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5. Development of a super-pressure balloon for the LODEWAVE (LOng-Duration Experiment of gravity WAVE over Antarctica) (II)

Author

SAITO, Yoshitaka, TOMIKAWA, Yoshihiro, MURATA, Isao, AKITA, Daisuke, NAKASHINO, Kyoichi, MATSUO, Takuma, HASHIMOTO, Hiroyuki, and MATSUSHIMA, Kiyoho

Subjects
LODEWAVE, 大気重力波, Gravity Wave, Scientific Balloon, Super-pressure Balloon, 膜構造物, 科学観測用気球, スーパープレッシャー気球, Membrane Structure
Abstract

南極域での大気重力波観測実験LODEWAVEに向け、スーパープレッシャー気球の開発を進めている。2020年に開発され、耐圧性能、気密性能の要求仕様を満足した体積94m3のNPB01-4気球の体積を倍増させ、要求飛翔高度であった60hPaでの飛翔を可能にした体積182m3のスーパープレッシャー気球NPB02-1気球を開発し、その性能の評価を行った。この気球はポリエチレン皮膜に高張力繊維の網をかぶせることで耐圧性能を向上させ、内部にゴム気球を入れて皮膜を二重にすることで気密性能を強化した気球であり、気球の頭部には、気球内部気圧計測用の気圧計、ガス注入口、排気口が整備され、飛翔試験に利用できる構造を構築したものである。地上試験により、耐圧性能は3,190Pa以上、気密性能は254 時間にわたり正圧を保持する能力が確認された。これは、3kgのペイロードを搭載して、60hPaの気圧高度を254 時間に渡って飛翔可能であることを示しており、LODEWAVEで利用できる性能を有することが確認された。, A prototype super-pressure balloon for the LODEWAVE was developed. Based on the technologies developed for the 94 m3 super-pressure balloon NPB01-4, which was developed in 2020 and satisfied the requirements of the pressure resistance and airtightness except for the flight altitude, a 182 m3 balloon with twice the volume was developed to fly at the pressure altitude of 60 hPa and tested its capabilities. The balloon has the structure covering the polyethylene envelope with a net of high tensile fibers for the high pressure resistance and the double-layer envelope of the polyethylene film balloon and the rubber balloon for the airtightness. In addition, it also equips devices for the flight experiment, including the pressure gauge to measure the gas pressure inside the balloon, the gas input port, and the exhaust port at its top. Through the ground tests, the pressure resistance of more than 3,190 Pa, and the airtightness to hold the positive differential pressure more than 254 hours were confirmed to satisfy the requirements of the LODEWAVE to fly at the pressure altitude of 60 hPa more than 254 hours with 3 kg payload., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA2230025002, レポート番号: JAXA-RR-22-008

Published
2023

6. Local environmental effects on cosmic ray observations at Syowa Station in the Antarctic: PARMA-based snow cover correction for neutrons and machine learning approach for neutrons and muons

Author

Kataoka Ryuho, Sato Tatsuhiko, Kato Chihiro, Kadokura Akira, Kozai Masayoshi, Miyake Shoko, Murase Kiyoka, Yoshida Lihito, Tomikawa Yoshihiro, and Munakata Kazuoki

Subjects
galactic cosmic rays, solar modulation, ground observation, neutron monitor, muon detector, seasonal variation, snow cover, machine learning, echo state network, Meteorology. Climatology, QC851-999
Abstract

Solar modulation of galactic cosmic rays around the solar minimum in 2019–2020 looks different in the secondary neutrons and muons observed at the ground. To compare the solar modulation of primary cosmic rays in detail, we must remove the possible seasonal variations caused by the atmosphere and surrounding environment. As such surrounding environment effects, we evaluate the snow cover effect on neutron count rate and the atmospheric temperature effect on muon count rate, both simultaneously observed at Syowa Station in the Antarctic (69.01° S, 39.59° E). A machine learning technique, Echo State Network (ESN), is applied to estimate both effects hidden in the observed time series of the count rate. We show that the ESN with the input of GDAS data (temperature time series at 925, 850, 700, 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, and 20 hPa) at the local position can be useful for both the temperature correction for muons and snow cover correction for neutrons. The corrected muon count rate starts decreasing in late 2019, preceding the corrected neutron count rate which starts decreasing in early 2020, possibly indicating the rigidity-dependent solar modulation in the heliosphere.

Published
2022
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7. Mesospheric ionization during substorm growth phase

Author

Murase Kiyoka, Kataoka Ryuho, Nishiyama Takanori, Nishimura Koji, Hashimoto Taishi, Tanaka Yoshimasa, Kadokura Akira, Tomikawa Yoshihiro, Tsutsumi Masaki, Ogawa Yasunobu, Uchida Herbert Akihito, Sato Kaoru, Kasahara Satoshi, Mitani Takefumi, Yokota Shoichiro, Hori Tomoaki, Keika Kunihiro, Takashima Takeshi, Kasahara Yoshiya, Matsuda Shoya, Shoji Masafumi, Matsuoka Ayako, Shinohara Iku, Miyoshi Yoshizumi, Sato Tatsuhiko, Ebihara Yusuke, and Tanaka Takashi

Subjects
mesospheric ionization, energetic electron precipitation, substorm, growth phase, Meteorology. Climatology, QC851-999
Abstract

Many studies have been conducted about the impact of energetic charged particles on the atmosphere during geomagnetically active times, while quiet time effects are poorly understood. We identified two energetic electron precipitation (EEP) events during the growth phase of moderate substorms and estimated the mesospheric ionization rate for an EEP event for which the most comprehensive dataset from ground-based and space-born instruments was available. The mesospheric ionization signature reached below 70 km altitude and continued for ~15 min until the substorm onset, as observed by the PANSY radar and imaging riometer at Syowa Station in the Antarctic region. We also used energetic electron flux observed by the Arase and POES 15 satellites as the input for the air-shower simulation code PHITS to quantitatively estimate the mesospheric ionization rate. The calculated ionization level due to the precipitating electrons is consistent with the observed value of cosmic noise absorption. The possible spatial extent of EEP is estimated to be ~8 h MLT in longitude and ~1.5° in latitude from a global magnetohydrodynamic simulation REPPU and the precipitating electron observations by the POES satellite, respectively. Such a significant duration and spatial extent of EEP events suggest a non-negligible contribution of the growth phase EEP to the mesospheric ionization. Combining the cutting-edge observations and simulations, we shed new light on the space weather impact of the EEP events during geomagnetically quiet times, which is important to understand the possible link between the space environment and climate.

Published
2022
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8. Interhemispheric Coupling Study by Observations and Modelling (ICSOM): Concept, Campaigns, and Initial Results

Author

Sato, Kaoru, primary, Tomikawa, Yoshihiro, additional, Kohma, Masashi, additional, Yasui, Ryosuke, additional, Koshin, Dai, additional, Okui, Haruka, additional, Watanabe, Shingo, additional, Miyazaki, Kazuyuki, additional, Tsutsumi, Masaki, additional, Murphy, Damian, additional, Meek, Chris, additional, Tian, Yufang, additional, Ern, Manfred, additional, Baumgarten, Gerd, additional, Chau, Jorge L., additional, Chu, Xinzhao, additional, Collins, Richard, additional, Espy, Patrick J., additional, Hashiguchi, Hiroyuki, additional, Kavanagh, Andrew J., additional, Latteck, Ralph, additional, Lübken, Franz‐Josef, additional, Milla, Marco, additional, Nozawa, Satonori, additional, Ogawa, Yasunobu, additional, Shiokawa, Kazuo, additional, Alexander, M. Joan, additional, Nakamura, Takuji, additional, and Ward, William E., additional

Published
2023
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9. Transient ionization of the mesosphere during auroral breakup: Arase satellite and ground-based conjugate observations at Syowa Station

Author

Kataoka, Ryuho, Nishiyama, Takanori, Tanaka, Yoshimasa, Kadokura, Akira, Uchida, Herbert Akihito, Ebihara, Yusuke, Ejiri, Mitsumu K., Tomikawa, Yoshihiro, Tsutsumi, Masaki, Sato, Kaoru, Miyoshi, Yoshizumi, Shiokawa, Kazuo, Kurita, Satoshi, Kasahara, Yoshiya, Ozaki, Mitsunori, Hosokawa, Keisuke, Matsuda, Shoya, Shinohara, Iku, Takashima, Takeshi, Sato, Tatsuhiko, Mitani, Takefumi, Hori, Tomoaki, and Higashio, Nana

Published
2019
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10. Gravity waves in the mesosphere lower-thermosphere region near Andes observed by airglow imaging at Rio Gallegos (51.6S), Patagonia, Argentina

Author

Nakamura, Takuji, Ejiri, Mitsumu K., Kogure, Masaru, Perwitasari, Septi, Tomikawa, Yoshihiro, Tsutsumi, Masaki, Mizuno, Akira, Tsuno, Katsuhiko, Ogawa, Takayo, Wada, Satoshi, and Salvador, Jacobo

Abstract

Atmospheric gravity waves play important roles in couplings in the terrestrial atmosphere and ionosphere, i.e. in the whole atmosphere, by transporting momentum and energy in vertical and horizontal directions. One of the hotspots, i.e. active source region of such gravity waves, is the area of the Andes and the Antarctic peninsula. In order to study gravity wave activity generated at this hotspot and propagating up to the MLT region,we installed an all-sky airglow camera in November 2017 at Rio Gallegos station (51.6S, 69.3W), Patagonia, Argentina. The imager at Rio Gallegos is equipped with an InGaAs array sensor, sensitive to the near-infrared (900-1700 nm), and can observe OH Meinel band airglow (~87 km altitude), obtaining an OH airglow image every 5 sec with an exposure time of 2 sec. This system has a similar specification with the five imagers of the ANtarctic Gravity Wave Instrument Network (ANGWIN) at Davis, McMurdo, Halley, Syowa and the south pole. In this presentation, we will report the results from Rio Gallegos station, by means of M-transform analysis, which quantitatively derives distributions of short-period gravity wave energy in the horizontal phase velocity domain. Also, comparison with the results from Syowa station in the Antarctic (69.0S, 39.6E) will be presented., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023

12. LODEWAVE (Long-Duration Balloon Experiment of Gravity WAVE over Antarctica)

Author

TOMIKAWA, Yoshihiro, SATO, Kaoru, SAITO, Yoshitaka, MURATA, Isao, HIRASAWA, Naohiko, KOHMA, Masashi, NAKASHINO, Kyoichi, AKITA, Daisuke, MATSUO, Takuma, FUJIWARA, Masatomo, KAHO, Takana, YOSHIDA, Lihito, TOMIKAWA, Yoshihiro, SATO, Kaoru, SAITO, Yoshitaka, MURATA, Isao, HIRASAWA, Naohiko, KOHMA, Masashi, NAKASHINO, Kyoichi, AKITA, Daisuke, MATSUO, Takuma, FUJIWARA, Masatomo, KAHO, Takana, and YOSHIDA, Lihito

Published
2023

13. Interhemispheric Coupling Study by Observations and Modelling (ICSOM): Concept, Campaigns, and Initial Results

Author

Sato, Kaoru, Tomikawa, Yoshihiro, Kohma, Masashi, Yasui, Ryosuke, Koshin, Dai, Okui, Haruka, Watanabe, Shingo, Miyazaki, Kazuyuki, Tsutsumi, Masaki, Murphy, Damian, Meek, Chris, Tian, Yufang, Ern, Manfred, Baumgarten, Gerd, Chau, Jorge L., Chu, Xinzhao, Collins, Richard, Espy, Patrick J., Hashiguchi, Hiroyuki, Kavanagh, Andrew J., Latteck, Ralph, Lübken, Franz‐Josef, Milla, Marco, Nozawa, Satonori, Ogawa, Yasunobu, Shiokawa, Kazuo, Alexander, M. Joan, Nakamura, Takuji, Ward, William E., Sato, Kaoru, Tomikawa, Yoshihiro, Kohma, Masashi, Yasui, Ryosuke, Koshin, Dai, Okui, Haruka, Watanabe, Shingo, Miyazaki, Kazuyuki, Tsutsumi, Masaki, Murphy, Damian, Meek, Chris, Tian, Yufang, Ern, Manfred, Baumgarten, Gerd, Chau, Jorge L., Chu, Xinzhao, Collins, Richard, Espy, Patrick J., Hashiguchi, Hiroyuki, Kavanagh, Andrew J., Latteck, Ralph, Lübken, Franz‐Josef, Milla, Marco, Nozawa, Satonori, Ogawa, Yasunobu, Shiokawa, Kazuo, Alexander, M. Joan, Nakamura, Takuji, and Ward, William E.

Abstract

An international joint research project, entitled Interhemispheric Coupling Study by Observations and Modelling (ICSOM), is ongoing. In the late 2000s, an interesting form of interhemispheric coupling (IHC) was discovered: when warming occurs in the winter polar stratosphere, the upper mesosphere in the summer hemisphere also becomes warmer with a time lag of days. This IHC phenomenon is considered to be a coupling through processes in the middle atmosphere (i.e., stratosphere, mesosphere, and lower thermosphere). Several plausible mechanisms have been proposed so far, but they are still controversial. This is mainly because of the difficulty in observing and simulating gravity waves (GWs) at small scales, despite the important role they are known to play in middle atmosphere dynamics. In this project, by networking sparsely but globally distributed radars, mesospheric GWs have been simultaneously observed in seven boreal winters since 2015/16. We have succeeded in capturing five stratospheric sudden warming events and two polar vortex intensification events. This project also includes the development of a new data assimilation system to generate long-term reanalysis data for the whole middle atmosphere, and simulations by a state-of-the-art GW-permitting general circulation model using the reanalysis data as initial values. By analyzing data from these observations, data assimilation, and model simulation, comprehensive studies to investigate the mechanism of IHC are planned. This paper provides an overview of ICSOM, but even initial results suggest that not only gravity waves but also large-scale waves are important for the mechanism of the IHC.

Published
2023

15. Interhemispheric Coupling Study by Observations and Modelling (ICSOM)

Author

Sato, Kaoru, primary, Tomikawa, Yoshihiro, additional, Kohma, Masashi, additional, Yasui, Ryosuke, additional, Koshin, Dai, additional, Okui, Haruka, additional, Watanabe, Shingo, additional, Miyazaki, Kazuyuki, additional, Tsutsumi, Masaki, additional, Murphy, Damian, additional, Meek, Chris, additional, Tian, Yufang, additional, Ern, Manfred, additional, Baumgarten, Gerd, additional, Chau, Jorge L., additional, Chu, Xinzhao, additional, Collins, Richard L., additional, Espy, Patrick Joseph, additional, Hashiguchi, Hiroyuki, additional, Kavanagh, Andrew John, additional, Latteck, Ralph, additional, Luebken, Franz-Josef, additional, Milla, Marco, additional, Nozawa, Satonori, additional, Ogawa, Yasunobu, additional, Shiokawa, Kazuo, additional, Alexander, M. Joan, additional, Nakamura, Takuji, additional, and Ward, William Edmund, additional

Published
2022
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16. 南極における大気重力波のスーパープレッシャー気球観測計画(LODEWAVE)の第1回キャンペーン観測の結果

Author

TOMIKAWA, Yoshihiro, SATO, Kaoru, SAITO, Yoshitaka, MURATA, Isao, HIRASAWA, Naohiko, KOHMA, Masashi, NAKASHINO, Kyoichi, AKITA, Daisuke, MATSUO, Takuma, FUJIWARA, Masatomo, KAHO, Takana, and YOSHIDA, Lihito

Abstract

大気球シンポジウム 2022年度（2022年11月7-8日. ハイブリッド開催（JAXA相模原キャンパス& オンライン)), Balloon Symposium 2022 (November 7-8, 2022. Hybrid(in-person & online) Conference (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 著者人数: 12名, 資料番号: SA6000177033, レポート番号: isas22-sbs-033

Published
2022

17. 南極における気球とイリジウム衛星間の通信データの分析

Author

KAHO, Takana, SUZUKI, Takato, SAITO, Yoshitaka, and TOMIKAWA, Yoshihiro

Abstract

大気球シンポジウム 2022年度（2022年11月7-8日. ハイブリッド開催（JAXA相模原キャンパス& オンライン)), Balloon Symposium 2022 (November 7-8, 2022. Hybrid(in-person & online) Conference (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000177029, レポート番号: isas22-sbs-029

Published
2022

24. Development of a super-pressure balloon for the LODEWAVE(LOng-Duration Experiment of gravity WAVE over Antarctica)(I)

Author

SAITO, Yoshitaka, IZUMI, Fuyumi, AKITA, Daisuke, NAKASHINO, Kyoichi, MATSUO, Takuma, TOMIKAWA, Yoshihiro, HASHIMOTO, Hiroyuki, and MATSUSHIMA, Kiyoho

Subjects
LODEWAVE, 大気重力波, Gravity Wave, Scientific Balloon, Super-pressure Balloon, 膜構造物, 科学観測用気球, スーパープレッシャー気球, Membrane Structure
Abstract

南極域での大気重力波観測実験LODEWAVEに向け、スーパープレッシャー気球の開発を進めている。体積94立方メートルのスーパープレッシャー気球、NPBO1-4を試作し、その気密性能と耐圧性能を評価した。この気球はポリエチレン皮膜に衛張力繊維の網をかぶせることで耐圧性能を向上させ、内部にゴム気球を入れて皮膜を二重にすることで気密性能を強化した気球である。耐圧性能は3,400Pa、気密性能は289時間にわたり正圧を保持する能力があることがわかった。これは、3kgのペイロードを搭載して、85hPaの気圧高度を289時間に渡って飛翔可能であることを示しており、開発の目処がたった。LODEWAVEで利用できる気球とするには、要求される60hPaの気圧高度を飛翔させるためにもうひとまわりの気球の巨大化、気球の展開の確実性、289時間を越える耐久性、といった改良を加える必要があることも判明した。また、気球圧力の計測方法、気球の放球方法、気球の破壊方法の確立といった飛翔運用時に必要な技術の開発も必要である。今後、これらの開発を実施し、LODEWAVEで利用できる気球の開発を進める。, Development of super-pressure balloons for the LODEWAVE is started. A 94 m3 super-pressure balloon NPB01-4 was developed for the first trial production and tested its capability in the pressure resistance and the gas permeability. This balloon is based on the technologies covering the polyethylene balloon with high-tensile net for the pressure resistance and setting a rubber balloon inside the polyethylene balloon for the gas permeability. For the ground inflation test, the balloon withstood the differential pressure of 3,400 Pa and kept positive differential pressure for 289 hours. These capability shows that the balloon can fly at the atmospheric pressure of 85 hPa for 289 hours with a payload of 3 kg. These results gave us the clear prospect for the development of the super-pressure balloon for the LODEWAVE. Following technical subjects to be solved were also found : 1. Development of slightly larger balloon to fly at the altitude of 60 hPa to meet the requirement from the mission, 2. Stable deployment, 3. Durability beyond 289 hours. In addition, for the flight operation, developments of the technique to measure the inner pressure, the launching procedure, and the termination device are necessary. We are going to solve these problems for the LODEWAVE., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA2030024003, レポート番号: JAXA-RR-20-009

Published
2021

25. LODEWAVE (LOng-Duration balloon Experiment of gravity WAVE over Antarctica)

Author

TOMIKAWA, Yoshihiro, SATO, Kaoru, SAITO, Yoshitaka, MURATA, Isao, HIRASAWA, Naohiko, KOMA, Masashi, NAKASHINO, Kyoichi, AKITA, Daisuke, MATSUO, Takuma, FUJIWARA, Masatomo, and YOSHIDA, Rihito

Subjects
Gravity wave, Antarctic, Super pressure balloon, momentum flux
Abstract

大気重力波は、大気中の運動量輸送を担い、中層大気の子午面循環の駆動を通じて成層圏・中間圏の温度・物質分布の決定に重要な役割を果たす。しかし、重力波の持つ幅広い時空間スケールのすべてを観測で捉える、あるいはモデルで表現することは現在の最新技術をもってしても困難である。特に、重力波に伴う水平運動量の鉛直フラックス（以下、運動量フラックスと略す）は、振幅の小さな鉛直風の情報が必要であり、観測による直接推定は限られる。2011 年に南極昭和基地に設置された大型大気レーダー（PANSY レーダー）は、高精度・高分解能な3 次元風速の観測により、ほぼ全周波数帯の大気重力波の運動量フラックスの鉛直プロファイルを直接推定することができる。また、上空を長期間浮遊するスーパープレッシャー（SP）気球観測では、2 次元風速と気圧の観測により、重力波の運動量輸送を全周波数帯域で定量的に捉えることが可能で、その水平分布もとらえることができる。このSP 気球観測を、大気重力波の観測情報が特に不足している南極域で行い、PANSY レーダー観測および最新の気象再解析データと組み合わせることにより、大気重力波による運動量輸送の3 次元的描像を取得し、将来予測に使用される気候モデルの改良に資することを目的として、南極域における大気重力波のスーパープレッシャー気球観測計画（LODEWAVE）を立案した。本計画では、これまでにSP 気球と搭載機器の開発を進め、2019 年度中にSP 気球の試作と試験、搭載機器の試作を行った。2020 年度中にSP 気球と搭載測器のさらなる開発・試験を行い、2021 年度前半に北海道・大樹航空宇宙実験場での国内気球実験、2021 年度後半に南極昭和基地での試験を兼ねた最大3回のSP 気球観測を計画している。また、本計画で使用するSP 気球と搭載測器は、航空法の制約が緩和される軽量・小型なものとし、将来の南極域での定常的な観測体制構築を目指す。, Atmospheric gravity waves transport momentum in the atmosphere and play an important role in determining temperature and material distribution through driving the meridional circulation in the middle atmosphere. However, they have wide spatial and temporal scales, which make it difficult to capture the whole feature of gravity waves with any of the latest observations and models. The first Mesosphere-Stratosphere-Troposphere (MST)/ Incoherent Scatter (IS) radar in the Antarctic, PANSY, which was installed at Syowa Station in 2011, can directly estimate the momentum flux of gravity waves in all frequency bands by observing 3-dimensional winds with high precision and high resolution. On the other hand, the super pressure (SP) balloon observation can also estimate momentum transport due to gravity waves in all frequency bands, and its horizontal distribution is also clarified. In order to carry out this SP balloon observation in the Antarctic where the observational constraint on the momentum transport due to gravity waves is especially insufficient, we proposed the LOng-Duration balloon Experiment of gravity WAVE over Antarctica (LODEWAVE). By combining it with the PANSY observation and the state-of-the-art meteorological reanalysis data, the 3-dimensional picture of momentum transport due to gravity waves is acquired, which contributes to the improvement of the future prediction by the climate model. We have performed a test production of SP balloon and onboard instruments during FY 2019. The further development and test of the SP balloon and onboard instruments will be carried out in FY 2020. In the first half of FY 2021, a domestic balloon experiment will be carried out at Taiki Aerospace Research Field in Hokkaido. In the latter half of FY 2021, a maximum of 3 SP balloon observations will be carried out at Syowa Station in the Antarctic. By developing the SP balloon and onboard instruments which are light and small enough to ease the restrictions of the Civil Aeronautics Act, we aim to establish a regular observation system in the Antarctic., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA2030024002, レポート番号: JAXA-RR-20-009

Published
2021

26. LODEWAVE実験に向けたスーパープレッシャー気球NPB02-1 の開発

Author

SAITO, Yoshitaka, TOMIKAWA, Yoshihiro, MURATA, Isao, AKITA, Daisuke, NAKASHINO, Kyoichi, MATSUO, Takuma, MATSUSHIMA, Kiyoho, and HASHIMOTO, Hiroyuki

Abstract

第22回宇宙科学シンポジウム (2022年1月6日-7日. オンライン開催), 22nd Space Science Symposium (January 6-7, 2022. Online Meeting), 資料番号: SA6000176164, レポート番号: P-130

Published
2022

28. Propagation Direction Analyses of Medium‐Scale Traveling Ionospheric Disturbances Observed Over North America With GPS‐TEC Perturbation Maps by Three‐Dimensional Spectral Analysis Method

Author

Perwitasari, Septi, primary, Nakamura, Takuji, additional, Tsugawa, Takuya, additional, Nishioka, Michi, additional, Tomikawa, Yoshihiro, additional, Ejiri, Mitsumu K., additional, Kogure, Masaru, additional, Otsuka, Yuichi, additional, Shinbori, Atsuki, additional, Jin, Hidekatsu, additional, and Tao, Chihiro, additional

Published
2022
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29. Mesospheric Short‐Period Gravity Waves in the Antarctic Peninsula Observed in All‐Sky Airglow Images and Their Possible Source Locations

Author

Kam, Hosik, primary, Song, In‐Sun, additional, Kim, Jeong‐Han, additional, Kim, Yong Ha, additional, Song, Byeong‐Gwon, additional, Nakamura, Takuji, additional, Tomikawa, Yoshihiro, additional, Kogure, Masaru, additional, Ejiri, Mitsumu K., additional, Perwitasari, Septi, additional, Tsutsumi, Masaki, additional, and Kwak, Young‐Sil, additional

Published
2021
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30. 南極における大気重力波のスーパープレッシャー気球観測計画(LODEWAVE)の現況２

Author

TOMIKAWA, Yoshihiro, SATO, Kaoru, SAITO, Yoshitaka, MURATA, Isao, HIRAZAWA, Naohiko, KOHRA, Masashi, NAKASHINO, Kyoichi, AKITA, Daisuke, MATSUO, Takuma, FUJIWARA, Masatomo, and YOSHIDA, Lihito

Abstract

大気球シンポジウム 2021年度（2021年11月1-2日. オンライン開催), Balloon Symposium 2021 (November 1-2, 2021. Online Meeting), 著者人数: 11名PDF再処理の為、2023年3月24日に差替, 資料番号: SA6000166033, レポート番号: isas21-sbs-033

Published
2021

34. Role Of the Sun and the Middle atmosphere/thermosphere/ionosphere In Climate (ROSMIC): a retrospective and prospective view

Author

European Commission, Ministerio de Ciencia e Innovación (España), Ward, William, Seppälä, Annika, Yiǧit, Erdal, Nakamura, Takuji, Stolle, Claudia, Laštovička, Jan, Woods, Thomas N., Tomikawa, Yoshihiro, Lübken, Franz-Josef, Solomon, Stanley C., Marsh, Daniel R., Funke, Bernd, Pallamraju, Duggirala, European Commission, Ministerio de Ciencia e Innovación (España), Ward, William, Seppälä, Annika, Yiǧit, Erdal, Nakamura, Takuji, Stolle, Claudia, Laštovička, Jan, Woods, Thomas N., Tomikawa, Yoshihiro, Lübken, Franz-Josef, Solomon, Stanley C., Marsh, Daniel R., Funke, Bernd, and Pallamraju, Duggirala

Abstract

While knowledge of the energy inputs from the Sun (as it is the primary energy source) is important for understanding the solar-terrestrial system, of equal importance is the manner in which the terrestrial part of the system organizes itself in a quasi-equilibrium state to accommodate and re-emit this energy. The ROSMIC project (2014–2018 inclusive) was the component of SCOSTEP’s Variability of the Sun and Its Terrestrial Impact (VarSITI) program which supported research into the terrestrial component of this system. The four themes supported under ROSMIC are solar influence on climate, coupling by dynamics, trends in the mesosphere lower thermosphere, and trends and solar influence in the thermosphere. Over the course of the VarSITI program, scientific advances were made in all four themes. This included improvements in understanding (1) the transport of photochemically produced species from the thermosphere into the lower atmosphere; (2) the manner in which waves produced in the lower atmosphere propagate upward and influence the winds, dynamical variability, and transport of constituents in the mesosphere, ionosphere, and thermosphere; (3) the character of the long-term trends in the mesosphere and lower thermosphere; and (4) the trends and structural changes taking place in the thermosphere. This paper reviews the progress made in these four areas over the past 5 years and summarizes the anticipated research directions in these areas in the future. It also provides a physical context of the elements which maintain the structure of the terrestrial component of this system. The effects that changes to the atmosphere (such as those currently occurring as a result of anthropogenic influences) as well as plausible variations in solar activity may have on the solar terrestrial system need to be understood to support and guide future human activities on Earth. [Figure not available: see fulltext.][Figure not available: see fulltext.][Figure not available: see fulltext

Published
2021

36. Transport and mixing in the extratropical tropopause region in a high-vertical-resolution GCM. Part II: relative importance of large-scale and small-scale dynamics

Author

Miyazaki, Kazuyuki, Sato, Kaoru, Watanabe, Shingo, Tomikawa, Yoshihiro, Kawatani, Yoshio, and Takahashi, Masaaki

Subjects
Meteorological research -- Analysis, Atmospheric circulation -- Models, Earth sciences, Science and technology
Abstract

The relative roles of atmospheric motions on various scales, from mesoscale to planetary scale, in transport and mixing in the extratropical tropopause region are investigated using a high-vertical-resolution general circulation model (GCM). The GCM with a vertical resolution of about 300 m explicitly represents the propagation and breaking of gravity waves and the induced transport and mixing. A downward control calculation shows that the Eliassen--Palm (E-P) flux of the gravity waves diverges and induces a mean equatorward flow in the extratropical tropopause region, which differs from the mean poleward flow induced by the convergence of large-scale E-P fluxes. The diffusion coefficients estimated from the eddy potential vorticity flux in tropopause-based coordinates reveal that isentropic motions diffuse air between 20 K below and 10 K above the tropopause from late autumn to early spring, while vertical mixing is strongly suppressed at around 10-15 K above the tropopause throughout the year. The isentropic mixing is mainly caused by planetary- and synoptic-scale motions, while small-scale motions with a horizontal scale of less than a few thousand kilometers largely affect the three-dimensional mixing just above the tropopause. Analysis of the gravity wave energy and atmospheric instability implies that the small-scale dynamics associated with the dissipation and saturation of gravity waves is a significant cause of the three-dimensional mixing just above the tropopause. A rapid increase in the static stability in the tropopause inversion layer is considered to play an important role in controlling the gravity wave activity around the tropopause. DOI: 10.1175/2009JAS3334.1

Published
2010

37. Transport and mixing in the extratropical tropopause region in a high-vertical-resolution GCM. Part I: potential vorticity and heat budget analysis

Author

Miyazaki, Kazuyuki, Watanabe, Shingo, Kawatani, Yoshio, Tomikawa, Yoshihiro, Takahashi, Masaaki, and Sato, Kaoru

Subjects
Meteorological research -- Analysis, Atmospheric circulation -- Models, Heat budget (Geophysics) -- Research, Vorticity -- Research, Earth sciences, Science and technology
Abstract

A high-vertical-resolution general circulation model (GCM) output has been analyzed to clarify transport and mixing processes in the extratropical tropopause region. The high-resolution GCM, with a vertical resolution of about 300 m above the extratropical upper troposphere, allows simulation of fine atmospheric structures near the tropopause, such as the extratropical tropopause transition layer (ExTL) and the tropopause inversion layer (TIL). The high-resolution GCM realistically simulates fine thermal and dynamic structures in the extratropical tropopause region. The thickness and maximum stability of the simulated TIL are consistent with observations. The high-resolution output was analyzed using a zonal mean potential vorticity (PV) equation to identify dominant transport processes in the extratropical tropopause region. In the Northern Hemisphere extratropics during winter, mean downward advection sharpens the PV gradient between the tropopause and 20 K below it, whereas latitudinal variation in isentropic mixing sharpens the vertical PV gradient between the tropopause and 10 K above it. During summer, vertical mixing substantially sharpens the vertical PV gradient at 10-25 K above the tropopause. These sharpening effects may be strongly related to the formation mechanisms of strong concentration gradients of chemical tracers around the ExTL. Mechanisms of evolution of the TIL are also discussed by analyzing a thermodynamic equation. Downward heat advection and radiation processes primarily determine the seasonality of the TIL. The analysis results suggest that the locations of the TIL and the ExTL can be similar because of common dynamic processes and interactions between constituent distributions and thermal structure. DOI: 10.1175/2009JAS3221.1

Published
2010

39. Development of the super-pressure balloon for LODEWAVE (I)

Author

SAITO, Yoshitaka, IZUMI, Fuyumi, AKITA, Daisuke, NAKASHINO, Kyoichi, MATSUO, Takuma, TOMIKAWA, Yoshihiro, MATSUSHIMA, Kiyoho, and HASHIMOTO, Hiroyuki

Abstract

大気球シンポジウム 2020年度（2020年11月5-6日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)）, 相模原市, 神奈川県, Balloon Symposium 2020 (November 5-6, 2020. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000151025, レポート番号: isas20-sbs-025

Published
2020

40. Chlorine partitioning near the polar vortex edge observed with ground-based FTIR and satellites at Syowa Station, Antarctica, in 2007 and 2011

Author

Nakajima, Hideaki, Murata, Isao, Nagahama, Yoshihiro, Akiyoshi, Hideharu, Saeki, Kosuke, Kinase, Takeshi, Takeda, Masanori, Tomikawa, Yoshihiro, Dupuy, Eric, Jones, Nicholas B, Nakajima, Hideaki, Murata, Isao, Nagahama, Yoshihiro, Akiyoshi, Hideharu, Saeki, Kosuke, Kinase, Takeshi, Takeda, Masanori, Tomikawa, Yoshihiro, Dupuy, Eric, and Jones, Nicholas B

Abstract

2020 Author(s). We retrieved lower stratospheric vertical profiles of O3, HNO3, and HCl from solar spectra taken with a ground-based Fourier transform infrared spectrometer (FTIR) installed at Syowa Station, Antarctica (69.0°S, 39.6°E), from March to December 2007 and September to November 2011. This was the first continuous measurement of chlorine species throughout the ozone hole period from the ground in Antarctica. We analyzed temporal variation of these species combined with ClO, HCl, and HNO3 data taken with the Aura MLS (Microwave Limb Sounder) satellite sensor and ClONO2 data taken with the Envisat MIPAS (the Michelson Interferometer for Passive Atmospheric Sounding) satellite sensor at 18 and 22 km over Syowa Station. An HCl and ClONO2 decrease occurred from the end of May at both 18 and 22 km, and eventually, in early winter, both HCl and ClONO2 were almost depleted. When the sun returned to Antarctica in spring, enhancement of ClO and gradual O3 destruction were observed. During the ClO-enhanced period, a negative correlation between ClO and ClONO2 was observed in the time series of the data at Syowa Station. This negative correlation was associated with the relative distance between Syowa Station and the edge of the polar vortex. We used MIROC3.2 chemistry-climate model (CCM) results to investigate the behavior of whole chlorine and related species inside the polar vortex and the boundary region in more detail. From CCM model results, the rapid conversion of chlorine reservoir species (HCl and ClONO2) into Cl2, gradual conversion of Cl2 into Cl2O2, increase in HOCl in the winter period, increase in ClO when sunlight became available, and conversion of ClO into HCl were successfully reproduced. The HCl decrease in the winter polar vortex core continued to occur due to both transport of ClONO2 from the subpolar region to higher latitudes, providing a flux of ClONO2 from more sunlit latitudes into the polar vortex, and the heterogeneous reaction of HCl with

Published
2020

41. LODEWAVE: LOng-Duration balloon Experiment of gravity WAVE over Antarctica

Author

Tomikawa, Yoshihiro, Kaoru, Sato, Yoshitaka, Saito, Isao, Murata, Naohiko, Hirasawa, Masashi, Kohma, Kyoichi, Nakashino, Daisuke, Akita, Takuma, Matsuo, Masatomo, Fujiwara, and Rihito, Yoshida

Abstract

The Tenth Symposium on Polar Science/Special session: [S] Future plan of Antarctic research: Towards phase X of the Japanese Antarctic Research Project (2022-2028) and beyond, Tue. 3 Dec. / Entrance Hall (1st floor) at National Institute of Polar Research (NIPR)

Published
2019

42. A diagnostic study of waves on the tropopause

Author

Tomikawa, Yoshihiro, Sato, Kaoru, and Shepherd, Theodore G.

Subjects
Cloud physics -- Research, Gravity waves -- Research, Clouds -- Dynamics, Clouds -- Research, Earth sciences, Science and technology
Abstract

The spatial structure and phase velocity of tropopause disturbances localized around the subpolar jet in the Southern Hemisphere are investigated using 6-hourly European Centre for Medium-Range Weather Forecasts reanalysis data covering 15 yr (1979-93). The phase velocity and phase structure of the tropopause disturbances are in good agreement with those of an edge wave vertically trapped at the tropopause. However, the vertical distribution of the ratio of potential to kinetic energy exhibits maxima above and below the tropopause and a minimum around the tropopause, in contradiction to edge wave theory for which the ratio is unity throughout the troposphere and stratosphere. This difference in vertical structure between the observed tropopause disturbances and edge wave theory is attributed to the effects of a finite-depth tropopause together with the next-order corrections in Rossby number to quasigeostrophic dynamics.

Published
2006

44. Wind filtering evidence of mesospheric short-period gravity waves revealed from all-sky images at King Sejong Station (62{degree sign}S, 59{degree sign}W)

Author

Kim, Jeong-Han, primary, Kam, Hosik, additional, Kim, Yong Ha, additional, Song, In-Sun, additional, Song, Byeong-Gwon, additional, Nakamura, Takuji, additional, Tomikawa, Yoshihiro, additional, Kogure, Masaru, additional, Ejiri, Mitsumu K., additional, Perwitasari, Septi, additional, and Tsutsumi, Masaki, additional

Published
2020
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46. Transient ionization of the mesosphere during auroral breakup: Arase satellite and ground-based conjugate observations at Syowa Station

Author

Uchida, Herbert Akihito, Sato, Tatsuhiko, Kataoka, Ryuho, Nishiyama, Takanori, Tanaka, Yoshimasa, Kadokura, Akira, Ebihara, Yusuke, Ejiri, Mitsumu K., Tomikawa, Yoshihiro, Tsutsumi, Masaki, Sato, Kaoru, Miyoshi, Yoshizumi, Shiokawa, Kazuo, Kurita, Satoshi, Kasahara, Yoshiya, Ozaki, Mitsunori, Hosokawa, Keisuke, Matsuda, Shoya, Shinohara, Iku, Takashima, Takeshi, Mitani, Takefumi, Hori, Tomoaki, and Higashio, Nana

Subjects
010504 meteorology & atmospheric sciences, lcsh:Geodesy, Flux, 010502 geochemistry & geophysics, 01 natural sciences, Mesosphere, Ion, Atmosphere, Ionization, X-rays, Absorption (electromagnetic radiation), Cosmic noise, 0105 earth and related environmental sciences, Physics, lcsh:QB275-343, Aurora, lcsh:QE1-996.5, lcsh:Geography. Anthropology. Recreation, Geology, Breakup, Computational physics, lcsh:Geology, lcsh:G, Space and Planetary Science, Energetic electrons
Abstract

著者人数: 23名, Accepted: 2019-01-11, 資料番号: SA1180319000

Published
2019

47. Transient ionization of the mesosphere during auroral breakup: Arase satellite and ground-based conjugate observations at Syowa Station

Author

80342616, 90785495, Kataoka, Ryuho, Nishiyama, Takanori, Tanaka, Yoshimasa, Kadokura, Akira, Uchida, Herbert Akihito, Ebihara, Yusuke, Ejiri, Mitsumu K., Tomikawa, Yoshihiro, Tsutsumi, Masaki, Sato, Kaoru, Miyoshi, Yoshizumi, Shiokawa, Kazuo, Kurita, Satoshi, Kasahara, Yoshiya, Ozaki, Mitsunori, Hosokawa, Keisuke, Matsuda, Shoya, Shinohara, Iku, Takashima, Takeshi, Sato, Tatsuhiko, Mitani, Takefumi, Hori, Tomoaki, Higashio, Nana, 80342616, 90785495, Kataoka, Ryuho, Nishiyama, Takanori, Tanaka, Yoshimasa, Kadokura, Akira, Uchida, Herbert Akihito, Ebihara, Yusuke, Ejiri, Mitsumu K., Tomikawa, Yoshihiro, Tsutsumi, Masaki, Sato, Kaoru, Miyoshi, Yoshizumi, Shiokawa, Kazuo, Kurita, Satoshi, Kasahara, Yoshiya, Ozaki, Mitsunori, Hosokawa, Keisuke, Matsuda, Shoya, Shinohara, Iku, Takashima, Takeshi, Sato, Tatsuhiko, Mitani, Takefumi, Hori, Tomoaki, and Higashio, Nana

Abstract

Transient mesospheric echo in the VHF range was detected at an altitude of 65–70 km during the auroral breakup that occurred from 2220 to 2226 UT on June 30, 2017. During this event, the footprint of the Arase satellite was located within the field of view of the all-sky imagers at Syowa Station in the Antarctic. Auroral observations at Syowa Station revealed the dominant precipitation of relatively soft electrons during the auroral breakup. A corresponding spike in cosmic noise absorption was also observed at Syowa Station, while the Arase satellite observed a flux enhancement of > 100 keV electrons and a broadband noise without detecting chorus waves or electromagnetic ion cyclotron waves. A general-purpose Monte Carlo particle transport simulation code was used to quantitatively evaluate the ionization in the middle atmosphere. Results of this study indicate that the precipitation of energetic electrons of > 100 keV, rather than X-rays from the auroral electrons, played a dominant role in the transient and deep (65–70 km) mesospheric ionization during the observed auroral breakup.

Published
2019

48. 南極における大気重力波のスーパープレッシャー気球観測の現況報告

Author

Tomikawa, Yoshihiro, Sato, Kaoru, Saito, Yoshitaka, Murata, Isao, Hirasawa, Naohiko, and Kohma, Masashi

Abstract

大気球シンポジウム 平成30年度（2018年11月1-2日. 宇宙航空研究開発機構宇宙科学研究所 (JAXA)(ISAS)）, 相模原市, 神奈川県, Balloon Symposium 2018 (November 1-2, 2018. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, 資料番号: SA6000128024, レポート番号: isas18-sbs-024

Published
2018

49. Scientific goals of the whole atmospheric observation by SMILES-2

Author

Baron, Philippe, Liu, Huixin, Saito, Akinori, Shiotani, Masato, Abe, Takumi, Akiyoshi, Hideharu, Fujiwara, Hitoshi, Fujiwara, Masatomo, Imai, Koji, Irimajiri, Yoshihisa, Jin, Hidekatsu, Maezawa, Hiroyuki, Manabe, Takeshi, Manago, Naohiro, Miyoshi, Yasunobu, Mizuno, Akira, Nagahama, Tomoo, Nishibori, Toshiyuki, Ochiai, Satoshi, Otsuka, Yuichi, Oyama, Shinichiro, Sagawa, Hideo, Sakazaki, Takatoshi, Suzuki, Makoto, Tomikawa, Yoshihiro, Uzawa, Yoshinori, and Yamazaki, Atsushi

Abstract

第18回宇宙科学シンポジウム (2018年1月9日-10日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県, 18th Space Science Symposium (January 9-10, 2018. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 著者人数: 27名, 資料番号: SA6000118163, レポート番号: P-130

Published
2018

50. Satellite Observation of the Whole Atmosphere -Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES-2)

Author

SMILES-2ワーキンググループ, Philippe, Baron, Huixin, Liu, SMILES-2, Working Group, Shiotani, Masato, Saito, Akinori, Abe, Takumi, Irimajiri, Yoshihisa, Uzawa, Yoshinori, Otsuka, Yuichi, Oyama, Shinichiro, Ochiai, Satoshi, Sakazaki, Takatoshi, Sagawa, Hideo, Jin, Hidekatsu, Suzuki, Makoto, Tomikawa, Yoshihiro, Nishibori, Toshiyuki, Fujiwara, Hitoshi, Maezawa, Hiroyuki, Miyoshi, Yasunobu, Yamazaki, Atsushi, and Liu, Huixin

Abstract

第18回宇宙科学シンポジウム (2018年1月9日-10日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県, 18th Space Science Symposium (January 9-10, 2018. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS)Sagamihara Campus), Sagamihara, Kanagawa Japan, 著者人数: 20名, 資料番号: SA6000118024, レポート番号: S7-003

Published
2018

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