Seasonal Variations of Volcanic Ash and Aerosol Emissions around Sakurajima Detected by Two Lidars

Two polarization-sensitive lidars were operated continuously to monitor the three-dimensional distribution of small volcanic ash particles around Sakurajima volcano, Kagoshima, Japan. Here, we estimated monthly averaged extinction coefficients of particles between the lidar equipment and the vent and compared our results with monthly records of volcanic activity reported by the Japan Meteorological Agency, namely the numbers of eruptions and explosions, the density of ash fall, and the number of days on which ash fall was observed at the Kagoshima observatory. Elevated extinction coefficients were observed when the surface wind direction was toward the lidar. Peaks in extinction coefficient did not always coincide with peaks in ash fall density, and these differences likely indicate differences in particle size.

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Numerical simulations of the three-dimensional distribution of polar mesospheric clouds and comparisons with Cloud Imaging and Particle Size (CIPS) experiment and the Solar Occultation For Ice Experiment (SOFIE) observations

Journal of Geophysical Research Atmospheres ◽

10.1029/2009jd012451 ◽

2010 ◽

Vol 115 (D10) ◽

Cited By ~ 37

Author(s):

C. G. Bardeen ◽

O. B. Toon ◽

E. J. Jensen ◽

M. E. Hervig ◽

C. E. Randall ◽

...

Keyword(s):

Particle Size ◽

Numerical Simulations ◽

Three Dimensional ◽

Polar Mesospheric Clouds ◽

Solar Occultation ◽

Dimensional Distribution ◽

Mesospheric Clouds

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Assimilation of Himawari-8 imager radiance data with the WRF-3DVAR system for the prediction of Typhoon Soudelor

Natural Hazards and Earth System Science ◽

10.5194/nhess-21-1569-2021 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1569-1582

Author(s):

Feifei Shen ◽

Aiqing Shu ◽

Hong Li ◽

Dongmei Xu ◽

Jinzhong Min

Keyword(s):

Data Assimilation ◽

Inner Core ◽

Surface Wind ◽

Three Dimensional ◽

Background Field ◽

Japan Meteorological Agency ◽

The Pacific ◽

Geostationary Meteorological Satellite ◽

Typhoon Season ◽

Radiance Data

Abstract. Himawari-8 is a next-generation geostationary meteorological satellite launched by the Japan Meteorological Agency. It carries the Advanced Himawari Imager (AHI) on board, which can continuously monitor high-impact weather events with high frequency in space and time. The assimilation of AHI radiance data was implemented with the three-dimensional variational data assimilation system (3DVAR) of the Weather Research and Forecasting Model for the analysis and prediction of Typhoon Soudelor (2015) in the Pacific typhoon season. The effective assimilation of AHI radiance data in improving the forecast of the tropical cyclone during its rapid intensification has been realized. The results show that, after assimilating the AHI radiance data under clear-sky conditions, the typhoon position in the background field of the model was effectively corrected compared with the control experiment without AHI radiance data assimilation. It is found that the assimilation of AHI radiance data is able to improve the analyses of the water vapor and wind in a typhoon's inner-core region. The analyses and forecasts of the minimum sea level pressure, the maximum surface wind, and the track of the typhoon are further improved.

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Assimilation of Himawari-8 Imager Radiance Data with the WRF-3DVAR system for the prediction of Typhoon Soulder

10.5194/nhess-2020-120 ◽

2020 ◽

Author(s):

Dongmei Xu ◽

Aiqing Shu ◽

Zhankui Zhang

Keyword(s):

Inner Core ◽

Surface Wind ◽

Three Dimensional ◽

Surface Wind Speed ◽

Background Field ◽

Japan Meteorological Agency ◽

Near Surface ◽

Frequency Space ◽

Geostationary Meteorological Satellite ◽

Typhoon Season

Abstract. Himawari-8 is a new generation geostationary meteorological satellite launched by Japan Meteorological Agency (JMA). It carries the Advanced Himawari imager (AHI) onboard, which can continuously monitor high-impact weather events with high frequency space and time. The assimilation of AHI was implemented with the framework of the mesoscale numerical model WRF and its three-dimensional variational assimilation system (3DVAR) for the analysis and prediction of typhoon Soudelor in the Pacific Typhoon season in 2015. The effective assimilation of AHI Imager data in tropical cyclone with rapid intensify development has been realized. The results show that after assimilating the AHI imager data under clear sky conditions, the typhoon position in the background field in the model is effectively corrected compared with the control experiment without AHI data. It is found that assimilation of AHI imager data is able to improve the analyses of the water vapor and wind in typhoon inner-core region. The analyses and forecast of the typhoon minimum sea level pressure, the maximum near-surface wind speed, and the typhoon track are further improved．

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Preliminary Results of Weather Radar Observations of Sakurajima Volcanic Smoke

Journal of Disaster Research ◽

10.20965/jdr.2016.p0015 ◽

2016 ◽

Vol 11 (1) ◽

pp. 15-30 ◽

Cited By ~ 15

Author(s):

Masayuki Maki ◽

◽

Masato Iguchi ◽

Takeshi Maesaka ◽

Takahiro Miwa ◽

...

Keyword(s):

Volcanic Ash ◽

Doppler Radar ◽

Three Dimensional ◽

Weather Radar ◽

Fall Velocity ◽

Radar Observations ◽

Preliminary Results ◽

Ash Fall ◽

X Band ◽

Observation Instruments

Preliminary results of quantitative analysis of volcanic ash clouds observed over the Sakurajima volcano in Kagoshima, Japan, were obtained by using weather radar and surface instruments. The Ka-band Doppler radar observations showed the inner structure of a volcanic ash column every two minutes after an eruption. Operational X-band polarimetric radar provides information on three-dimensional ash fall amount distribution. The terminal fall velocity of ash particles was studied by using optical disdrometers, together with the main specifications of observation instruments.

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Improvements of volcanic ash fall forecasts issued by the Japan Meteorological Agency

Journal of Applied Volcanology ◽

10.1186/s13617-014-0018-2 ◽

2015 ◽

Vol 4 (1) ◽

Cited By ~ 8

Author(s):

Yoshihiko Hasegawa ◽

Akira Sugai ◽

Yosuke Hayashi ◽

Yuta Hayashi ◽

Shoji Saito ◽

...

Keyword(s):

Volcanic Ash ◽

Japan Meteorological Agency ◽

Ash Fall

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Three-dimensional distribution of ribulose-1, 5-bisphosphate carboxylase/oxygemase during the early development of proplastids in dark-grown Euglena cells transferred to an inorganic medium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100162090 ◽

1990 ◽

Vol 48 (3) ◽

pp. 906-907

Author(s):

Tomoko Ehara ◽

Shuji Sumida ◽

Tetsuaki Osafune ◽

Eiji Hase

Keyword(s):

Cell Suspension ◽

Euglena Gracilis ◽

Carbon Materials ◽

Three Dimensional ◽

Peripheral Region ◽

Plastid Development ◽

Bisphosphate Carboxylase ◽

Inorganic Medium ◽

Ribulose 1 ◽

Dimensional Distribution

As shown previously, Euglena cells grown in Hutner’s medium in the dark without agitation accumulate wax as well as paramylum, and contain proplastids showing no internal structure except for a single prothylakoid existing close to the envelope. When the cells are transferred to an inorganic medium containing ammonium salt and the cell suspension is aerated in the dark, the wax was oxidatively metabolized, providing carbon materials and energy 23 for some dark processes of plastid development. Under these conditions, pyrenoid-like structures (called “pro-pyrenoids”) are formed at the sites adjacent to the prolamel larbodies (PLB) localized in the peripheral region of the proplastid. The single prothylakoid becomes paired with a newly formed prothylakoid, and a part of the paired prothylakoids is extended, with foldings, in to the “propyrenoid”. In this study, we observed a concentration of RuBisCO in the “propyrenoid” of Euglena gracilis strain Z using immunoelectron microscopy.

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