Publication List of Refereed Journals


  1. 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)

  2. 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)

  3. 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)

  4. 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)

  5. 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).

  6. 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

  7. 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.)

  8. 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)

  9. 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)

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

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

  18. 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.

  19. 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., 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
  2. 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, Progress in Earth and Planetary Science, PEPS-D-17-000922R, accepted.
  3. 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, accepted.
  4. 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
  5. 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, accepted
  6. Figueiredo, C. A. O. B., C. M. Wrasse, H. Takahashi, Y. Otsuka, K. Shiokawa and D. Barros, Medium scale traveling ionospheric disturbances observed by detrended total electron content maps over Brazil, J. Geophys. Res., accepted, 2018
  7. 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.
  8. 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.
  9. 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.
  10. 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
  11. 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)
  12. 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)
  13. 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)
  14. 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)
  15. 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)
  16. 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)
  17. 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)
  18. 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.
  19. 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.
  20. 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.
  21. 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.
  22. 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.
  23. 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)
  24. 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)
  25. 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)
  26. 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)
  27. 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)
  28. 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)
  29. 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
  30. 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.
  31. 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)
  32. 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
  33. 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)
  34. 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.
  35. 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)
  36. 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)
  37. 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)
  38. 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.
  39. 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.
  40. 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)
  41. 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)
  42. 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)
  43. 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)
  44. 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)
  45. 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)
  46. 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)
  47. 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)
  48. 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)

  49. 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)

  50. 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).

  51. 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)

  52. 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)

  53. 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)

  54. 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)

  55. 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)

  56. 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.)

  57. 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)

  58. 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)

  59. 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.

  60. 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)

  61. 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)

  62. 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).

  63. 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).

  64. 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)

  65. 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).

  66. 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).

  67. 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)

  68. 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)

  69. 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)

  70. 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)

  71. 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)

  72. 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)

  73. 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)

  74. 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)

  75. 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)

  76. 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)

  77. 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)

  78. 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).

  79. 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)

  80. 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)

  81. 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)

  82. 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)

  83. 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)

  84. 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)

  85. 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)

  86. 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.

  87. 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)

  88. 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)

  89. 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)

  90. 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)

  91. 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. (published 14 May 2010)

  92. 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)

  93. 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)

  94. 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)

  95. 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)

  96. 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)

  97. 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)

  98. 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)

  99. 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)

  100. 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)

  101. 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).

  102. 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)

  103. 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)

  104. 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)

  105. 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.)

  106. 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.)

  107. 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)

  108. 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)

  109. 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.)

  110. 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.)

  111. 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)

  112. 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)
  113. 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)

  114. 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)

  115. 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.

  116. 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)

  117. 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)

  118. 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)

  119. 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)

  120. 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)

  121. 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)

  122. 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)

  123. 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.

  124. 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.

  125. 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.

  126. 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.

  127. 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.

  128. 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.

  129. 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.

  130. 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.

  131. 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.

  132. 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.

  133. 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.

  134. 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.

  135. 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.

  136. 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.

  137. 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.

  138. 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.

  139. 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.

  140. 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.

  141. 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.

  142. 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.

  143. 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.

  144. 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.

  145. 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.

  146. 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.

  147. 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.

  148. 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.

  149. 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.

  150. 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.

  151. 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.

  152. 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.

  153. 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.

  154. 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.

  155. 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.

  156. 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.

  157. 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.

  158. 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.

  159. 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.

  160. 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.

  161. 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.

  162. 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.

  163. 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.

  164. 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.

  165. 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.

  166. 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.

  167. 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.

  168. 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.

  169. 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.

  170. 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.

  171. 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.

  172. 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.
  173. 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.

  174. 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.

  175. 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.

  176. 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.

  177. 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.

  178. 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.

  179. 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.

  180. 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.

  181. 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.

  182. 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.

  183. 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.