Vertical cloud structure observed from shipborne radar and lidar: Midlatitude case study during the MR01/K02 cruise of the research vessel Mirai

Hajime Okamoto, Tomoaki Nishizawa, Toshihiko Takemura, Hiroshi Kumagai, Hiroshi Kuroiwa, Nobuo Sugimoto, Ichiro Matsui, Atsushi Shimizu, Seita Emori, Akihide Kamei, Teruyuki Nakajima

    Research output: Contribution to journalArticle

    46 Citations (Scopus)

    Abstract

    We observed the vertical distribution of clouds over the Pacific Ocean near Japan in May 2001 using lidar and a 95-GHz radar on the Research Vessel Mirai. Cloud analyses derived from synergy use of radar and lidar observations showed that there were two local maxima of cirrus cloud frequency of occurrence at 7 and 10.5 km and the drizzle frequency of occurrence was about the half compared with that of clouds below 4 km. The number of layers could be also measured using these schemes. Single, double, triple, and quadruple (or more) cloud layers had a 48, 23, 7, and 2% probability of occurrence, respectively. The average number of cloud layers when clouds existed was 1.54. The vertical structure of clouds observed with the radar/lidar system was compared to clouds in the aerosol transport model SPRINTARS, which is based on the CCSR-NIES Atmospheric General Circulation Model. The cloud fraction, radar reflectivity factor, and lidar backscattering coefficient were simulated by the model and compared to those by the observations using height-time cross-sections where the radar sensitivity was taken into account. The overall pattern of cloud fraction was well reproduced, although the model underestimated (overestimated) mean cloud fraction below 8 km (above 8 km). Cloud microphysics in the model could also be validated through comparison of derived model radar and lidar signals in grid mean with observations. The model overestimated ice particle size above 10 km, and simulated particle sizes in water clouds of 10 μm were larger than observed.

    Original languageEnglish
    Article numberD08216
    JournalJournal of Geophysical Research Atmospheres
    Volume112
    Issue number8
    DOIs
    Publication statusPublished - Apr 27 2007

    Fingerprint

    lidar
    research vessel
    radar
    temperate regions
    Optical radar
    optical radar
    vessels
    Radar
    case studies
    particle size
    Particle size
    General Circulation Models
    aerosols
    occurrences
    Pacific Ocean
    Ice
    Backscattering
    Aerosols
    ice
    Japan

    All Science Journal Classification (ASJC) codes

    • Geophysics
    • Forestry
    • Oceanography
    • Aquatic Science
    • Ecology
    • Water Science and Technology
    • Soil Science
    • Geochemistry and Petrology
    • Earth-Surface Processes
    • Atmospheric Science
    • Earth and Planetary Sciences (miscellaneous)
    • Space and Planetary Science
    • Palaeontology

    Cite this

    Vertical cloud structure observed from shipborne radar and lidar : Midlatitude case study during the MR01/K02 cruise of the research vessel Mirai. / Okamoto, Hajime; Nishizawa, Tomoaki; Takemura, Toshihiko; Kumagai, Hiroshi; Kuroiwa, Hiroshi; Sugimoto, Nobuo; Matsui, Ichiro; Shimizu, Atsushi; Emori, Seita; Kamei, Akihide; Nakajima, Teruyuki.

    In: Journal of Geophysical Research Atmospheres, Vol. 112, No. 8, D08216, 27.04.2007.

    Research output: Contribution to journalArticle

    Okamoto, Hajime ; Nishizawa, Tomoaki ; Takemura, Toshihiko ; Kumagai, Hiroshi ; Kuroiwa, Hiroshi ; Sugimoto, Nobuo ; Matsui, Ichiro ; Shimizu, Atsushi ; Emori, Seita ; Kamei, Akihide ; Nakajima, Teruyuki. / Vertical cloud structure observed from shipborne radar and lidar : Midlatitude case study during the MR01/K02 cruise of the research vessel Mirai. In: Journal of Geophysical Research Atmospheres. 2007 ; Vol. 112, No. 8.
    @article{9fcaadb693874cb392954e150f0aefb2,
    title = "Vertical cloud structure observed from shipborne radar and lidar: Midlatitude case study during the MR01/K02 cruise of the research vessel Mirai",
    abstract = "We observed the vertical distribution of clouds over the Pacific Ocean near Japan in May 2001 using lidar and a 95-GHz radar on the Research Vessel Mirai. Cloud analyses derived from synergy use of radar and lidar observations showed that there were two local maxima of cirrus cloud frequency of occurrence at 7 and 10.5 km and the drizzle frequency of occurrence was about the half compared with that of clouds below 4 km. The number of layers could be also measured using these schemes. Single, double, triple, and quadruple (or more) cloud layers had a 48, 23, 7, and 2{\%} probability of occurrence, respectively. The average number of cloud layers when clouds existed was 1.54. The vertical structure of clouds observed with the radar/lidar system was compared to clouds in the aerosol transport model SPRINTARS, which is based on the CCSR-NIES Atmospheric General Circulation Model. The cloud fraction, radar reflectivity factor, and lidar backscattering coefficient were simulated by the model and compared to those by the observations using height-time cross-sections where the radar sensitivity was taken into account. The overall pattern of cloud fraction was well reproduced, although the model underestimated (overestimated) mean cloud fraction below 8 km (above 8 km). Cloud microphysics in the model could also be validated through comparison of derived model radar and lidar signals in grid mean with observations. The model overestimated ice particle size above 10 km, and simulated particle sizes in water clouds of 10 μm were larger than observed.",
    author = "Hajime Okamoto and Tomoaki Nishizawa and Toshihiko Takemura and Hiroshi Kumagai and Hiroshi Kuroiwa and Nobuo Sugimoto and Ichiro Matsui and Atsushi Shimizu and Seita Emori and Akihide Kamei and Teruyuki Nakajima",
    year = "2007",
    month = "4",
    day = "27",
    doi = "10.1029/2006JD007628",
    language = "English",
    volume = "112",
    journal = "Journal of Geophysical Research",
    issn = "0148-0227",
    number = "8",

    }

    TY - JOUR

    T1 - Vertical cloud structure observed from shipborne radar and lidar

    T2 - Midlatitude case study during the MR01/K02 cruise of the research vessel Mirai

    AU - Okamoto, Hajime

    AU - Nishizawa, Tomoaki

    AU - Takemura, Toshihiko

    AU - Kumagai, Hiroshi

    AU - Kuroiwa, Hiroshi

    AU - Sugimoto, Nobuo

    AU - Matsui, Ichiro

    AU - Shimizu, Atsushi

    AU - Emori, Seita

    AU - Kamei, Akihide

    AU - Nakajima, Teruyuki

    PY - 2007/4/27

    Y1 - 2007/4/27

    N2 - We observed the vertical distribution of clouds over the Pacific Ocean near Japan in May 2001 using lidar and a 95-GHz radar on the Research Vessel Mirai. Cloud analyses derived from synergy use of radar and lidar observations showed that there were two local maxima of cirrus cloud frequency of occurrence at 7 and 10.5 km and the drizzle frequency of occurrence was about the half compared with that of clouds below 4 km. The number of layers could be also measured using these schemes. Single, double, triple, and quadruple (or more) cloud layers had a 48, 23, 7, and 2% probability of occurrence, respectively. The average number of cloud layers when clouds existed was 1.54. The vertical structure of clouds observed with the radar/lidar system was compared to clouds in the aerosol transport model SPRINTARS, which is based on the CCSR-NIES Atmospheric General Circulation Model. The cloud fraction, radar reflectivity factor, and lidar backscattering coefficient were simulated by the model and compared to those by the observations using height-time cross-sections where the radar sensitivity was taken into account. The overall pattern of cloud fraction was well reproduced, although the model underestimated (overestimated) mean cloud fraction below 8 km (above 8 km). Cloud microphysics in the model could also be validated through comparison of derived model radar and lidar signals in grid mean with observations. The model overestimated ice particle size above 10 km, and simulated particle sizes in water clouds of 10 μm were larger than observed.

    AB - We observed the vertical distribution of clouds over the Pacific Ocean near Japan in May 2001 using lidar and a 95-GHz radar on the Research Vessel Mirai. Cloud analyses derived from synergy use of radar and lidar observations showed that there were two local maxima of cirrus cloud frequency of occurrence at 7 and 10.5 km and the drizzle frequency of occurrence was about the half compared with that of clouds below 4 km. The number of layers could be also measured using these schemes. Single, double, triple, and quadruple (or more) cloud layers had a 48, 23, 7, and 2% probability of occurrence, respectively. The average number of cloud layers when clouds existed was 1.54. The vertical structure of clouds observed with the radar/lidar system was compared to clouds in the aerosol transport model SPRINTARS, which is based on the CCSR-NIES Atmospheric General Circulation Model. The cloud fraction, radar reflectivity factor, and lidar backscattering coefficient were simulated by the model and compared to those by the observations using height-time cross-sections where the radar sensitivity was taken into account. The overall pattern of cloud fraction was well reproduced, although the model underestimated (overestimated) mean cloud fraction below 8 km (above 8 km). Cloud microphysics in the model could also be validated through comparison of derived model radar and lidar signals in grid mean with observations. The model overestimated ice particle size above 10 km, and simulated particle sizes in water clouds of 10 μm were larger than observed.

    UR - http://www.scopus.com/inward/record.url?scp=34250646637&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=34250646637&partnerID=8YFLogxK

    U2 - 10.1029/2006JD007628

    DO - 10.1029/2006JD007628

    M3 - Article

    AN - SCOPUS:34250646637

    VL - 112

    JO - Journal of Geophysical Research

    JF - Journal of Geophysical Research

    SN - 0148-0227

    IS - 8

    M1 - D08216

    ER -