Editorial Type:
Article
Article Type:
Research Article

Dimension Characteristics and Precipitation Efficiency of Cumulonimbus Clouds in the Region Far South from the Mei-Yu Front over the Eastern Asian Continent

Yukari Shusse Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya, Japan

Search for other papers by Yukari Shusse in
Current site
Google Scholar
PubMed Close
and
Kazuhisa Tsuboki Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya, Japan

Search for other papers by Kazuhisa Tsuboki in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Jul 2006
DOI:
https://doi.org/10.1175/MWR3159.1
Page(s):
1942–1953
Restricted access

Abstract

Dimension characteristics in precipitation properties of cumulonimbus clouds are basic parameters in understanding the vertical transport of water vapor in the atmosphere. In this study, the dimension characteristics and precipitation efficiency of cumulonimbus clouds observed in the Global Energy and Water Cycle Experiment (GEWEX) Asian Monsoon Experiment (GAME) Huaihe River Basin Experiment (HUBEX) are studied using data from X-band Doppler radars and upper-air soundings. The maximum echo area (EAmax) of the cumulonimbus clouds ranged from 0.5 to 470 km2, and the maximum echo top (ETmax) ranged from 2 to 19 km. The total number of cells (TNC) within the cumulonimbus clouds over their lifetime was from 1 to 25.

The ETmax, TNC, area time integral (ATI), and total rainfall amount (Rtot) strongly correlate with the EAmax of the cumulonimbus clouds. The cell-averaged ATI (ATIcell = ATI/TNC), maximum rainfall intensity (RImax), and cell-averaged rainfall amount (Rcell = Rtot/TNC) increase when the EAmax is smaller than 100 km2. On the other hand, they are almost constant when the EAmax is larger than 100 km2. The rain productivity of small clouds (<100 km2 in EAmax) increases not only by the increase of the TNC but also by the intensification of cells, while that of large cumulonimbus clouds (>100 km2 in EAmax) increases by the increase of the TNC rather than by the intensification of cells.

In the present study, precipitation efficiency (εp) is defined as the ratio of the total rainfall amount (Rtot) to the total water vapor amount ingested into the cloud through the cloud base (Vtot). The εp was calculated for six clouds whose vertical velocity data at the cloud-base level were deduced by dual-Doppler analysis throughout their lifetime. The εp ranged from 0.03% to 9.31% and exhibited a strong positive correlation with the EAmax. This indicates that more than 90% of the water vapor that enters the clouds through the cloud base is consumed to moisten the atmosphere and less than 10% is converted to precipitation and returned to the ground. The cumulonimbus clouds in the region far south from the mei-yu front over the eastern Asian continent efficiently transport water vertically and humidify the upper troposphere.

* Current affiliation: Okinawa Subtropical Environment Remote-Sensing Center, National Institute of Information and Communications Technology, Okinawa, Japan

Corresponding author address: Yukari Shusse, Okinawa Subtropical Environment Remote-Sensing Center, National Institute of Information and Communications Technology, 4484 Aza-Onna, Onna, Kunigami, Okinawa 904-0411, Japan. Email: shusse@nict.go.jp

Abstract

Dimension characteristics in precipitation properties of cumulonimbus clouds are basic parameters in understanding the vertical transport of water vapor in the atmosphere. In this study, the dimension characteristics and precipitation efficiency of cumulonimbus clouds observed in the Global Energy and Water Cycle Experiment (GEWEX) Asian Monsoon Experiment (GAME) Huaihe River Basin Experiment (HUBEX) are studied using data from X-band Doppler radars and upper-air soundings. The maximum echo area (EAmax) of the cumulonimbus clouds ranged from 0.5 to 470 km2, and the maximum echo top (ETmax) ranged from 2 to 19 km. The total number of cells (TNC) within the cumulonimbus clouds over their lifetime was from 1 to 25.

The ETmax, TNC, area time integral (ATI), and total rainfall amount (Rtot) strongly correlate with the EAmax of the cumulonimbus clouds. The cell-averaged ATI (ATIcell = ATI/TNC), maximum rainfall intensity (RImax), and cell-averaged rainfall amount (Rcell = Rtot/TNC) increase when the EAmax is smaller than 100 km2. On the other hand, they are almost constant when the EAmax is larger than 100 km2. The rain productivity of small clouds (<100 km2 in EAmax) increases not only by the increase of the TNC but also by the intensification of cells, while that of large cumulonimbus clouds (>100 km2 in EAmax) increases by the increase of the TNC rather than by the intensification of cells.

In the present study, precipitation efficiency (εp) is defined as the ratio of the total rainfall amount (Rtot) to the total water vapor amount ingested into the cloud through the cloud base (Vtot). The εp was calculated for six clouds whose vertical velocity data at the cloud-base level were deduced by dual-Doppler analysis throughout their lifetime. The εp ranged from 0.03% to 9.31% and exhibited a strong positive correlation with the EAmax. This indicates that more than 90% of the water vapor that enters the clouds through the cloud base is consumed to moisten the atmosphere and less than 10% is converted to precipitation and returned to the ground. The cumulonimbus clouds in the region far south from the mei-yu front over the eastern Asian continent efficiently transport water vertically and humidify the upper troposphere.

* Current affiliation: Okinawa Subtropical Environment Remote-Sensing Center, National Institute of Information and Communications Technology, Okinawa, Japan

Corresponding author address: Yukari Shusse, Okinawa Subtropical Environment Remote-Sensing Center, National Institute of Information and Communications Technology, 4484 Aza-Onna, Onna, Kunigami, Okinawa 904-0411, Japan. Email: shusse@nict.go.jp

Save
Cover Monthly Weather Review
Monthly Weather Review

  • Atlas, D., D. Rosenfeld, and D. A. Short, 1990: The estimation of convective rainfall by area integrals. Part I: The theoretical and empirical basis. J. Geophys. Res., 95 , D3. 2153–2160.

    • Search Google Scholar
    • Export Citation

  • Auer, A. H., and J. D. Marwitz, 1968: Estimates of air and moisture flux into hailstorms on the High Plains. J. Appl. Meteor., 7 , 196–198.

    • Search Google Scholar
    • Export Citation

  • Braham Jr., R. R., 1952: The water and energy budgets of the thunderstorm and their relation to thunderstorm development. J. Meteor., 9 , 227–242.

    • Search Google Scholar
    • Export Citation

  • Cressman, G. P., 1959: An operational objective analysis system. Mon. Wea. Rev., 87 , 367–374.

  • Dennis, A. S., A. Koscielaki, D. E. Cain, J. H. Hirsch, and P. L. Smith Jr., 1975: Analysis of radar observations of a randomized cloud seeding experiment. J. Appl. Meteor., 14 , 897–908.

    • Search Google Scholar
    • Export Citation

  • Doneaud, A. A., P. L. Smith, A. S. Dennis, and S. Sengupta, 1981: A simple method for estimating convective rain volume over an area. Water Resour. Res., 17 , 1676–1682.

    • Search Google Scholar
    • Export Citation

  • Doneaud, A. A., S. I. Niscov, D. L. Priegnitz, and P. L. Smith, 1984: The area-time integral as an indicator for convective rain volumes. J. Climate Appl. Meteor., 23 , 555–561.

    • Search Google Scholar
    • Export Citation

  • Doviak, R. J., and D. S. Zrnić, 1984: Doppler Radar and Weather Observations. Academic Press, 458 pp.

  • Fankhauser, J. C., 1971: Thunderstorm–enviroment interactions determined from aircraft and radar observations. Mon. Wea. Rev., 99 , 171–191.

    • Search Google Scholar
    • Export Citation

  • Fankhauser, J. C., 1988: Estimates of thunderstorm precipitation efficiency from field measurements in CCOPE. Mon. Wea. Rev., 116 , 663–684.

    • Search Google Scholar
    • Export Citation

  • Ferrier, B. S., J. Simpson, and W-K. Tao, 1996: Factors responsible for precipitation efficiencies in midlatitude and tropical squall simulations. Mon. Wea. Rev., 124 , 2100–2125.

    • Search Google Scholar
    • Export Citation

  • Foote, G. B., and J. C. Fankhauser, 1973: Airflow and moisture budget beneath a north–east Colorado hailstorm. J. Appl. Meteor., 12 , 1330–1353.

    • Search Google Scholar
    • Export Citation

  • Fujiware, M., 1965: Raindrop-size distribution from individual storms. J. Atmos. Sci., 22 , 585–591.

  • Gagin, A., D. Rosenfeld, and R. E. Lopez, 1985: The relationship between height and precipitation characteristics of summertime convective cells in south Florida. J. Atmos. Sci., 42 , 84–94.

    • Search Google Scholar
    • Export Citation

  • Gal-Chen, T., 1982: Errors in fixed and moving frame of references: Applications for conventional and Doppler radar analysis. J. Atmos. Sci., 39 , 2279–2300.

    • Search Google Scholar
    • Export Citation

  • Imai, I., 1960: Raindrop-size distributions and Z–R relationships. Proc. Eighth Weather Radar Conf., San Francisco, CA, Amer. Meteor. Soc., 211–218.

  • Johnson, L. R., P. L. Smith, T. H. V. Haar, and D. Reinke, 1994: The relationship between area–time integrals determined from satellite infrared data by means of a fixed-threshold approach and convective rainfall volumes. Mon. Wea. Rev., 122 , 440–448.

    • Search Google Scholar
    • Export Citation

  • Jones, D. M. A., 1956: Rainfall drop-size distribution and radar reflectivity. Research Rep. 6, Meteorology Laboratory, Illinois State Water Survey, 20 pp.

  • Kato, K., J. Matsumoto, and H. Iwasaki, 1995: Diurnal variation of Cb-clusters over China and its relation to large-scale conditions in the summer of 1979. J. Meteor. Soc. Japan, 73 , 1219–1234.

    • Search Google Scholar
    • Export Citation

  • Li, L., and S. Senesi, 1997: Properties of the threshold method on a radar rain cluster basis. J. Appl. Meteor., 36 , 1493–1506.

  • Lopez, R. E., 1978: Internal structure and development processes of C-scale aggregates of cumulus clouds. Mon. Wea. Rev., 106 , 1488–1494.

    • Search Google Scholar
    • Export Citation

  • Marshall, J. S., and W. M. Palmer, 1948: The distribution of raindrops with size. J. Meteor., 5 , 165–166.

  • Marwitz, J. D., 1972: Precipitation efficiency of thunderstorms on the high plains. J. Res. Atmos., 6 , 367–370.

  • Nakai, S., and R. Kawamura, 1998: Characteristics of cloud clusters appeared around the Baiu Front: Prevailing scale of organized convection and environmental condition (in Japanese). Tenki, 45 , 895–905.

    • Search Google Scholar
    • Export Citation

  • Rosenfeld, D., and A. Gagin, 1989: Factors governing the total rainfall yield from continental convective clouds. J. Appl. Meteor., 28 , 1015–1030.

    • Search Google Scholar
    • Export Citation

  • Rosenfeld, D., and W. L. Woodley, 2003: Spaceborne inferences of cloud microstructure and precipitation processes: Synthesis, insights, and implications. Cloud Systems, Hurricanes, and the Tropical Rainfall Measuring Mission (TRMM): A Tribute to Dr. Joanne Simpson, Meteor. Monogr., No. 51, Amer. Meteor. Soc., 59–80.

    • Search Google Scholar
    • Export Citation

  • Rosenfeld, D., D. Atlas, and D. A. Short, 1990: The estimation of convective rainfall by area integrals. Part II: The height–area rainfall threshold (HART) method. J. Geophys. Res., 95 , D3. 2161–2176.

    • Search Google Scholar
    • Export Citation

  • Shinoda, T., and H. Uyeda, 2002: Effective factors in the development of deep convective clouds over the wet region of eastern China during the summer monsoon season. J. Meteor. Soc. Japan, 80 , 1395–1414.

    • Search Google Scholar
    • Export Citation

  • Shusse, Y., K. Tsuboki, B. Geng, H. Minda, and T. Takeda, 2005: Structure and evolution of deeply developed convective cells in a long-lived cumulonimbus cloud under a weak vertical wind-shear condition. J. Meteor. Soc. Japan, 83 , 351–371.

    • Search Google Scholar
    • Export Citation

  • Weisman, M. L., and J. B. Klemp, 1982: The dependence of numerically simulated convective storms on vertical wind shear and buoyancy. Mon. Wea. Rev., 110 , 504–520.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 738 293 41
PDF Downloads 402 79 6