64. Yadav, S., Shiokawa, K., Oyama, S., and Otsuka, Y. (2020), Multievent analysis of oscillatory motion of medium‐scale traveling ionospheric disturbances observed by a 630‐nm airglow imager over Tromso, Journal of Geophysical Research: Space Physics, 125, e2019JA027598. https://doi.org/10.1029/2019JA027598 (First published:21 February 2020)

  65. Sori, T., Shinbori, A., Otsuka, Y.,Tsugawa, T., and Nishioka, M. (2019), Characteristics of GNSS total electroncontent enhancements over themidlatitudes during a geomagneticstorm on 7 and 8 November 2004, Journal of Geophysical Research: SpacePhysics,124,https://doi.org/10.1029/2019JA026713 (First published: 10 October 2019)

  66. Shiokawa, K., Otsuka, Y., and Connors,M. (2019), Statistical study ofauroral/resonant‐scattering 427.8‐nm emission observed at subaurorallatitudes over 14 years.Journal ofGeophysical Research: Space Physics,124, 9293-9301 https://doi.org/10.1029/2019JA026704 (First published:10 October 2019)

  67. Daniel Okoh, Gopi Seemala Babatunde Rabiu John Bosco Habarulema Shuanggen Jin Kazuo Shiokawa Yuichi Otsuka, Malini Aggarwal Jean Uwamahoro Patrick Mungufeni Bolaji Segun Aderonke Obafaye Nada Ellahony Chinelo Okonkwo Mpho Tshisaphungo Dadaso Shetti (2019), A neural network‐based ionospheric model over Africa from Constellation Observing System for Meteorology, Ionosphere, and Climate and Ground Global Positioning System observations Journal of Geophysical Research: Space Physics, 124, 10512-10532 https://doi.org/10.1029/2019JA027065 (First published:09 December 2019)

    Satoshi Tsuchiya Kazuo Shiokawa Hatsuki Fujinami Yuichi Otsuka Takuji Nakamura Martin Connors Ian Schofield, Boris Shevtsov Igor Poddelsky, Three‐Dimensional Fourier Analysis of the Phase Velocity Distributions of Mesospheric and Ionospheric Waves Based on Airglow Images Collected Over 10 Years: Comparison of Magadan, Russia, and Athabasca, Canada, Journal of Geophysical Research: Space Physics, 124, 8110? 8124. https://doi.org/10.1029/2019JA026783 (First published:12 October 2019)

  68. Balan N., Qing-He Zhang, K. Shiokawa, R. Skoug, Zanyang Xing, S. Tulasi Ram and Y. Otsuka, IpsDst of Dst storms applied to ionosphere-thermosphere storms and low latitude aurora, J. Geophys. Res., 124, doi: 10.1029/2019JA027080, 2019. Balan, N., Qing-He Zhang, Zanyang Xing, R. Skoug, K. Shiokawa, H. Luhr, S. Tulasi Ram, Y. Otsuka, and Lingxin Zhao, Capability of Geomagnetic Storm Parameters to Identify Severe Space Weather, Astrophysical Journal, 887:51, https://doi.org/10.3847/1538-4357/ab5113, 2019.

  69. Figueiredo, C. A. O. B., H. Takahashi, C. M. Wrasse, Y. Otsuka, K. Shiokawa, and D. Barros (2018) Medium‐Scale Traveling Ionospheric Disturbances Observed by Detrended Total Electron Content Maps Over Brazil, Journal of Geophysical Research: Space Physics 123(3) 2215-2227 10.1002/2017JA025021
  70. Hisao Takahashi, Cristiano Max Wrasse, Cosme Alexandre Oliveira Barros Figueiredo, Diego Barros, Mangalathayil Ali Abdu, Yuichi Otsuka, Kazuo Shiokawa, Equatorial Plasma Bubble Seeding by MSTIDs in the Ionosphere, Prog Earth Planet Sci 5, 32 (2018). https://doi.org/10.1186/s40645-018-0189-2 (Published on 11 June 2018)

  71. M. Yamamoto, Y. Otsuka, H. Jin, Y. Miyoshi, Relationship between day-to-day variability of equatorial plasma bubble activity from GPS scintillation and atmospheric properties from GAIA assimilation, Progress in Earth and Planetary Science, 2018.
  72. Tsugawa, T., M. Nishioka, M. Ishii1, K. Hozumi, S. Saito, A. Shinbori, Y. Otsuka, A. Saito, S. M. Buhari, M. Abdullah, and P. Supnith, Total Electron Content Observations by Dense Regional and Worldwide International Networks of GNSS, Journal of Disaster Research, Dr13-3-9026, 2018
  73. D.Venkata Ratnam, Yuichi. Otsuka*, G.Sivavaraprasad, and. J R K Kumar Dabbakuti, Development of Multivariate Ionospheric TEC Forecasting Algorithm using Linear Time Series Model and ARMA over Low-latitude GNSS Station, Advances in Space Research 2018
  74. Figueiredo, C. A. O. B., Takahashi, H., Wrasse, C. M., Otsuka, Y., Shiokawa, K., & Barros, D. (2018). Medium‐scale traveling ionospheric disturbances observed by detrended total electron content maps over Brazil. Journal of Geophysical Research: Space Physics, 123, 2215? 2227. https://doi.org/10.1002/2017JA025021 (First published: 05 March 2018)
  75. Shinagawa, H., H. Jin, Y. Miyoshi, H. Fujiwara, T. Yokoyama, and Y.i Otsuka Daily and seasonal variations in the linear growth rate of the Rayleigh-Taylor instability in the ionosphere obtained with GAIA, Progress in Earth and Planetary Science, accepted, 2018.
  76. Li, G., B. Ning, M. A. Abdu, C. Wang, Y. Otsuka, W. Wan, J. Lei, M. Nishioka, T. Tsugawa, L. Hu, G. Yang and C. Yan, Daytime F-region irregularity triggered by rocket-induced ionospheric hole over low latitude, Progress in Earth and Planetary Science, 5:11 https://doi.org/10.1186/s40645-018-0172-y, 2018.
  77. Shiokawa, K., Y. Kato, Y. Hamaguchi, Y. Yamamoto, T. Adachi, M. Ozaki, S.-I. Oyama, M. Nos辿, T. Nagatsuma, Y. Tanaka, Y. Otsuka, Y. Miyoshi, R. Kataoka, Y. Takagi, Y. Takeshita, A. Shinbori, S. Kurita, T. Hori, N. Nishitani, I. Shinohara, F. Tuchiya, Y. Obana, S. Suzuki, N. Takahashi, K. Seki, A. Kadokura, K. Hosokawa, Y. Ogawa, M. Connors, J. M. Ruohoniemi, M. Engebretson, E. Turunen, T. Ulich, J. Manninen, T. Raita, A. Kero, A. Oksanen, M. Back, K. Kauristie, J. Mattanen, D. Baishev, V. Kurkin, A. Oinats, A. Pashinin, R. Vasilyev, R. Rakhmatulin, W. Bristow, and M. Karjala, Ground-based instruments of the PWING project to investigate dynamics of the inner magnetosphere at subauroral latitudes as a part of the ERG-ground coordinated observation network, Earth, Planets and Space, 69:160, doi: 10.1186/s40623-017-0745-9, 2017.
  78. M. Ozaki, K. Shiokawa, Y. Miyoshi, R. Kataoka, M. Connors, T. Inoue, S. Yagitani, Y. Ebihara, C.‐W. Jun, R. Nomura, K. Sakaguchi, Y. Otsuka, H. A. Uchida, I. Schofield, D. W. Danskin (2018), Discovery of 1 Hz range modulation of isolated proton aurora at subauroral latitudes. Geophysical Research Letters, 45. https://doi.org/10.1002/2017GL076486
  79. Okoh, D., Rabiu, B., Shiokawa, K., Otsuka, Y., Segun, B., Falayi, E., Onwuneme, S. & Kaka, R. (2017). First study on the occurrence frequency of equatorial plasma bubbles over West Africa using an all-sky airglow imager and GNSS receivers. Journal of Geophysical Research: Space Physics, 122. https://doi.org/10.1002/2017JA024602 (Accepted manuscript online: 27 November 2017)
  80. Patra, A. K., Pavan Chaitanya, P., St.-Maurice, J.-P., Otsuka, Y., Yokoyama, T., & Yamamoto, M. (2017). The solar flux dependence of ionospheric 150 km radar echoes and implications. Geophys. Res. Lett., 44. https://doi.org/10.1002/2017GL074678 (Accepted article online 13 NOV 2017)
  81. Shinbori, A., Koyama, Y., Nose, M., Hori, T., & Otsuka, Y. (2017). Characteristics of seasonal variation and solar activity dependence of the geomagnetic solar quiet daily variation. Journal of Geophysical Research: Space Physics, 122. https://doi.org/10.1002/2017JA024342 (Version of record online: 28 October 2017)
  82. Pavan Chaitanya, P., A. K. Patra, Y. Otsuka, T. Yokoyama, M. Yamamoto, R. A. Stoneback, and R. A. Heelis (2017), Daytime zonal drifts in the ionospheric 150 km and E regions estimated using EAR observations, J. Geophys. Res. Space Physics, 122, doi:10.1002/2017JA024589. (Accepted article online 16 AUG 2017)
  83. Abadi, P., Y. Otsuka, K. Shiokawa, A. Husin, H. Liu, and S. Saito (2017), Equinoctial asymmetry in the zonal distribution of scintillation as observed by GPS receivers in Indonesia, J. Geophys. Res. Space Physics, 122, doi:10.1002/2017JA024146. (Accepted article online 11 AUG 2017)
  84. Dao, T., Y. Otsuka, K. Shiokawa, M. Nishioka, M. Yamamoto, S. M. Buhari, M. Abdullah, and A. Husin (2017), Coordinated observations of postmidnight irregularities and thermospheric neutral winds and temperatures at low latitudes, J. Geophys. Res. Space Physics, 122, doi:10.1002/2017JA024048. (online published on 4 July 2017)
  85. Takeo, D., K. Shiokawa, H. Fujinami, Y. Otsuka, T. S. Matsuda, M. K. Ejiri, T. Nakamura and M. Yamamoto, Sixteen-year variation of horizontal phase velocity and propagation direction of mesospheric and thermospheric waves in airglow images at Shigaraki, Japan, J. Geophys. Res., 122, doi: 10.0002/2017JA023919, 2017. (Accepted article online 20 JUL 2017)
  86. Nomura, R., K. Shiokawa, Y. Omura, Y. Ebihara, Y. Miyoshi, K. Sakaguchi, Y. Otsuka, and M. Connors (2016), Pulsating proton aurora caused by rising tone Pc1 waves, J. Geophys. Res. Space Physics, 121, 1608?1618, doi:10.1002/2015JA021681.
  87. Buhari, S.M., M. Abdullah, T. Yokoyama, Y. Otsuka, M. Nishioka, A. M. Hasbi, S. A. Bahari, and T. Tsugawa (2017), Climatology of successive equatorial plasma bubbles observed by GPS ROTI over Malaysia, J. Geophys. Res. Space Physics, 122, doi:10.1002/2016JA023202.
  88. Fukushima, D., K. Shiokawa, Y. Otsuka, M. Kubota, T. Yokoyama, M. Nishioka, S. Komonjinda, and C. Yatini, Geomagnetically conjugate observations of ionospheric and thermospheric variations accompanied by a midnight brightness wave at low latitudes, Earth Planets Space, 69:112, doi:10.1186/s40623-017-0698-z, 2017.
  89. Nakamura, Y., K. Shiokawa, Y. Otsuka, S.-I. Oyama, S. Nozawa. T. Komolmis, S. Komonjida, D. Neudegg, C. Yuile, J. Meriwether, H. Shinagawa, and H. Jin, Measurement of thermospheric temperatures using OMTI Fabry-Perot interferometers with 70-mm etalon, Earth, Planets and Space, 69:57, doi: 10.1186/s40623-017-0643-1, 2017.
  90. Figueiredo, C.A., C. Wrasse, H. Takahashi, Y. Otsuka, K. Shiokawa, and D. Silva, Large-scale traveling ionospheric disturbances observed by GPS DTEC maps over north and south America on Saint Patrick's day storm in 2015, J. Geophys. Res., 122, doi: 10.0002/2016JA023417, 2017.
  91. Takahashi, H., C. M. Wrasse, C. M. Denardini, M. B. Padua, E. R. de Paula, S. M. A. Costa, Y. Otsuka, K. Shiokawa, J. F. Galera Monico, A. Ivo and N. Sant'Anna (2016), Ionospheric TEC Weather Map Over South America, Space Weather, 14, 937-949, doi:10.1002/2016SW001474. (online: 11 NOV 2016)
  92. Ajith, K. K., S. Tulasi Ram, M. Yamamoto, Y. Otsuka, and K. Niranjan (2016), On the fresh development of equatorial plasma bubbles around the midnight hours of June solstice, J. Geophys. Res. Space Physics, 121, doi:10.1002/2016JA023024. (Published on line 17 September 2016)
  93. Nishino M. N., K. Shiokawa, and Y. Otsuka, The first long-term all-sky imager observation of lunar sodium tail, Icarus, 280, 199-204, 2016. (Published online 4 August 2016)
  94. Ozaki, M., K. Shiokawa, Y. Miyoshi, R. Kataoka, S. Yagitani, T. Inoue, Y. Ebihara, C.-W Jun, R. Nomura, K. Sakaguchi, Y. Otsuka, M. Shoji, I. Schofield, M. Connors, and V. K. Jordanova, Fast modulations of pulsating proton aurora related to subpacket structures of Pc1 geomagnetic pulsations at subauroral latitudes, Geophys. Res. Lett., 43, doi:10.1002/2016GL070008. (online 29 JUL 2016)
  95. Dao, T., Y. Otsuka, K. Shiokawa, S. Tulasi Ram, and M. Y amamoto (2016), Altitude development ofpostmidnight F region Field-alignedirregular ities observed using Equatorial Atmosphere Radar inIndonesia, Geophys.Res.Lett., 43,1015-1022, doi:10.1002/2015GL067432. (Published online 13 FEB 2016)
  96. Li, G., Y. Otsuka, B. Ning, M. A. Abdu, M. Yamamoto, W. Wan, L. Liu, and P. Abadi (2016), Enhanced ionospheric plasma bubble generation in more active ITCZ, Geophys. Res. Lett., 43, 2389-2395, doi:10.1002/2016GL068145. (Published online 24 MAR 2016)
  97. Nomura, R., K. Shiokawa, Y. Omura, Y. Ebihara, Y. Miyoshi, K. Sakaguchi, Y. Otsuka,M. Connors (2016), Pulsating proton aurora caused by rising tone Pc1 waves, J. Geophys. Res., DOI: 10.1002/2015JA021681, Accepted manuscript online: 9 JAN 2016
  98. Tulasi Ram, T. Yokoyama, Y. Otsuka, K. Shiokawa, S. Sripathi1, B. Veenadhari, R. Heelis, K. K. Ajith, V. S. Gowtam, S. Gurubaran, P. Supnithi, and M. Le Huy (2015), Duskside enhancement of equatorial zonal electric field response to convection electric fields during the St. Patrick’s Day storm on 17 March 2015, J. Geophys. Res. Space Physics, 120, doi:10.1002/2015JA021932.
  99. Ozaki, M., S. Yagitani, K. Sawai, K. Shiokawa, Y. Miyoshi, R. Kataoka, A. Ieda, Y. Ebihara, M. Connors, I. Schofield, Y. Katoh, Y. Otsuka, N. Sunagawa, and V. K. Jordanova (2015), A direct link between chorus emissions and pulsating aurora on timescales from milliseconds to minutes: A case study at subauroral latitudes,J. Geophys. Res. Space Physics, 120, doi:10.1002/2015JA021381. (Published online 27 NOV 2015)
  100. Abadi, P., Y. Otsuka, and Takuya Tsugawa, Effects of pre-reversal enhancement of ExB drift on the latitudinal extension of plasma bubble in Southeast Asia, Earth, Planets and Space, 67--74, DOI 10.1186/s40623-015-0246-7, 2015
  101. Perwitasari, S., T. Sakanoi, A. Yamazaki, Y. Otsuka, Y. Hozumi, Y. Akiya, A. Saito, K. Shiokawa, and S. Kawamura (2015), Coordinated airglow observations between IMAP/VISI and a ground-based all-sky imager on concentric gravity wave in the mesopause, J. Geophys. Res. Space Physics, 120, 9706?9721, doi:10.1002/2015JA021424. (Published online 3 NOV 2015)
  102. Thomas, E. G., K. Hosokawa, J. Sakai, J. Baker, J. Ruohoniemi, S. Taguchi, K. Shiokawa, Y. Otsuka, A. J. Coster, J.-P. St.-Maurice, and K. A. McWilliams, Multi-instrument, high-resolutionimaging of polar cap p atch trans-portation, Radio Sci., 50, 904?915,doi:10.1002/2015RS005672.
  103. Ishida, T., Y. Ogawa, A. Kadokura, K. Hosokawa, and Y. Otsuka, Direct observations of blob deformation during a substorm, Ann. Geophys., 33, 525-530, doi:10.5194/angeo-33-525-2015, 2015. (Article first published online: 25 SEP 2015)
  104. Hashimoto, A., K. Shiokawa, Y. Otsuka, S.-i. Oyama, S. Nozawa, T. Hori, M. Lester, and M. G. Johnsen (2015), Statistical study of auroral fragmentation into patches, J. Geophys. Res. Space Physics, 120, 6207?6217, doi:10.1002/2015JA021000. (Version of Record online: 10 AUG 2015)
  105. Takahashi H., C.. M. Wrasse, Y. Otsuka, A. Ivo, V. Gomes, I. Paulino, A. F. Medeiros, C. M. Denardini, N. Sant'Anna, and K. Shiokawa, Plasma bubble monitoring by TEC map and 630 nm airglow image, J. Atmos. Solar-Terr. Phys., vol.130-131, p.151-158, doi:10.1016/j.jastp.2015.06.003, 2015. (Available online 11 June 2015)
  106. Ishida, T., Y. Ogawa, A. Kadokura, K. Hosokawa, and Y. Otsuka, Direct observations of blob deformation during a substorm, Ann. Geophys., 33, 525-530, doi:10.5194/angeo-33-525-2015, 2015.
  107. Hori, T., Y. Miyashita, Y. Miyoshi, K. Seki, T. Segawa, Y.-M. Tanaka, K. Keika, M. Shoji, I. Shinohara, K. Shiokawa, Y. Otsuka, S. Abe, A. Yoshikawa, K. Yumoto, Y. Obana, N. Nishitani, A. S. Yukimatu, T. Nagatsuma, M. Kunitake, K. Hosokawa, Y. Ogawa, K. T. Murata, M. Nose, H. Kawano, and T. Sakanoi, CDF data archive and integrated data analysis platform for ERG-related ground data developed by ERG Science Center (ERG-SC), J. Space Sci. Info. Jpn., vol. 4, JAXA-RR-14-009 (ISSN 1349-1113), 75-89, 2015.
  108. Fukushima, D., K. Shiokawa, Y. Otsuka, M. Nishioka, M. Kubota, T. Tsugawa, T. Nagatsuma, S. Komonjinda, and C. Y. Yatini (2015), Geomagnetically conjugate observation of plasma bubbles and thermospheric neutral winds at low latitudes, J. Geophys. Res. Space Physics, 120, doi:10.1002/2014JA020398. (Published online 16 MAR 2015)
  109. Ajith, K. K., S. T. Ram, M. Yamamoto, T. Yokoyama, V. S. Gowtam, Y. Otsuka, T. Tsugawa, and K. Niranjan (2015), Explicit characteristics of evolutionary-type plasma bubbles observed from Equatorial Atmosphere Radar during the low to moderate solar activity years 2010?2012, J. Geophys. Res. Space Physics, 120, 1371?1382, doi:10.1002/2014JA020878. (Accepted 7 JAN 2015, Accepted article online 11 JAN 2015, Published online 5 FEB 2015)
  110. Shiokawa, K., Y. Otsuka, K.J.W. Lynn, P. Wilkinson, and T. Tsugawa (2015), Airglow-imaging observation of plasma bubble disappearance at geomagnetically conjugate points, Earth, Planets and Space, 67, 43, doi: 10.1186/s40623-015-0202-6 (Accepted: 3 February 2015, Published: 26 March 2015)
  111. Shinbori, A., Y. Koyama, M. Nose, T. Hori, Y. Otsuka, and A. Yatagai (2014), Long-term variation in the upper atmosphere as seen in the geomagnetic solar quiet daily variation, Earth, Planets and Space 2014, 66:155 doi:10.1186/s40623-014-0155-1. (Accepted: 11 November 2014, Published: 11 December 2014)
  112. Buhari, S. M., M. Abdullah, A. M. Hasbi, Y. Otsuka, T. Yokoyama, M. Nishioka, and T. Tsugawa (2014), Continuous generation and two-dimensional structure of equatorial plasma bubbles observed by high-density GPS receivers in Southeast Asia, J. Geophys. Res. Space Physics, 119, doi:10.1002/2014JA020433. (Accepted 30 NOV 2014, Accepted article online 3 DEC 2014)
  113. Balan, N., R. Skoug, S. Tulasi Ram, P. K. Rajesh, K. Shiokawa, Y. Otsuka, I. S. Batista, Y. Ebihara, and T. Nakamura (2014), CME front and severe space weather, J. Geophys. Res. Space Physics, 119, doi:10.1002/2014JA020151. (Accepted 22 NOV 2014, Accepted article online 26 NOV 2014)
  114. Narayanan, V. L., K. Shiokawa, Y. Otsuka, and S. Saito (2014), Airglow observations of nighttime medium-scale traveling ionospheric disturbances from Yonaguni: Statistical characteristics and low-latitude limit, J. Geophys. Res. Space Physics, 119, 9268?9282, doi:10.1002/2014JA020368. (Issue published online: 23 DEC 2014; Article first published online: 28 NOV 2014; Accepted manuscript online: 3 NOV 2014 04:39AM EST)
  115. Shiokawa, K., A. Hashimoto, T. Hori, K. Sakaguchi, Y. Ogawa, E. Donovan, E. Spanswick, M. Connors, Y. Otsuka, S.-I. Oyama, S. Nozawa, K. McWilliams (2014), Auroral fragmentation into patches, J. Geophys. Res. Space Physics, 119, 8249?8261, doi:10.1002/2014JA020050. (First published: 21 October 2014)
  116. Hosokawa, K., Y. Otsuka, Y. Ogawa and T. Tsugawa (2014), Observations of GPS scintillation during an isolated auroral substorm, Progress in Earth and Planetary Science, 1:16, doi:10.1186/2197-4284-1-16 (Published: 4 August 2014)

  117. Patra, A. K., P. P. Chaitanya, Y. Otsuka, T. Yokoyama, M. Yamamoto, R. A. Stoneback, and R. A. Heelis (2014), Vertical ExB drifts from radar and C/NOFS observations in the Indian and Indonesian sectors: Consistency of observations and model, J. Geophys. Res. Space Physics, 119, 3777-3788, doi:10.1002/2013JA019732. (published online on 6 MAY 2014)

  118. Takahashi, H., S. Costa, Y. Otsuka, K. Shiokawa, J. F. G. Monico, E. Paula, P. Nogueira , C. M. Denardini, F. Becker-Guedes, C. M. Wrasse, A. S. Ivo, V. C. F. Gomes, W. Gargarela Jr., N. Sant'Anna, and R. Gatto (2014), Diagnostics of equatorial and low latitude ionosphere by TEC mapping over Brazil, Adv. Space Res., 54, 385-394, 10.1016/j.asr.2014.01.032 (available online 6 February 2014).

  119. Hosokawa, K., S. Taguchi, K. Shiokawa, Y. Otsuka, Y. Ogawa, and M. Nicolls (2014), Global imaging of polar cap patches with dual airglow imagers, Geophys. Res. Lett., 41, 1-6, doi:10.1002/2013GL058748. (Article first published online: 14 JAN 2014)

  120. Suzuki, S., S. L. Vadas, K. Shiokawa, Y. Otsuka, S. Kawamura, and Y. Murayama (2013), Typhoon-induced concentric airglow structures in the mesopause region, Geophys. Res. Lett., 40, 5983?5987, doi:10.1002/2013GL058087. (Article first published online: 19 NOV 2013)

  121. Shinagawa, H., T. Tsugawa, M. Matsumura, T. Iyemori, A. Saito, T. Maruyama, H. Jin, M. Nishioka and Y. Otsuka, Two-dimensional simulation of ionospheric variations in the vicinity of the epicenter of the Tohoku-oki earthquake on 11 March 2011, Geophys. Res. Lett., doi: 10.1002/2013GL057627. (Accepted 4 OCT 2013)

  122. Li, G., B. Ning, M. A. Abdu, Y. Otsuka, T. Yokoyama, M. Yamamoto, and L. Liu (2013), Longitudinal characteristics of spread F backscatter plumes observed with the EAR and Sanya VHF radar in Southeast Asia, J. Geophys. Res. Space Physics, 118, doi:10.1002/jgra.50581. (accepted 17 September 2013)

  123. Nishioka, M., T. Maruyama, Y. Otsuka, T. Tsugawa, H. Ishibashi, K. Shiokawa, and M. Ishii, Comparison of meridional thermospheric winds observed by ionosondes and Fabry-Perot iterferometers (in Japanese), Antarctic Record, 57(3), 357-368, 2013. (西岡未知、丸山隆、大塚雄一、津川卓也、石橋弘光、塩川和夫、石井守、 イオノゾンデおよびファブリ・ペロー干渉計によって観測された子午面熱圏風の比較、 南極資料, 57(3), 369-378, 2013)

  124. Balan, N., Y. Otsuka, M. Nishioka, J. Y. Liu, and G. J. Bailey (2013), Physical mechanisms of the ionospheric storms at equatorial and higher latitudes during the recovery phase of geomagnetic storms, J. Geophys. Res. Space Physics, 118, 2660.2669, doi:10.1002/jgra.50275. (published 23 May 2013.)

  125. Lynn, K. J. W., Y. Otsuka, and K. Shiokawa (2003), Ionogram-based range-time displays for observing relationships between ionosonde satellite traces, spread F and drifting optical plasma depletions, J. Atmos. Solar-Terr. Phys., 98, 105-112. (Available online 3 April 2013)

  126. Suzuki, S., K. Shiokawa, Y. Otsuka, S. Kawamura, and Y. Murayama (2013), Evidence of gravity wave ducting in the mesopause region from airglow network observations, Geophys. Res. Lett., 40, 601-605, doi:10.1029/2012GL054605. (published 14 February 2013)

  127. Shiokawa, K., M. Mori, Y. Otsuka, S. Oyama, S. Nozawa, S. Suzuki, and M. Connors, Observation of nighttime medium-scale travelling ionospheric disturbances by two 630-nm airglow imagers near the auroral zone, J. Atmos. Solar-Terr. Phys., 103, 184-194, 2013.

  128. Patra, A. K., Chaitanya, P. Pavan; Mizutani, N., Otsuka, Y., Yokoyama, T., and Yamamoto, M., A comparative study of equatorial daytime vertical E x B drift in the Indian and Indonesian sectors based on 150 km echoes, J. Geophys. Res., 117, A11312, DOI: 10.1029/2012JA018053, 2012. (NOV 15 2012)

  129. Kutiev, I, Otsuka, Y., Pancheva, D. Heelis, R. (2012), Response of low-latitude ionosphere to medium-term changes of solar and geomagnetic activity, J. Geophys. Res., 117, A08330, doi:10.1029/2012JA017641 (AUG 28 2012)

  130. Fukushima, D., K. Shiokawa, Y. Otsuka, and T. Ogawa (2012), Observation of equatorial nighttime medium-scale traveling ionospheric disturbances in 630-nm airglow images over 7 years, J. Geophys. Res., 117, A10324, doi:10.1029/2012JA017758. (published 24 October 2012).

  131. Shiokawa, K., M. Mori, Y. Otsuka, S. Oyama, and S. Nozawa, Motion of high-latitude nighttime medium-scale traveling ionospheric disturbances associated with auroral brightening, J. Geophys. Res., 117, A10316, doi.10.1029/2012JA017928, 2012. (published 12 October 2012).

  132. Nishioka, M., Y. Otsuka, K. Shiokawa, T. Tsugawa, Effendy, P. Supnithi, T. Nagatsuma, and K. T. Murata (2012), On post-midnight field-aligned irregularities observed with a 30.8-MHz radar at a low latitude: Comparison with F-layer altitude near the geomagnetic equator, J. Geophys. Res., 117, A08337, doi:10.1029/2012JA017692. (published 31 August 2012)

  133. Shiokawa, K., Y. Otsuka, S. Oyama, S. Nozawa, M. Satoh, Y. Katoh, Y. Hamaguchi, Y. Yamamoto and J. Meriwether, Development of low-cost sky-scanning Fabry-Perot interferometers for airglow and auroral studies, Earth Planets Space, vol.64, no.11, 1033-1046, 2012 (Online published November 26, 2012).

  134. Jayachandran, P. T., K. Hosokawa, K. Shiokawa, Y. Otsuka, C. Watson, S. C. Mushini, J. W. MacDougall, P. Prikryl, R. Chadwick, and T. D. Kelly (2012), GPS total electron content variations associated with poleward moving Sun-aligned arcs, J. Geophys. Res., 117, A05310, doi:10.1029/2011JA017423 (published 9 May 2012).

  135. Nomura, R., K. Shiokawa, K. Sakaguchi, Y. Otsuka, and M. Connors (2012), Polarization of Pc1/EMIC waves and related proton auroras observed at subauroral latitudes, J. Geophys. Res., 117, A02318, doi:10.1029/2011JA017241. (published 29 February 2012)

  136. Balan, N., J. Y. Liu, Y. Otsuka, S. Tulasi Ram, and H. Luhr (2012), Ionospheric and thermospheric storms at equatorial latitudes observed by CHAMP, ROCSAT, and DMSP, J. Geophys. Res., 117, A01313, doi:10.1029/2011JA016903. (published 20 January 2012)

  137. Lynn, K. J. W., Y. Otsuka, and K. Shiokawa (2011), Simultaneous observations at Darwin of equatorial bubbles by ionosonde-based range/time displays and airglow imaging, Geophys. Res. Lett., 38, L23101, doi:10.1029/2011GL049856. (published 7 December 2011)

  138. Yokoyama, T., M. Yamamoto, Y. Otsuka, M. Nishioka, T. Tsugawa, S. Watanabe, and R. F. Pfaff (2011), On post-midnight low-latitude ionospheric irregularities during solar minimum: 1. Equatorial Atmosphere Radar and GPS-TEC observations in Indonesia, J. Geophys. Res., 116, A11325, doi:10.1029/2011JA016797. (published 22 November 2011)

  139. Yokoyama, T., R. F. Pfaff, P. Roddy, M. Yamamoto, and Y. Otsuka (2011), On post-midnight low-latitude ionospheric irregularities during solar minimum: 2. C/NOFS observations and comparisons with the Equatorial Atmosphere Radar, J. Geophys. Res., 116, A11326, doi:10.1029/2011JA016798. (published 22 November 2011)

  140. Makela, J., and Y. Otsuka (2011), Overview of Nighttime Ionospheric Instabilities at Low- and Mid-Latitudes: Coupling Aspects Resulting in Structuring at the Mesoscale, Space Sci. Rev., DOI 10.1007/s11214-011-9816-6. (published online: 27 August 2011)

  141. M. Matsumura, A. Saito, T. Iyemori, H. Shinagawa, T. Tsugawa, Y. Otsuka, M. Nishioka, and C. H. Chen, Numerical simulations of atmospheric waves excited by the 2011 off the Pacific coast of Tohoku Earthquake, 2011, Earth Planets Space, 2011. (Accpted July 23, 2011)

  142. T. Tsugawa, A. Saito, Y. Otsuka, M. Nishioka, T. Maruyama, H. Kato, T. Nagatsuma, and K. T. Murata, Ionospheric disturbances detected by GPS total electron content observation after the 2011 Tohoku Earthquake, Earth Planets Space, 2011. (Online published September 27, 2011)

  143. A. Saito, T. Tsugawa, Y. Otsuka, M. Nishioka, T. Iyemori, M. Matsumura, S. Saito, C. H. Chen, Y. Goi, and N. Choosakul, Acoustic resonance and plasma depletion detected by GPS total electron content observation after the 2011 Tohoku Earthquake, Earth Planets Space, 2011. (Online published September 27, 2011)

  144. C. H. Chen, A. Saito, C. H. Lin, J. Y. Liu, H. F. Tsai, T. Tsugawa, Y. Otsuka, M. Nishioka, and M. Matsumura, Long-distance propagation of ionospheric disturbance generated by the 2011 Tohoku Earthquake, Earth Planets Space, 2011. (Accepted June 16, 2011)

  145. Takashi Maruyama, Takuya Tsugawa, Hisao Kato, Akinori Saito, Yuichi Otsuka, and Michi Nishioka, Ionospheric multiple stratifications and irregularities induced by the 2011 Tohoku earthquake, Earth Planets Space, 2011. (Accepted June 7, 2011)

  146. Nozomu Nishitani, Tadahiko Ogawa, Yuichi Otsuka, Keisuke Hosokawa, and Tomoaki Hori, Propagation of large amplitude ionospheric disturbances with velocity dispersion observed by the SuperDARN Hokkaido radar after the 2011 off the Pacific coast of Tohoku Earthquake, Earth Planets Space, 2011. (Accepted July 8, 2011).

  147. Liu, H., M. Yamamoto, S. T. Ram, T. Tsugawa, Y. Otsuka, C. Stolle, E. Doornbos, K. Yumoto, and T. Nagatsuma, Equatorial Electrodynamics and Neutral Background in the Asian Sector During the 2009 Stratospheric Sudden Warming, J. Geophys. Res., 116, A08308, doi:10.1029/2011JA016607, 2011. (published 8 July 2011)

  148. Balan, N., M. Yamamoto, J. Y. Liu, Y. Otsuka, H. Liu, and H. Luhr, New aspects of thermospheric and ionospheric storms revealed by CHAMP, J. Geophys. Res., 116, A07305, doi:10.1029/2010JA016399, 2011. (published 8 July 2011)

  149. Hosokawa, K., J. I. Moen, K. Shiokawa, and Y. Otsuka (2011), Decay of polar cap patch, J. Geophys. Res., 116, A05306, doi:10.1029/2010JA016297. (published 10 May 2011)

  150. Adachi, T., Y. Otsuka, M. Yamaoka, M. Yamamoto, K. Shiokawa, A. B. Chen, and R.-R. Hsu, First satellite-imaging observation of medium-scale traveling ionospheric disturbances by FORMOSAT-2/ISUAL, Geophys. Res. Lett., 38, L04101, doi:10.1029/2010GL046268, 2011. (published 16 February 2011)

  151. Balan, N., M. Yamamoto, V. Sreeja, I. S. Batista, K. J. W. Lynn, M. A. Abdu, S. Ravindran, T. Kikuchi, Y. Otsuka, K. Shokawa, and S. Alex, A statistical study of the response of the dayside equatorial F2 layer to the main phase of intense geomagnetic storms as an indicator of penetration electric eld, J. Geophys. Res., 116, A03323, doi:10.1029/2010JA016001, 2011. (published 24 March 2011)

  152. Jin, H., Y. Miyoshi, H. Fujiwara, H. Shinagawa, K. Terada, N. Terada, M. Ishii, Y. Otsuka, and A. Saito, Vertical connection from the tropospheric activities to the ionospheric longitudinal structure simulated by a new Earth’s whole atmosphere‐ionosphere coupled model, J. Geophys. Res., 116, A01316, doi:10.1029/2010JA015925. (published 27 January 2011)

  153. Hosokawa, K., J. I. Moen, K. Shiokawa, and Y. Otsuka, Motion of polar cap arcs, J. Geophys. Res., 116, A01305, doi:10.1029/2010JA015906. (published 15 January 2011)

  154. Oyama, S., Shiokawa, K., Kurihara, J., Tsuda, T. T., Nozawa, S., Ogawa, Y., Otsuka, Y., and Watkins, B. J., Lower-thermospheric wind fluctuations measured with an FPI during pulsating aurora at Tromso, Norway, Ann. Geophys., 28, 1847-1857, doi:10.5194/angeo-28-1847-2010, 2010.

  155. Hosokawa, K., T. Tsugawa, K. Shiokawa, Y. Otsuka, N. Nishitani, T. Ogawa, and M. R. Hairston (2010), Dynamic temporal evolution of polar cap tongue of ionization during magnetic storm, J. Geophys. Res., 115, A12333, doi:10.1029/2010JA015848. (published 24 December 2010)

  156. Adachi, T., M. Yamaoka, M. Yamamoto, Y. Otsuka, H. Liu, C.‐C. Hsiao, A. B. Chen, and R.‐R. Hsu, Midnight latitude‐altitude distribution of 630 nm airglow in the Asian sector measured with FORMOSAT‐2/ISUAL, J. Geophys. Res., 115, A09315, doi:10.1029/2009JA015147. (published 18 September 2010)

  157. Shiokawa, K., R. Nomura, K. Sakaguchi, Y. Otsuka, Y. Hamaguchi, M. Satoh, Y. Katoh, Y. Yamamoto, B. M. Shevtsov, S. Smirnov, I. Poddelsky, and M. Connors (2010), The STEL induction magnetometer network for observation of high-frequency geomagnetic pulsations, Earth Planets Space, 62 (No. 6), 517-524, doi:10.5047/eps.2010.05.003. (Online published August 6, 2010)

  158. Hayashi, H., N. Nishitani, T. Ogawa, Y. Otsuka, T. Tsugawa, K. Hosokawa, and A. Saito (2010), Large-Scale Traveling Ionospheric Disturbance Observed by SuperDARN Hokkaido HF Radar and GPS Networks on 15 December 2006, J. Geophys. Res., doi:10.1029/2009JA014297, 2010. (published 16 June 2010)

  159. Thampi, S. V., M. Yamamoto, H. Liu, S. Saito, Y. Otsuka, and A. K. Patra (2010), Nighttime-like Quasi Periodic echoes induced by a partial solar eclipse, Geophys. Res. Lett., doi:10.1029/2010GL042855, 2010. doi:10.1029/2010GL042855 (published 14 May 2010)

  160. Li, G., B. Ning, L. Hu, L. Liu, X. Yue, W. Wan, B. Zhao, K. Igarashi, M. Kubota, Y. Otsuka, J. S. Xu, J. Y. Liu, and J. L. Chau (2009), Longitudinal development of low-latitude ionospheric irregularities during the geomagnetic storms of July 2004, J. Geophys. Res., doi:10.1029/2009JA014830, 2010. (published 1 April 2010)

  161. N. Balan, K. Shiokawa, Y. Otsuka, T. Kikuchi, D. Vijaya Lekshmi, S. Kawamura, M. Yamamoto, and G. J. Bailey (2010), A physical mechanism of positive ionospheric storms at low latitudes and midlatitudes, J. Geophys. Res., 115, A02304, doi:10.1029/2009JA014515. (published 3 February 2010)

  162. Hosokawa, K., J.-P. St.-Maurice, G. J. Sofko, K. Shiokawa, Y. Otsuka, and T. Ogawa (2010), Reorganization of polar cap patches through shears in the background plasma convection, J. Geophys. Res., doi:10.1029/2009JA014599, (published 8 January 2010)

  163. Sahai, Y., F. Becker-Guedes, P. R. Fagundes, A. J. de Abreu, R. de Jesus, V. G. Pillat, J. R. Abalde, C. R. Martinis, C. Brunini, M. Gende, C.-S. Huang, X. Pi, W. L. C. Lima, J. A. Bittencourt, and Y. Otsuka (2009), Observations of the F-region ionospheric irregularities in the South American sector during the October 2003 "Halloween Storms", Ann. Geophys., 27, 4463-4477. (published 8 December, 2009)

  164. Thampi, S. V., M. Yamamoto, R. T. Tsunoda, Y. Otsuka, T. Tsugawa, J. Uemoto, and M. Ishii (2009), First observations of large-scale wave structure and equatorial spread F using CERTO radio beacon on the C/NOFS satellite, Geophys. Res. Lett., 36, L18111, doi:10.1029/2009GL039887. (published 26 September 2009)

  165. Hasbi, A. M., M. Momani, M. Ali, N. Misran, K. Shiokawa, Y. Otsuka, and K. Yumoto, Ionospheric and geomagnetic disturbances during the 2005 Sumatran earthquakes. Journal of Atmospheric and Solar-Terrestrial Physics, 71, 17-81, doi:10.1016/j.jastp.2009.09.004, 1992-2005, 2009 (December 2009)

  166. Shalimov, S., T. Ogawa, Y.Otsuka, On the gravitywave-driven instability o fE layer at mid-latitude, J. Atmos. Solar-Terr. Phys., 71, 1943-1947, 2009. (available online 29 August 2009)

  167. Suzuki, S., K. Hosokawa, T. Shibata, K. Shiokawa, Y. Otsuka, N. Nishitani, T. Ogawa , A. Koustov, B. Shevtsov (2009), Coordinated observations of nighttime medium-scale traveling ionospheric disturbances in 630-nm airglow and HF radar echoes at midlatitudes, J. Geophys. Res., 114, A7, A07312, doi:0.1029/2008JA013963 (published on 25 July 2009)

  168. Shiokawa, K., K. Hosokawa, K. Sakaguchi, A. Ieda, Y. Otsuka, T. Ogawa and M. Connors, The Optical Mesosphere Thermosphere Imagers (OMTIs) for network measurements of aurora and airglow, Future Perspectives of Space Plasma and Particle Instrumentation and International Collaborations, AIP Conference proceedings, edited by M. Hirahara, Y. Miyoshi, N. Terada, I. Shinohara, and T. Mukai, AIP Conference proceedings, pp.212-215, doi:10.1063/1.3169292, 2009. (published on June 2009)

  169. Onishi, T., T. Tsugawa, Y. Otsuka, J.-J. Berthelier, and J.-P. Lebreton (2009), First simultaneous observations of daytime MSTIDs over North America using GPS-TEC and DEMETER satellite data, Geophys. Res. Lett., 36, L11808, doi:10.1029/ 2009GL038156 (published 5 June 2009).

  170. Balan, N., H. Alleyne, Y. Otsuka, D. Vijaya Lekshmi, B. G. Fejer, and I. McCrea, Relative effects of electric field and neutral wind on positive ionospheric storms, Earth Planets Space, 61, 439-445, 2009. (Online published May 14, 2009)

  171. Ogawa, T., Y. Miyoshi, Y. Otsuka, T. Nakamura, and K. Shiokawa, Equatorial GPS ionospheric scintillations over Kototabang, Indonesia and their relation to atmospheric waves from below, Earth Planets Space, 61, 397-410, 2009.(Online published May 14, 2009)

  172. Shiokawa, K., Y. Otsuka, and T. Ogawa, Propagation characteristics of nighttime mesospheric and thermospheric waves observed by optical mesosphere thermosphere imagers at middle and low latitudes, Earth, Planets, Space, 61, 479-491, 2009. (Online published May 14, 2009)

  173. Hosokawa, K., T. Kashimoto, S. Suzuki, K. Shiokawa, Y. Otsuka, and T. Ogawa (2009), Motion of polar cap patches: A statistical study with all-sky airglow imager at Resolute Bay, Canada, J. Geophys. Res., 114, A04318, doi:10.1029/2008JA014020. (published 25 April 2009.)

  174. Hosokawa, K., T. Tsugawa, K. Shiokawa, Y. Otsuka, T. Ogawa, and M. R. Hairston (2009), Unusually elongated, bright airglow plume in the polar cap F region: is it tongue of ionization?,Geophys. Res. Lett., 36, L07103, doi:10.1029/2009GL037512. (published 7 April 2009.)

  175. Suzuki, S., K. Shiokawa, A. Z. Liu, Y. Otsuka, T. Ogawa, and T. Nakamura (2009), Characteristics of equatorial gravity waves derived from mesospheric airglow imaging observations, Ann. Geophys., 27, 1625--1629. (published on 06 Apr 2009)

  176. Ogawa, T., N. Nishitani, Y. Otsuka, K. Shiokawa, T. Tsugawa, and K. Hosokawa (2009), Medium-scale traveling ionospheric disturbances observed with the SuperDARN Hokkaido radar, all-sky imager and GPS network, and their relation to concurrent sporadic-E irregularities, J. Geophys. Res., 114, A03316, doi:10.1029/2008JA013893. (published 31 March 2009)

  177. Balan, N., K. Shiokawa, Y. Otsuka, S. Watanabe, and G. J. Bailey (2009), Super plasma fountain and equatorial ionization anomaly during penetration electric field, J. Geophys. Res., 114, A03310, doi:10.1029/2008JA013768. (published 21 March 2009.)

  178. Hosokawa, K., K. Shiokawa, Y. Otsuka, T. Ogawa, J.-P. St-Maurice, G. J. Sofko, and D. A. Andre (2009), Relationship between polar cap patches and field-aligned irregularities as observed with an all-sky airglow imager at Resolute Bay and the PolarDARN radar at Rankin Inlet, J. Geophys. Res., 114, A03306, doi:10.1029/2008JA013707. (published 19 March 2009.)

  179. Yokoyama, T., D. L. Hysell, Y. Otsuka, and M. Yamamoto (2009), Three-dimensional simulation of the coupled Perkins and Es-layer instabilities in the nighttime midlatitude ionosphere, J. Geophys. Res., 114, A03308, doi:10.1029/2008JA013789. (published 19 March 2009)

  180. Yokoyama, T., D. L. Hysell, A. K. Patra, Y. Otsuka, and M. Yamamoto, Zonal asymmetry of daytime 150-km echoes observed by Equatorial Atmosphere Radar in Indonesia, Ann. Geophys., 27, 967-974, 2009. (published 2 March 2009)
  181. Ogawa, T. Y. Otsuka, K. Shiokawa, T. Tsugawa, A. Saito, K. Hoshinoo, K. Matunaga, M. Kubota, and M. Ishii, Medium-scale traveling ionospheric disturbances and plasma bubbles observed by an all-sky airglow imager at Yonaguni, Japan, Terr. Atmos. Ocean Sci., 20, 287-295, doi:10.3319/TAO.2007.12.06.02(F3C), 2009. (Feb 2009)

  182. Sahai, Y., F. Becker-Guedes, P. Fagundes, R. de Jesus, A. de Abreu, Y. Otsuka, K. Shiokawa, K. Igarashi, K. Yumoto, Chao-Song Huang, H. Lan, A. Saito, F. Luis Guarnieri, V. Pillat, J. Bittencourt (2009), Effects observed in the ionospheric F region in the east Asian sector during the intense geomagnetic disturbances in the early part of November 2004, J. Geophys. Res., doi:10.1029/2008JA013053. (published 7 January 2009)

  183. Shiokawa, K., T. Tsugawa, Y. Otsuka, T. Ogawa, G. Lu, A. Saito, and M. Yamamoto, Optical and radio observations and AMIE/TIEGCM modeling of nighttime traveling ionospheric disturbances at mid-latitudes during geomagnetic storms, AGU monograph on Mid-Latitude Ionospheric Dynamics and Disturbances, 271-281, 2008.

  184. Lee, C. C., Y. A. Liou, Y. Otsuka, F. D. Chu, T. K. Yeh, K. Hoshinoo, and K. Matunaga, Nighttime medium-scale traveling ionospheric disturbances detected by network GPS receivers in Taiwan, J. Geophys. Res., 113, A12316, doi:10.1029/2008JA013250, 2008. (published 31 December 2008)

  185. Shiokawa, K., Y. Otsuka, N. Nishitani, T. Ogawa, T. Tsugawa, T. Maruyama, S. E. Smirnov, V. V. Bychkov, and B. M. Shevtsov (2008), Northeastward motion of nighttime medium-scale traveling ionospheric disturbances at middle latitudes observed by an airglow imager, J. Geophys. Res., 113, A12312, doi:10.1029/2008JA013417. (published 30 December 2008)

  186. Saito, S., S. Fukao, M. Yamamoto, Y. Otsuka, and T. Maruyama (2008), Decay of 3-m-scale ionospheric irregularities associated with a plasma bubble observed with the Equatorial Atmosphere Radar, J. Geophys. Res., 113, A11318, doi:10.1029/2008JA013118. (published 25 November 2008)

  187. Balan, N., S. V. Thampi, K. Lynn, Y. Otsuka, H. Alleyne, S. Watanabe, M. A. Abdu, and B. G. Fejer (2008), F3 layer during penetration electric field, J. Geophys. Res., 113, A00A07, doi:10.1029/2008JA013206. (published 4 September 2008)

  188. Sakaguchi, K., K. Shiokawa, Y. Miyoshi, Y. Otsuka, T. Ogawa, K. Asamura, and M. Connors (2008), Simultaneous appearance of isolated auroral arcs and Pc 1 geomagnetic pulsations at subauroral latitudes, J. Geophys. Res., 113, A05201, doi:10.1029/2007JA012888. (published 2 May 2008)

  189. Patra A. K., T. Yokoyama, Y. Otsuka, M. Yamamoto (2008), Daytime 150-km echoes observed with the Equatorial Atmosphere Radar in Indonesia: First results, Geophys. Res. Lett., 35, L06101, doi:10.1029/2007GL033130. (published 19 March 2008)

  190. Yokoyama,T., Y. Otsuka, T. Ogawa, M. Yamamoto, and D. L. Hysell, First three-dimensional simulation of the Perkins instability in the nighttime midlatitude ionosphere, Geophys. Res Lett., 35, L03101, doi:10.1029/2007GL032496, 2008. (published 2 February 2008)

  191. Tsugawa, T., Y. Otsuka, A. J. Coster, and A. Saito, Medium-scale traveling ionospheric disturbances detected with dense and wide TEC maps over North America, Geophys. Res. Lett., 34, L22101, 2007GL031663R, 2007.

  192. Sakaguchi, K., K. Shiokawa, A. Ieda, Y. Miyoshi, Y. Otsuka, T. Ogawa, M. Connors, E. F. Donovan, and F. J. Rich, Simultaneous ground and satellite observations of an isolated proton arc at subauroral latitudes, J. Geophys. Res., 112, A04202, doi:10.1029/2006JA012135, 2007.

  193. Shiokawa, K., S. Suzuki, Y. Otsuka, T. Ogawa, T. Nakamura, and T. Horinouchi, An intense gravity wave near the mesopause region observed by a Fabry-Perot interferometer and an airglow imager, J. Geophys. Res., 112, D07106, doi:10.1029/2006JD007385, 2007.

  194. Kutiev, I., Y. Otsuka, A. Saito, and T. Tsugawa (2007), Low-latitude total electron content enhancement at low geomagnetic activity observed over Japan, J. Geophys. Res., 112, A07306, doi:10.1029/2007JA012385.

  195. Tsugawa, T., S. R- Zhang, A. J. Coster, Y. Otsuka, J. Sato, A. Saito, Y. Zhang, and L. J. Paxton, Summer-winter hemispheric asymmetry of the sudden increase in ionospheric total electron content and of the O/N2 ratio: Solar activity dependence, J. Geophys. Res., 112, A08301, doi:10.1029/2007JA012415, 2007.

  196. Suzuki, S., K. Shiokawa, Y. Otsuka, T. Ogawa, M. Kubota, M. Tsutsumi, T. Nakamura, and D. Fritts (2007), Gravity wave momentum flux in the upper mesosphere derived from OH airglow imaging measurements, Earth Plants Space, 59, 421-428.

  197. Becker-Guedes, F., Y. Sahai, P. R. Fagundes1, E. S. Espinoza, V. G. Pillat, W. L. C. Lima, Su. Basu, Sa. Basu, Y. Otsuka, K. Shiokawa, E. M. MacKenzie, X. Pi, and J. A. Bittencourt, The ionospheric response in the Brazilian sector during the super geomagnetic storm on 20 November 2003, Ann. Geophysicae, 25, 863-873, 2007.

  198. Kotake, N., Y. Otsuka, T. Tsugawa, T. Ogawa, and A. Saito, Statistical study of medium-scale traveling ionospheric disturbances observed with the GPS networks in Southern California, Earth Planets Space, 59, 95-102, 2007.

  199. Shiokawa, K., G. Lu, Y. Otsuka, T. Ogawa, M. Yamamoto, N. Nishitani, and N. Sato, Ground observation and AMIE-TIEGCM modeling of a storm-time traveling ionospheric disturbance, J. Geophys. Res., 112, A05308, doi:10.1029/2006JA011772, 2007.

  200. Suzuki, S., K. Shiokawa, Y. Otsuka, T. Ogawa, K. Nakamura, and T. Nakamura (2007), A concentric gravity wave structure in the mesospheric airglow images, J. Geophys. Res., 112, D02102, doi: 10.1029/2005JD006558.

  201. Kubota, M., S. Kawamura, M. Abo, Y. Koizumi, Y. Murayama, M. Yamamori, K. Shiokawa, Y. Otsuka, M. Uchiumi, K. Igarashi, T. Abe, K.-I. Oyama, and N. Iwagami (2006), A fast-propagating, large-scale atmospheric gravity wave observed in the WAVE2004 campaign, J. Geophys. Res., 111, D21110, doi:10.1029/2005JD006788.

  202. Hosokawa, K, K. Shiokawa Y. Otsuka, A. Nakajima, T. Ogawa, J. D. Kelly, Estimating drift velocity of polar cap patches with all-sky airglow imager at Resolute Bay, Canada, Geophys. Res. Lett., 33, L15111, doi:10.1029/2006GL026916, 2006.

  203. Heki, K., Y. Otsuka, N. Choosakul, N. Hemmakorn, T. Komolmis, and T. Maruyama, Detection of Ruptures of Andaman Fault Segments in the 2004 Great Sumatra Earthquake with Coseismic Ionospheric Disturbances, J. Geophys. Res., 111, B09313, doi:10.1029/2005JB004202, 2006.

  204. Ogawa, T., Y. Otsuka, K. Shiokawa, A. Saito, and M. Nishioka, Ionospheric disturbances over Indonesia and their possible association with atmospheric gravity waves from the troposphere, J. Meteor. Soc. Japan, 84A, 327-342, 2006.

  205. Shiokawa, K., S. Suzuki, Y. Otsuka, T. Ogawa, T. Nakamura, M. G. Mlynczak, and J. M. Russell III, A multi-instrument measurement of a mesospheric front-like structure at the equator, J. Meteor. Soc. Japan, 84A, 305-316, 2006.

  206. Kotake, N., Y. Otsuka, T. Tsugawa, T. Ogawa, and A. Saito, Climatological study of GPS total electron content variations caused by medium-scale traveling ionospheric disturbances, J. Geophys. Res., 111, A04306, doi:10.1029/2005JA011418, 2006.

  207. Tsugawa, T., T. Sadakane, J. Sato, Y. Otsuka, T. Ogawa, K. Shiokawa, and A. Saito, Summer-winter hemispheric asymmetry of sudden increase in ionospheric total electron content induced by solar flares: A role of O/N2 ratio, J. Geophys. Res., 111, A11316, doi:10.1029/2006JA011951, 2006.

  208. Tsugawa, T., K. Shiokawa, Y. Otsuka, T. Ogawa, A. Saito, M. Nishioka, Geomagnetic conjugate observations of large-scale traveling ionospheric disturbances using GPS networks in Japan and Australia, J. Geophys. Res., 111, A02302, 2006.

  209. Shiokawa, K., Y. Otsuka, and T. Ogawa, Quasi-periodic southward-moving waves in 630-nm airglow images in the equatorial thermosphere, J. Geophys. Res., 111, A06301, doi:10.1029/2005JA011406, 2006.

  210. Unnikrishnan, K., A. Saito, Y. Otsuka, M. Yamamoto, and S. Fukao, Transition region of TEC enhancement phenomena during geomagnetically disturbed periods at mid-latitudes, Ann. Geophysicae, 23, 3439-3450, 2005.

  211. Ogawa, T., Y. Otsuka, F. Onoma, K. Shiokawa, and M. Yamamoto, The first coordinated observations of mid-latitude E-region quasi-periodic radar echoes and lower thermospheric 557.7-nm airglow, Ann. Geophysicae, 23, 2391-2399, 2005.

  212. Onoma, F., Y. Otsuka, K. Shiokawa, T. Ogawa, M. Yamamoto, S. Fukao, and S. Saito, Relationship between propagation direction of gravity waves in OH and OI airglow images and VHF radar echo occurrence during the SEEK-2 campaign, Ann. Geophys., 23, 2385-2390, 2005.

  213. Kutiev, I., S. Watanabe, Y. Otsuka, A. Saito, Total electron content behavior over Japan during geomagnetic storms, J. Geophys. Res., 110, A01308, 10.1029/2004JA010586, 2005.

  214. Nakata, H., I. Nagashima, K. Sakata, Y. Otsuka, Y. Akaike, T. Takano, S. Shimakura, K. Shiokawa, T. Ogawa, Observations of equatorial plasma bubbles using broadcast VHF radio waves, Geophys. Res. Lett., Vol. 32, No. 17, L17110, 10.1029/2005GL023243, 2005.

  215. Ogawa, T., E. Sagawa, Y. Otsuka, K. Shiokawa, T. J. Immel, S. B. Mende, and P. Wilkinson, Simultaneous ground- and satellite-based airglow observations of geomagnetic conjugate plasma bubbles in the equatorial anomaly, Earth Planets Space, 57, 385-392, 2005.

  216. Shiokawa, K., Y. Otsuka, T. Tsugawa, T. Ogawa, A. Saito, K. Ohshima, M. Kubota, T. Maruyama, T. Nakamura, M. Yamamoto, and P. Wilkinson, Geomagnetic conjugate observation of nighttime medium- and large-scale traveling ionospheric disturbances: FRONT3 campaign, J. Geophys. Res., 110(A5), A05303, doi:10.1029/2004JA010845, 2005.

  217. Shiokawa, K, Y. Otsuka, T. Ogawa, H. Takahashi, T. Nakamura, and T. Shimomai, Comparison of OH rotational temperatures measured by the spectral airglow temperature imager (SATI) and by a tilting-filter photometer, J. Atmos. Solar-Terr. Phys., 66, 891-897, 2004.

  218. Suzuki, S., K. Shiokawa, Y. Otsuka, T. Ogawa, and P. Wilkinson, Statistical characteristics of gravity waves observed by an all-sky imager at Darwin, Australia, J. Geophys. Res. -Atmospheres, 109, D20S07, doi:10.1029/2003JD004336, 2004.

  219. Shiokawa, K., Y. Otsuka, T. Ogawa, and P. Wilkinson, Time evolution of high-altitude plasma bubbles imaged at geomagnetic conjugate points, Ann. Geophysicae, 22, 3137-3143, 2004.

  220. Nakata, H., Y. Akaike, Y. Otsuka, T. Takano, S. Ujigawa, I. Nagasima, Ray-tracing calculation of VHF radio waves scattered by field-aligned irregularities associated with equatorial plasma bubbles, IEEJ Trans. FM, 124, 1253-1254, 2004.

  221. Tsugawa, T., A. Saito, and Y. Otsuka, A statistical study of large-scale traveling ionospheric disturbances using the GPS network in Japan, J. Geophys. Res., 109, A06302, doi:10.1029/2003JA010302, 2004.

  222. Balan, N., S. Kawamura, T. Nakamura, M. Yamamoto, S. Fukao, K. Igarashi, T. Maruyama, K. Shiokawa, Y. Otsuka, T. Ogawa, H. Alleyne, S. Watanabe, and T. Murayama, Simultaneous mesosphere/lower thermosphere and thermospheric F region observations during geomagnetic storms, J. Geophys. Res., Vol. 109, No. A4, A04308 10.1029/2003JA009982, 2004.

  223. Sahai, Y., P. R. Fagundes, J. R. Abalde, A. A. Pimenta, J. A. Bittencourt, Y. Otsuka, and V. H. Rios, Generation of large-scale equatorial F-region plasma depletions during low spread-F season, Ann. Geophys. 22, 15-23, 2004.

  224. Tsugawa, T., A. Saito, Y. Otsuka, and M. Yamamoto, Damping of large-scale traveling ionospheric disturbances detected with GPS networks during the geomagnetic storm, J. Geophys. Res., 108(A3), 1127, doi:10.1029/2002JA009433, 2003.

  225. Shiokawa, K., Y. Otsuka, T. Ogawa, S. Kawamura, M. Yamamoto, S. Fukao, T. Nakamura, T. Tsuda, N. Balan, K. Igarashi, G. Lu, A. Saito, and K. Yumoto, Thermospheric wind during a storm-time large-scale traveling ionospheric disturbance, J. Geophys. Res., 108(A12), 1423, doi:10.1029/2003JA010001, 2003.

  226. Shiokawa, K., T. Kadota, Y. Otsuka, T. Ogawa, T. Nakamura, T. Tsuda, and S. Fukao, A two-channel Fabry-Perot interferometer with cooled-CCD detectors for neutral wind measurement in the upper atmosphere, Earth Planets Space, 55, 271-275, 2003.

  227. Kawamura, S., N. Balan, Y. Otsuka, and S. Fukao, Annual and semiannual variations of the mid latitude ionosphere under low solar activity, J. Geophys. Res., 107, SIA8-1-10, 0.1029/2001JA000267, 2003.

  228. Ogawa, T., O. Takahashi, Y. Otsuka, K. Nozaki, M. Yamamoto, and K. Kita, Simultaneous middle and upper atmosphere radar and ionospheric sounder obervations of midlatitude E region irregularities and sporadic E layer, J. Geophys. Res., 107, 1275, doi:10.1029/2001JA900176, 2002.

  229. Ping, J., Y. Kono, K. Matsumoto, Y. Otsuka, A. Saito, C. Shum, K. Heki, and N. Kawano, Regional ionosphere map over Japanese Islands, Earth Planets Space, 54, e13-e16, 2002.

  230. Saito, A., M. Nishimura, M. Yamamoto, S. Fukao, T. Tsugawa, Y. Otsuka, S. Miyazaki, and M.C. Kelley, Observations of traveling ionospheric disturbances and 3-m scale irregularities in the nighttime F-region ionosphere with the MU radar and a GPS network, Earth Planets Space, 54, 31-44, 2002.

  231. Ogawa, T., N. Balan, Y. Otsuka, K. Shiokawa, C. Ihara, T. Shimomai, and A. Saito, Observations and modeling of 630 nm airglow and total electron content associated with traveling ionospheric disturbances over Shigaraki, Japan, Earth Planets Space, 54, 45-56, 2002.

  232. Shiokawa, K., Y. Otsuka, M. K. Ejiri, Y. Sahai, T. Kadota, C. Ihara, T. Ogawa, K. Igarashi, S. Miyazaki, and A. Saito, Imaging observations of the equatorward limit of midlatitude traveling ionospheric disturbances, Earth Planets Space, 54, 57-62, 2002.

  233. Balan, N., Y. Otsuka, T. Tsugawa, S. Miyazaki, T. Ogawa, and K. Shiokawa, Plasmaspheric electron content in the GPS ray paths over Japan under magnetically quiet conditions at high solar activity, Earth Planets Space, 54, 71-79, 2002.

  234. Shiokawa, K., Y. Otsuka, C. Ihara, T. Ogawa, and F. J. Rich, Ground and satellite observations of nighttime medium-scale traveling ionospheric disturbance at midlatitude, J. Geophys. Res., 10.1029/2002JA009639, 2003.

  235. Shiokawa, K., C. Ihara, Y. Otsuka, and T. Ogawa, Statistical study of nighttime medium-scale traveling ionospheric disturbances using midlatitude airglow images, J. Geophys. Res., 107, 10.1029/2002JA009491, 2003.

  236. Shiokawa, K., Y. Otsuka, T. Ogawa, N. Balan, K. Igarashi, A. J. Ridley, D. J. Knipp, A. Saito, and K. Yumoto, A large-scale traveling ionospheric disturbance during the magnetic storm of September 15, 1999, J. Geophys. Res., 107(A6), 10.1029/2001JA000245, 2002.

  237. Shiokawa, K., T. Kadota, M. K. Ejiri, Y. Otsuka, Y. Katoh, M. Satoh, and T. Ogawa, Three-channel imaging Fabry-Perot interferometer for midlatitude airglow measurement, Appl. Opt., 40, 4286-4296, 2001.

  238. Saito, A., M. Nishimura, M. Yamamoto, M. Kubota, K. Shiokawa, Y. Otsuka, T. Tsugawa, S. Fukao, T. Ogawa, M. Ishii, T. Sakanoi, and S. Miyazaki, Traveling ionospheric disturbances detected in the FRONT campaign, Geophys. Res. Lett., 28, 689-692, 2001.

  239. Sahai, Y., K. Shiokawa, Y. Otsuka, C. Ihara, T. Ogawa, K. Igarashi, S. Miyazaki, and T. Saito, Imaging observations of mid-latitude ionospheric disturbances during the geomagnetic storm on February 12, 2000, J. Geophys. Res., 106, 24,481-24,492, 2001.

  240. Kawamura, S., Y. Otsuka, S.-R. Zhang, S. Fukao, and W. L. Oliver, A climatology of middle and upper atmosphere radar observations of thermospheric winds, J. Geophys. Res., 105(A6), 12,777-12,788, doi:10.1029/2000JA900013.
  241. Shiokawa, K., Y. Otsuka, T. Ogawa, K. Igarashi, S. Miyazaki, F. J. Rich, A. Saito, K. Yumoto, Comprehensive imaging observations of mid-latitude ionospheric disturbances during storm time substorms, J. Geophys. Res., 105, 27,067-27,080, 2000.

  242. Zhang, S.-R., W. L. Oliver, S. Fukao, and Y. Otsuka, A study of the forenoon ionospheric F/sub 2/ layer behavior over the middle and upper atmospheric radar, J. Geophy. Res., 105, 15,823-15,833, 2000.

  243. Shiokawa, K., M. K. Ejiri, Y. Otsuka, T. Ogawa, M. Kubota, K. Igarashi, A. Saito, and T. Nakamura, Multi-point observations of short-period mesospheric gravity waves over Japan during the FRONT campaign, Geophys. Res. Lett., 24, 4057-4060, 2000.

  244. Kubota, M., K. Shiokawa, M. K. Ejiri, Y. Otsuka, T. Ogawa, T. Sakanoi, H. Fukunishi, M. Yamamoto, S. Fukao, and A. Saito, Traveling ionospheric disturbances observed in the OI 630-nm nightglow images over Japan by using a multi-point imager network during the FRONT campaign, Geophys. Res. Lett., 24, 4037-4040, 2000.

  245. Zhang, S.-R., S. Fukao, W. L. Oliver, and Y. Otsuka, The height of the maximum ionospheric electron density over the MU radar, J. Atmos. Sol.-Terr., 61, 1367-83, 1999.

  246. Kawamura, S., Y. Otsuka, W. L. Oliver, N. Balan, and S. Fukao, MU radar observations of H+ ions in the topside ionosphere, J. Geophy. Res., 103, 20,697-20,704, 1998.

  247. Balan, N., Y. Otsuka, G. J. Bailey, and S. Fukao, Equinoctial asymmetries in the ionosphere and thermosphere observed by the MU radar, J. Geophy. Res., 103, 9481-9495, 1998.

  248. Oliver, W. L., Y. Otsuka, and S. Fukao, MST radar measurement of ionospheric F region winds: The "layer-wind" technique, Radio Sci., 33, 941-948, 1998.

  249. Balan, N., Y. Otsuka, and S. Fukao, New aspects in the annual variation of the ionosphere observed by the MU radar, Geophys. Res. Lett., 24, 2287-2290, 1997.

  250. Oliver, W. L., Y. Otsuka, M. Sato, T. Takami, and S. Fukao, A climatology of F region gravity wave propagation over the middle and upper atmosphere radar J. Geophy. Res., 102, 14,499-14,512, 1997.

  251. Oliver, W. L., S. Fukao, M. Sato, Y. Otsuka, T. Takami, and T. Tsuda, Middle and upper atmosphere radar observations of the dispersion relation for ionospheric gravity waves, J. Geophy. Res., 100, 23,763-23,768, 1995.