Faculty Profiles - SHIOKAWA, Kazuo

Papers - SHIOKAWA, Kazuo

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A concentric gravity wave structure in the mesospheric airglow images Reviewed

Suzuki, S, Shiokawa, K, Otsuka, Y, Ogawa, T, Nakamura, K, Nakamura, T

JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES Vol. 112 ( D2 ) 2007.1

Gravity wave momentum flux in the upper mesosphere derived from OH airglow imaging measurements Reviewed

Suzuki Shin, Shiokawa Kazuo, Otsuka Yuichi, Ogawa Tadahiko, Kubota Minoru, Tsutsumi Masaki, Nakamura Takuji, Fritts David C.

EARTH PLANETS AND SPACE Vol. 59 ( 5 ) page： 421 - 428 2007

Simultaneous DMSP, all-sky camera, and IMAGE FUV observations of the brightening are at a substorm pseudo-breakup Reviewed

Yago K., Shiokawa K., Yumoto K., Baishev D. G., Solovyev S. I., Rich F. J.

EARTH PLANETS AND SPACE Vol. 59 ( 1 ) page： 45 - 49 2007

Development of airglow temperature photometers with cooled-CCD detectors Reviewed

Shiokawa K., Otsuka Y., Suzuki S., Katoh T., Katohl Y., Satoh M., Ogawa T., Takahashi H., Gobbli D., Nakamura T., Williams B. P., She C.-Y., Taguchi M., Shimomai T.

EARTH PLANETS AND SPACE Vol. 59 ( 6 ) page： 585 - 599 2007

The ionospheric response in the Brazilian sector during the super geomagnetic storm on 20 November 2003 Reviewed

Becker-Guedes F., Sahai Y., Fagundes P. R., Espinoza E. S., Pillat V. G., Lima W. L. C., Basu Su., Basu Sa., Otsuka Y., Shiokawa K., MacKenzie E. M., Pi X., Bittencourt J. A.

ANNALES GEOPHYSICAE Vol. 25 ( 4 ) page： 863 - 873 2007

Summer-winter hemispheric asymmetry of sudden increase in ionospheric total electron content induced by solar flares: A role of O/N<sub>2</sub> ratio Reviewed

T. Tsugawa, T. Sadakane, J. Sato, Y. Otsuka, T. Ogawa, K. Shiokawa, A. Saito

Journal of Geophysical Research A: Space Physics Vol. 111 ( A11 ) 2006.11

A fast-propagating, large-scale atmospheric gravity wave observed in the WAVE2004 campaign Reviewed

Minoru Kubota, Seiji Kawamura, Makoto Abo, Yoshiko Koizumi, Yasuhiro Murayama, Miho Yamamori, Kazuo Shiokawa, Yuichi Otsuka, Michihiro Uchiumi, Kiyoshi Igarashi, Takumi Abe, Koh-Ichiro Oyama, Naomoto Iwagami

JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES Vol. 111 ( D21 ) page： D21110 - D21110 2006.11

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER GEOPHYSICAL UNION

The Waves in Airglow Campaign in 2004 (WAVE2004), which aimed to elucidate the formation process of waves in airglow structures from both dynamical and chemical perspectives, was conducted using rocket-borne and ground-based instruments in Japan on 17 January 2004. In this experiment, we observed a large-scale atmospheric gravity wave (AGW), which appeared in both the vertical profiles of sodium density obtained by a Na lidar and the horizontal distributions of airglow emission obtained by an all-sky imager (ASI). Vertical propagation of the AGW accompanied by a shortening of its vertical wavelength was clearly visualized using the Na lidar data. The horizontal wavelength, horizontal phase velocity, period, and propagation direction of the AGW were estimated from the ASI data as 673-774 km, 107-122 m/s, similar to 1.75 hours, and north-northeastward, respectively. Using these parameters and the MF radar wind, vertical wavelengths of the wave were calculated from the dispersion relation of gravity waves. The calculated vertical wavelengths were comparable at altitudes of 85.5 km and 93.25 km to those estimated from the variation of the sodium density. Using a simple ray tracing technique, the AGW was traced back to the southern edge of the distorted jet stream near tropopause. This result strongly suggests that an unstable baroclinic wave associated with ageostrophic motions in the jet stream was the wave source of the large-scale AGW observed in the WAVE2004.

DOI： 10.1029/2005JD006788

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B153 地上からの光学・電波による中間圏重力波の観測(スペシャルセッション「高解像度気候モデルによる中層大気研究の可能性」) Reviewed

中村卓司, 塩川和夫, 堤雅基, 川原琢哉

大会講演予講集 Vol. 90 page： 100 2006.9

Estimating drift velocity of polar cap patches with all-sky airglow imager at Resolute Bay, Canada Reviewed

Hosokawa, K, Shiokawa, K, Otsuka, Y, Nakajima, A, Ogawa, T, Kelly, JD

GEOPHYSICAL RESEARCH LETTERS Vol. 33 ( 15 ) 2006.8

Ionospheric disturbances over Indonesia and their possible association with atmospheric gravity waves from the troposphere Reviewed

Ogawa Tadahiko, Otsuka Yuichi, Shiokawa Kazuo, Saito Akinori, Nishioka Michi

JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN Vol. 84A page： 327 - 342 2006.7

Equatorial ionospheric scintillations and zonal irregularity drifts observed with closely-spaced GPS receivers in Indonesia Reviewed

Otsuka Yuichi, Shiokawa Kazuo, Ogawa Tadahiko

JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN Vol. 84A page： 343 - 351 2006.7

A multi-instrument measurement of a mesospheric front-like structure at the equator Reviewed

Shiokawa Kazuo, Suzuki Shin, Otsuka Yuichi, Ogawa Tadahiko, Nakamura Takuji, Mlynczak Martin G., Russell James M. III

JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN Vol. 84A page： 305 - 316 2006.7

Quasiperiodic southward moving waves in 630-nm airglow images in the equatorial thermosphere Reviewed Open Access

Shiokawa, K, Otsuka, Y, Ogawa, T

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 111 ( A6 ) 2006.6

Language：English Publishing type：Research paper (scientific journal) Publisher：Blackwell Publishing Ltd

We report quasiperiodic southward moving waves, which are commonly observed in the 01 630-nm airglow images (emission altitudes of 200-300 km) near the equator, in 2-year airglow observations at Kototabang, Indonesia (0.2°S, 100.3°E, geomagnetic latitude of -10.4°). The waves have predominantly east-west phase fronts and repeatedly propagate southward with a velocity of 310 ± 110 m/s and a period of 40 ± 15 min. They are frequently observed in May-July with an occurrence rate of 53% and are also observed in other seasons with occurrences of ∼20%. The waves are observed in and to the south (geomagnetically poleward) of the equatorial ionospheric anomaly, which is identified as an airglow enhancement region moving gradually to lower geomagnetic latitudes at the premidnight local times. We suggest that gravity waves in the lower thermosphere below ∼300 km are a plausible cause of the observed quasiperiodic waves in the airglow images. Copyright 2006 by the American Geophysical Union.

DOI： 10.1029/2005JA011406

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Scopus

Geomagnetic conjugate observations of large-scale traveling ionospheric disturbances using GPS networks in Japan and Australia Reviewed

Takuya Tsugawa, Kazuo Shiokawa, Yuichi Otsuka, Tadahiko Ogawa, Akinori Saito, Michi Nishioka

Journal of Geophysical Research: Space Physics Vol. 111 ( A2 ) 2006.2

Language：English Publishing type：Research paper (scientific journal) Publisher：Blackwell Publishing Ltd

The geomagnetic conjugacy of large-scale traveling ionospheric disturbances (LSTIDs) was studied using total electron content (TEC) data derived from GPS networks in Japan and Australia. The number of simultaneous occurrences of LSTIDs within ±1 hour in both hemispheres was 5 out of 20 (21) events in Japan (Australia) when Kp ≥ 5- and 0 out of 15 (10) when Kp ≤ 4+. As for the LSTIDs observed simultaneously in both hemispheres, the propagation velocities of equatorward LSTID were comparable between the two hemispheres, with differences of 10-40%. The crossing times at 30° geomagnetic latitude of the simultaneous LSTIDs over Japan and Australia were also different by several tens of minutes for all five events. These observational results indicate that the LSTIDs observed almost simultaneously in both hemispheres are not connected electromagnetically through the geomagnetic field but are generated by atmospheric gravity waves propagating to the equator independently in the two hemispheres. Copyright 2006 by the American Geophysical Union.

DOI： 10.1029/2005JA011300

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Scopus

ERG - A small-satellite mission to investigate the dynamics of the inner magnetosphere Reviewed

Shiokawa K., Seki K., Miyoshi Y., Ieda A., Ono T., Iizima M., Nagatsuma T., Obara T., Takashima T., Asamura K., Kasaba Y., Matsuoka A., Saito Y., Saito H., Hirahara M., Tonegawa Y., Toyama F., Tanaka M., Nose M., Kasahara Y., Yumoto K., Kawano H., Yoshikawa A., Ebihara Y., Yukimatsu A., Sato N., Watanabe S.

MAGNETOSPHERIC DYNAMICS AND THE INTERNATIONAL LIVING WITH A STAR PROGRAM Vol. 38 ( 8 ) page： 1861-1869 2006

Signatures of 3-6 day planetary waves in the equatorial mesosphere and ionosphere Reviewed

Takahashi H., Wrasse C. M., Pancheva D., Abdu M. A., Batista I. S., Lima L. M., Batista P. P., Clemesha B. R., Shiokawa K.

ANNALES GEOPHYSICAE Vol. 24 ( 12 ) page： 3343 - 3350 2006

GPS detection of total electron content variations over Indonesia and Thailand following the 26 December 2004 earthquake Reviewed

Otsuka Y, Kotake N, Tsugawa T, Shiokawa K, Ogawa T, Effendy, Saito S, Kawamura M, Maruyama T, Hemmakorn N, Komolmis T

EARTH PLANETS AND SPACE Vol. 58 ( 2 ) page： 159 - 165 2006

the Inner Magnetosphere Subgroup in the Society of Geomagnetism and Earth, Planetary and Space Sciences ERG -A small-satellite mission to investigate the dynamics of the inner magnetosphere Reviewed

塩川和夫

Adv. Space Res 38(8) page： 1861 - 1869 2006

Effects of the major geomagnetic storms of October 2003 on the equatorial and low-latitude F region in two longitudinal sectors Reviewed

Y Sahai, PR Fagundes, F Becker-Guedes, MJA Bolzan, Abalde, JR, VG Pillat, R de Jesus, WLC Lima, G Crowley, K Shiokawa, JW MacDougall, HT Lan, K Igarashi, JA Bittencourt

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 110 ( A12 ) 2005.12

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER GEOPHYSICAL UNION

The intense modifications in the ionosphere-thermosphere system in the equatorial and low-latitude regions associated with the dynamic and electrodynamic coupling from high to low latitudes and chemical changes during geomagnetic storms are important space weather issues. In the second half of October 2003, the intense solar activity resulted in one intense and two major geomagnetic storms on 29 and 30 October. In this paper we present and discuss the ionospheric sounding observations carried out from Palmas and Sao Jose dos Campos, Brazil (the Brazilian sector), and Ho Chi Minh City, Vietnam, and Okinawa, Japan (the East Asian sector), during these storms. The two sectors are separated by about 12 hours in local time (so while one sector is in daytime, the other one is in nighttime) and provide valuable information related to the storm-time longitudinal differences. Copious storm-time changes were observed in both sectors. It should be pointed out that the two longitudinal sectors investigated in the present study clearly show the global nature of the storm-time effects. However, the responses to the storm-time effects are also associated with the local time in the two sectors. The present investigations show that there are both similarities and differences in the storm-time response in the two sectors. During the storm main phases, with sharp decreases of the Dst index, both sectors showed (dusk or dawn periods) fast uplifting of the F layer associated with magnetospheric electric field penetration. Although in the East Asian sector, Ho Chi Minh City and Okinawa are located fairly close in longitude, with only 2 hour difference in local lime, on occasions the storm-time responses have been very different. Some differences in the latitudinal response of the F region were also observed in the two sectors. Both positive and negative storm phases have been observed at all the four stations. A comparison of the ionospheric parameters obtained from the TIMEGCM model runs and the observed ionospheric parameters at the four stations shows a reasonable agreement during the quiet periods. During the geomagnetic disturbance period, when there were sharp decreases in Dst, some of the observed rapid uplifts of the F region peak heights are not reproduced by the model results. Also, sometimes the model foF2 results differ considerably from the observed foF2 variations. The period investigated represents an extreme storm situation for validation of the model and points to ways in which the model might be improved in the future.

DOI： 10.1029/2004JA010999

Web of Science

Scopus

Ground and satellite observations of substorm onset arcs Reviewed Open Access

K Shiokawa, K Yago, K Yumoto, DG Baishev, SI Solovyev, FJ Rich, SB Mende

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS Vol. 110 ( A12 ) 2005.12

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER GEOPHYSICAL UNION

[1] Auroral features and associated particles and fields are investigated for a sequence of substorm onsets observed at similar to 1900 MLT on 24 October 2000. During a 30-min interval at 1020 - 1050 UT, we identified three Pi 2 wave packets with positive H enhancements at midlatitudes and associated auroral brightenings in auroral images obtained by a ground all-sky camera and the IMAGE FUV imager. The DMSP F15 satellite crossed brightening arcs during the third Pi 2 pulsation in the field-of-view of the ground camera at Tixie (66.0 degrees MLAT), Russia. The crossing was 1 - 2 hours duskside of the main onset local time. The brightening arcs were located in the region 1 upward field-aligned current system. The most equatorward arc, which brightened just after the second Pi 2 pulsation, was at the equatorward boundary of the region 1 current and in the sunward convection region. The arcs corresponded to inverted-V accelerated electrons with energies of similar to 10 keV. On the basis of these simultaneous ground-satellite measurements, we discuss substorm onset models of reconnection/ flow braking and near-Earth plasma sheet instabilities.

DOI： 10.1029/2005JA011281

Web of Science

Scopus

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Papers - SHIOKAWA, Kazuo