• Anderson, S. P., , R. A. Weller, , and R. Lukas, 1996: Surface buoyancy forcing and the mixed layer of the western Pacific warm pool: Observations and 1D model results. J. Climate, 9 , 30563085.

    • Search Google Scholar
    • Export Citation
  • Browning, K. A., 1994: Survey of perceived priority issues in the parameterizations of cloud-related processes in GCMs. Quart. J. Roy. Meteor. Soc., 120 , 483487.

    • Search Google Scholar
    • Export Citation
  • Cess, R. D., and Coauthors. 1989: Interpretation of cloud-climate feedback as produced by 14 atmospheric general circulation models. Science, 245 , 513516.

    • Search Google Scholar
    • Export Citation
  • Chahine, M. T., 1992: The hydrological cycle and its influence on climate. Nature, 359 , 373380.

  • Clark, T. L., , W. D. Hall, , and J. L. Coen, 1996: Source code documentation for the Clark–Hall cloud-scale model: Code version G3CH01. NCAR Tech. Note NCAR/TN-426+STR, 137 pp. [Available from NCAR Information Service, P.O. Box 3000, Boulder, CO 80307.].

    • Search Google Scholar
    • Export Citation
  • Del Genio, A. D., , M-S. Yao, , W. Kovari, , and L. W. Lo, 1996: A prognostic cloud water parameterization for global climate models. J. Climate, 9 , 270304.

    • Search Google Scholar
    • Export Citation
  • Emanuel, K. A., 1991: A scheme for representing cumulus convection in large-scale models. J. Atmos. Sci., 48 , 23132335.

  • Emanuel, K. A., , and R. T. Pierrehumbert, 1996: Microphysical and dynamical control of tropospheric water vapor. Clouds, Chemistry and Climate, P. J. Crutzen and V. Ramanathan, Eds., NATO ASI Series, Vol. 135, Springer-Verlag, 17–28.

    • Search Google Scholar
    • Export Citation
  • Fairall, C. W., , E. F. Bradley, , D. P. Rogers, , J. B. Edson, , and G. S. Young, 1996: Bulk parameterization of air–sea fluxes for Tropical Ocean-Global Atmosphere Coupled-Ocean Atmosphere Response Experiment. J. Geophys. Res., 101 , 37473764.

    • Search Google Scholar
    • Export Citation
  • Fowler, L., , D. A. Randall, , and S. A. Rutledge, 1996: Liquid and ice cloud microphysics in the CSU general circulation model. Part I: Model description and simulated microphysical processes. J. Climate, 9 , 489529.

    • Search Google Scholar
    • Export Citation
  • Fu, Q., , S. K. Frueger, , and K. N. Liou, 1995: Interactions of radiation and convection in simulated tropical cloud clusters. J. Atmos. Sci., 52 , 13101328.

    • Search Google Scholar
    • Export Citation
  • Fu, R., , A. D. Del Genio, , W. B. Rossow, , and W. T. Liu, 1992: Cirrus-cloud thermostat for tropical sea surface temperatures tested using satellite data. Nature, 358 , 394397.

    • Search Google Scholar
    • Export Citation
  • Gent, P. R., 1991: The heat budget of the TOGA-COARE domain in an ocean model. J. Geophys. Res., 96 , 33233330.

  • Gill, A. E., , and E. M. Rasmusson, 1983: The 1982–83 climate anomaly in the equatorial Pacific. Nature, 306 , 229234.

  • Grabowski, W. W., 2000: Cloud microphysics and the tropical climate: Cloud-resolving model perspective. J. Climate, 13 , 23062322.

  • Grabowski, W. W., , M. W. Moncrieff, , and J. T. Kiehl, 1996a: Long-term behavior of precipitating tropical cloud systems: A numerical study. Quart. J. Roy. Meteor. Soc., 122 , 10191042.

    • Search Google Scholar
    • Export Citation
  • Grabowski, W. W., , X. Wu, , and M. W. Moncrieff, 1996b: Cloud resolving modeling of tropical cloud systems during Phase III of GATE. Part I: Two-dimensional experiments. J. Atmos. Sci., 53 , 36843709.

    • Search Google Scholar
    • Export Citation
  • Grabowski, W. W., , X. Wu, , and M. W. Moncrieff, . 1999: Cloud resolving modeling of tropical cloud systems during Phase III of GATE. Part III: Effects of cloud microphysics. J. Atmos. Sci., 56 , 23842402.

    • Search Google Scholar
    • Export Citation
  • Held, I. M., , R. S. Hemler, , and V. Ramaswamy, 1993: Radiative–convective equilibrium with explicit two-dimensional moist convection. J. Atmos. Sci., 50 , 39093927.

    • Search Google Scholar
    • Export Citation
  • Heymsfield, A. J., , and J. Iaquinta, 2000: Cirrus crystal terminal velocities. J. Atmos. Sci., 57 , 916938.

  • Kessler, E., 1969: On the Distribution and Continuity of Water Substance in Atmospheric Circulations, Meteor. Monogr.,. No. 32, Amer. Meteor. Soc., 84 pp.

    • Search Google Scholar
    • Export Citation
  • Kiehl, J. T., , J. J. Hack, , and B. P. Briegleb, 1994: The simulated Earth radiation budget of the National Center for Atmospheric Research community climate model CCM2 and comparisons with the Earth Radiation Budget Experiment (ERBE). J. Geophys. Res., 99 , 2081520827.

    • Search Google Scholar
    • Export Citation
  • Koenig, L. R., , and F. W. Murray, 1976: Ice-bearing cumulus clouds evolution: Numerical simulation and general comparison against observations. J. Appl. Meteor., 15 , 747762.

    • Search Google Scholar
    • Export Citation
  • Krueger, S. K., , Q. Fu, , K. N. Liou, , and H-N. Chin, 1995: Improvements of an ice-phase microphysics parameterization for use in numerical simulation of tropical convection. J. Appl. Meteor., 34 , 281287.

    • Search Google Scholar
    • Export Citation
  • Large, W. G., , and P. R. Gent, 1999: Validation of vertical mixing in an equatorial ocean model using large eddy simulations and observations. J. Phys. Oceanogr., 29 , 449464.

    • Search Google Scholar
    • Export Citation
  • Large, W. G., , J. C. McWilliams, , and S. C. Doney, 1994: Oceanic vertical mixing: A review and a model with a nonlocal boundary layer parameterization. Rev. Geophys., 32 , 363403.

    • Search Google Scholar
    • Export Citation
  • Lau, K-M., , C-H. Sui, , and W-K. Tao, 1993: A preliminary study of the tropical water cycle and its sensitivity to surface warming. Bull. Amer. Meteor. Soc., 74 , 13131321.

    • Search Google Scholar
    • Export Citation
  • Li, X., , C-H. Sui, , D. Adamec, , and K-M. Lau, 1998: Impacts of precipitation in the upper ocean in the western Pacific warm pool during TOGA-COARE. J. Geophys. Res., 103 , 53475359.

    • Search Google Scholar
    • Export Citation
  • Li, X., , C-H. Sui, , K-M. Lau, , and M-D. Chou, 1999: Large-scale forcing and cloud-radiation interaction in the tropical deep convective regime. J. Atmos. Sci., 56 , 30283042.

    • Search Google Scholar
    • Export Citation
  • Li, X., , C-H. Sui, , K-M. Lau, , and D. Adamec, 2000: Effects of precipitation on ocean mixed-layer temperature and salinity as simulated in a 2-D coupled ocean–cloud resolving atmosphere model. J. Meteor. Soc. Japan, 78 , 647659.

    • Search Google Scholar
    • Export Citation
  • Lin, X., , and R. H. Johnson, 1996: Kinematic and thermodynamic characteristics of the flow over the western pacific warm pool during TOGA COARE. J. Atmos. Sci., 53 , 695715.

    • Search Google Scholar
    • Export Citation
  • McFarquhar, G. M., , and A. J. Heymsfield, 1996: Microphysical characteristics of three cirrus anvils sampled during the Central Equatorial Pacific Experiment. J. Atmos. Sci., 53 , 24012423.

    • Search Google Scholar
    • Export Citation
  • Mitchell, J. F. B., , C. A. Senior, , and W. J. Ingram, 1989: CO2 and climate: A missing feedback? Nature, 341 , 132134.

  • Ramanathan, V., , and W. Collins, 1991: Thermodynamic regulation of ocean warming by cirrus clouds deduced from observations of the 1987 El Niño. Nature, 351 , 2732.

    • Search Google Scholar
    • Export Citation
  • Randall, D. A., , Harshvardhan, , D. A. Dazlich, , and T. G. Corsetti, 1989: Interactions among radiation, convection, and large-scale dynamics in a general circulation model. J. Atmos. Sci., 46 , 19431970.

    • Search Google Scholar
    • Export Citation
  • Rasch, P. J., , and J. E. Kristjánsson, 1998: A comparison of the CCM3 model climate using diagnosed and predicted condensate parameterizations. J. Climate, 11 , 15871614.

    • Search Google Scholar
    • Export Citation
  • Senior, C. A., , and J. F. B. Mitchell, 1993: Carbon dioxide and climate: The impact of cloud parameterization. J. Climate, 6 , 393418.

  • Smagorinsky, J., 1963: General circulation experiments with the primitive equations. I. The basic experiment. Mon. Wea. Rev., 91 , 99164.

    • Search Google Scholar
    • Export Citation
  • Sui, C-H., , K. M. Lau, , W-K. Tao, , and J. Simpson, 1994: The tropical water and energy cycles in a cumulus ensemble model. Part I: Equilibrium climate. J. Atmos. Sci., 51 , 711728.

    • Search Google Scholar
    • Export Citation
  • Sui, C-H., , X. Li, , K. M. Lau, , and D. Adamec, 1997: Multiscale air–sea interactions during TOGA COARE. Mon. Wea. Rev., 125 , 448462.

  • Sui, C-H., , X. Li, , and K. M. Lau, . 1998: Selective absorption of solar radiation and upper ocean temperature in the equatorial western Pacific. J. Geophys. Res., 103 , 1031310321.

    • Search Google Scholar
    • Export Citation
  • Sun, D-Z., , and R. S. Lindzen, 1993: Distribution of tropical tropospheric water vapor. J. Atmos. Sci., 50 , 16431660.

  • Sundqvist, H., 1993: Parameterization of clouds in large-scale numerical models. Aerosol–Cloud–Climate Interactions, P. V. Hobbs, Ed., Vol. 1, Academic Press, 175–203.

    • Search Google Scholar
    • Export Citation
  • Tao, W-K., , J. Simpson, , C-H. Sui, , C-L. Shie, , B. Zhou, , K-M. Lau, , and M. W. Moncrieff, 1999: Equilibrium states simulated by cloud-resolving models. J. Atmos. Sci., 56 , 31283139.

    • Search Google Scholar
    • Export Citation
  • Tompkins, A. M., , and G. C. Craig, 1999: Sensitivity of tropical convection to sea surface temperature in the absence of large-scale flow. J. Climate, 12 , 462476.

    • Search Google Scholar
    • Export Citation
  • Twomey, S. A., , M. Piepgrass, , and T. L. Wolfe, 1984: An assessment of the impact of pollution on global cloud albedo. Tellus, 36B , 356366.

    • Search Google Scholar
    • Export Citation
  • Wetherald, R. T., , and S. Manabe, 1988: Cloud feedback processes in a general circulation model. J. Atmos. Sci., 45 , 13971415.

  • Wu, X., , and M. W. Moncrieff, 1999: Effects of sea surface temperature and large-scale dynamics on the thermodynamic equilibrium state and convection over the tropical western Pacific. J. Geophys. Res., 104 , 60936100.

    • Search Google Scholar
    • Export Citation
  • Wu, X., , and M. W. Moncrieff, . 2001: Long-term behavior of cloud systems in TOGA COARE and their interactions with radiative and surface processes. Part III: Effects on the energy budget and SST. J. Atmos. Sci., 58 , 11551168.

    • Search Google Scholar
    • Export Citation
  • Wu, X., , W. W. Grabowski, , and M. W. Moncrieff, 1998: Long-term behavior of cloud systems in TOGA COARE and their interactions with radiative and surface processes. Part I: Two-dimensional modeling study. J. Atmos. Sci., 55 , 26932714.

    • Search Google Scholar
    • Export Citation
  • Wu, X., , W. D. Hall, , W. W. Grabowski, , M. W. Moncrieff, , W. D. Collins, , and J. T. Kiehl, 1999: Long-term behavior of cloud systems in TOGA COARE and their interactions with radiative and surface processes. Part II: Effects of ice microphysics on cloud–radiation interaction. J. Atmos. Sci., 56 , 31773195.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 152 152 84
PDF Downloads 106 106 0

Effects of Ice Microphysics on Tropical Radiative–Convective–Oceanic Quasi-Equilibrium States

View More View Less
  • 1 National Center for Atmospheric Research,* Boulder, Colorado
© Get Permissions Rent on DeepDyve
Restricted access

Abstract

The effects of ice microphysics on the mean state of tropical atmosphere and ocean are quantified using a coupled cloud–ocean model. The cloud-resolving model (CRM) treats explicitly the cloud-scale dynamics instead of using parameterization as is necessary in a general circulation model (GCM). The ocean model is a one-dimensional (1D) mixed layer model with a nonlocal K-profile parameterization to represent the vertical mixing in the oceanic surface boundary layer. Two sets of 40-day simulations attain radiative–convective–oceanic quasi-equilibrium states, one is a coupled simulation, the other has a fixed sea surface temperature (SST). Each set consists of two simulations, with a larger and smaller ice fall speed, respectively.

The two coupled simulations (T0C and M2C) yield dramatically different radiative–convective–oceanic quasi-equilibrium states demonstrating the profound impact of ice microphysics on the water vapor, cloud, and radiation fields. The mean SST and mixed layer depth in M2C is 0.67 K colder and 33 m deeper than those in T0C, and the net surface solar radiation in M2C is 88 W m−2 smaller than that in T0C. The simulation associated with the larger ice fall speed achieves a quasi-equilibrium state characterized by a colder and drier atmosphere, less cloudiness, stronger convection and precipitation, and warmer SST. On the other hand, a quasi-equilibrium state associated with the smaller ice fall speed has a warmer and moister atmosphere, more cloudiness, weaker convection and precipitation, and colder SST. The key mechanism is cloud–radiation interaction: the more (less) cloudiness the ice microphysics produces, the weaker (stronger) the radiative cooling.

The upper-ocean mixing and entrainment of the oceanic deep water play an important role in establishing the quasi-equilibrium SST. The comparison between two coupled and two fixed-SST simulations illustrates that the water vapor variation induced by the change of ice microphysics is reduced by the SST feedback, while the cloud and radiation variation is enhanced in the coupled simulation.

Corresponding author address: Dr. Xiaoqing Wu, NCAR, P.O. Box 3000, Boulder, CO 80307. Email: xiaoqing@ncar.ucar.edu

Abstract

The effects of ice microphysics on the mean state of tropical atmosphere and ocean are quantified using a coupled cloud–ocean model. The cloud-resolving model (CRM) treats explicitly the cloud-scale dynamics instead of using parameterization as is necessary in a general circulation model (GCM). The ocean model is a one-dimensional (1D) mixed layer model with a nonlocal K-profile parameterization to represent the vertical mixing in the oceanic surface boundary layer. Two sets of 40-day simulations attain radiative–convective–oceanic quasi-equilibrium states, one is a coupled simulation, the other has a fixed sea surface temperature (SST). Each set consists of two simulations, with a larger and smaller ice fall speed, respectively.

The two coupled simulations (T0C and M2C) yield dramatically different radiative–convective–oceanic quasi-equilibrium states demonstrating the profound impact of ice microphysics on the water vapor, cloud, and radiation fields. The mean SST and mixed layer depth in M2C is 0.67 K colder and 33 m deeper than those in T0C, and the net surface solar radiation in M2C is 88 W m−2 smaller than that in T0C. The simulation associated with the larger ice fall speed achieves a quasi-equilibrium state characterized by a colder and drier atmosphere, less cloudiness, stronger convection and precipitation, and warmer SST. On the other hand, a quasi-equilibrium state associated with the smaller ice fall speed has a warmer and moister atmosphere, more cloudiness, weaker convection and precipitation, and colder SST. The key mechanism is cloud–radiation interaction: the more (less) cloudiness the ice microphysics produces, the weaker (stronger) the radiative cooling.

The upper-ocean mixing and entrainment of the oceanic deep water play an important role in establishing the quasi-equilibrium SST. The comparison between two coupled and two fixed-SST simulations illustrates that the water vapor variation induced by the change of ice microphysics is reduced by the SST feedback, while the cloud and radiation variation is enhanced in the coupled simulation.

Corresponding author address: Dr. Xiaoqing Wu, NCAR, P.O. Box 3000, Boulder, CO 80307. Email: xiaoqing@ncar.ucar.edu

Save