Effect of Aerosol on the Susceptibility and Efficiency of Precipitation in Warm Trade Cumulus Clouds

Hongli Jiang Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, and NOAA/Earth System Research Laboratory, Boulder, Colorado

Search for other papers by Hongli Jiang in
Current site
Google Scholar
PubMed
Close
,
Graham Feingold NOAA/Earth System Research Laboratory, Boulder, Colorado

Search for other papers by Graham Feingold in
Current site
Google Scholar
PubMed
Close
, and
Armin Sorooshian Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona

Search for other papers by Armin Sorooshian in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

Large-eddy simulations of warm, trade wind cumulus clouds are conducted for a range of aerosol conditions with a focus on precipitating clouds. Individual clouds are tracked over the course of their lifetimes. Precipitation rate decreases progressively as aerosol increases. For larger, precipitating clouds, the polluted clouds have longer lifetimes because of precipitation suppression. For clean aerosol conditions, there is good agreement between the average model precipitation rate and that calculated based on observed radar reflectivity Z and precipitation rate R relationships. Precipitation rate can be expressed as a power-law function of liquid water path (LWP) and Nd, to reasonable accuracy. The respective powers for LWP and Nd are of similar magnitude compared to those based on observational studies of stratocumulus clouds. The time-integrated precipitation rate represented by a power-law function of LWP, Nd, and cloud lifetime is much more reliably predicted than is R expressed in terms of LWP and Nd alone. The precipitation susceptibility (So = −dlnR/dlnNd) that quantifies the sensitivity of precipitation to changes in Nd depends strongly on LWP and exhibits nonmonotonic behavior with a maximum at intermediate LWP values. The relationship between So and precipitation efficiency is explored and the importance of including dependence on Nd in the latter is highlighted. The results provide trade cumulus cloud population statistics, as well as relationships between microphysical/macrophysical properties and precipitation, that are amenable for use in larger-scale models.

Corresponding author address: Hongli Jiang, NOAA/Earth System Research Laboratory, 325 Broadway, Boulder, CO 80305. Email: hongli.jiang@noaa.gov

Abstract

Large-eddy simulations of warm, trade wind cumulus clouds are conducted for a range of aerosol conditions with a focus on precipitating clouds. Individual clouds are tracked over the course of their lifetimes. Precipitation rate decreases progressively as aerosol increases. For larger, precipitating clouds, the polluted clouds have longer lifetimes because of precipitation suppression. For clean aerosol conditions, there is good agreement between the average model precipitation rate and that calculated based on observed radar reflectivity Z and precipitation rate R relationships. Precipitation rate can be expressed as a power-law function of liquid water path (LWP) and Nd, to reasonable accuracy. The respective powers for LWP and Nd are of similar magnitude compared to those based on observational studies of stratocumulus clouds. The time-integrated precipitation rate represented by a power-law function of LWP, Nd, and cloud lifetime is much more reliably predicted than is R expressed in terms of LWP and Nd alone. The precipitation susceptibility (So = −dlnR/dlnNd) that quantifies the sensitivity of precipitation to changes in Nd depends strongly on LWP and exhibits nonmonotonic behavior with a maximum at intermediate LWP values. The relationship between So and precipitation efficiency is explored and the importance of including dependence on Nd in the latter is highlighted. The results provide trade cumulus cloud population statistics, as well as relationships between microphysical/macrophysical properties and precipitation, that are amenable for use in larger-scale models.

Corresponding author address: Hongli Jiang, NOAA/Earth System Research Laboratory, 325 Broadway, Boulder, CO 80305. Email: hongli.jiang@noaa.gov

Save
  • Benner, C. T., and J. A. Curry, 1998: Characteristics of small tropical cumulus clouds and their impact on the environment. J. Geophys. Res., 103 , 2875328767.

    • Search Google Scholar
    • Export Citation
  • Berry, E. X., 1968: Modification of the warm rain process. Proc. First Conf. on Weather Modification, Albany, NY, Amer. Meteor. Soc., 81–85.

    • Search Google Scholar
    • Export Citation
  • Bony, S., and J-L. Dufresne, 2005: Marine boundary layer clouds at the heart of tropical cloud feedback uncertainties in climate models. Geophys. Res. Lett., 32 , L20806. doi:10.1029/2005GL023851.

    • Search Google Scholar
    • Export Citation
  • Brenguier, J-L., and R. Wood, 2009: Observational strategies from the micro- to mesoscale. Clouds in the Perturbed Climate System: Their Relationship to Energy Balance, Atmospheric Dynamics, and Precipitation, J. Heintzenberg, and R. J. Charlson, Eds., MIT Press, 487–510.

    • Search Google Scholar
    • Export Citation
  • Cahalan, R. F., and J. H. Joseph, 1989: Fractal statistics of cloud fields. Mon. Wea. Rev., 117 , 261272.

  • Comstock, K. K., R. Wood, S. E. Yuter, and C. S. Bretherton, 2004: Reflectivity and rain rate in and below drizzling stratocumulus. Quart. J. Roy. Meteor. Soc., 130 , 28912918. doi:10.1256/qj.03.187.

    • Search Google Scholar
    • Export Citation
  • Fankhauser, J. C., 1988: Estimates of thunderstorm precipitation efficiency from field measurements in CCOPE. Mon. Wea. Rev., 116 , 663684.

    • Search Google Scholar
    • Export Citation
  • Feingold, G., and H. Siebert, 2009: Cloud-aerosol interactions from the micro to the cloud scale. Clouds in the Perturbed Climate System: Their Relationship to Energy Balance, Atmospheric Dynamics, and Precipitation, J. Heintzenberg and R. J. Charlson, Eds., MIT Press, 319–338.

    • Search Google Scholar
    • Export Citation
  • Feingold, G., S. Tzivion, and Z. Levin, 1988: Evolution of raindrop spectra. Part I: Solution to the stochastic collection/breakup equation using the method of moments. J. Atmos. Sci., 45 , 33873399.

    • Search Google Scholar
    • Export Citation
  • Feingold, G., B. Stevens, W. R. Cotton, and A. S. Frisch, 1996: The relationship between drop in-cloud residence time and drizzle production in numerically simulated stratocumulus clouds. J. Atmos. Sci., 53 , 11081122.

    • Search Google Scholar
    • Export Citation
  • Flossmann, A. I., and H. R. Pruppacher, 1988: A theoretical study of the wet removal of atmospheric pollutants. Part III: The uptake, redistribution, and deposition of (NH4)2SO4 particles by a convective cloud using a two-dimensional cloud dynamics model. J. Atmos. Sci., 45 , 18571871.

    • Search Google Scholar
    • Export Citation
  • Geoffroy, O., J-L. Brenguier, and I. Sandu, 2008: Relationship between drizzle rate, liquid water path and droplet concentration at the scale of a stratocumulus cloud system. Atmos. Chem. Phys., 8 , 46414654.

    • Search Google Scholar
    • Export Citation
  • Hudson, J. G., and S. Mishra, 2007: Relationships between CCN and cloud microphysics variations in clean maritime air. Geophys. Res. Lett., 34 , L16804. doi:10.1029/2007GL030044.

    • Search Google Scholar
    • Export Citation
  • Jiang, H., H. Xue, A. Teller, G. Feingold, and Z. Levin, 2006: Aerosol effects on the lifetime of shallow cumulus. Geophys. Res. Lett., 33 , L14806. doi:10.1029/2006GL026024.

    • Search Google Scholar
    • Export Citation
  • Jiang, H., G. Feingold, and I. Koren, 2009: Effect of aerosol on trade cumulus cloud morphology. J. Geophys. Res., 114 , D11209. doi:10.1029/2009JD011750.

    • Search Google Scholar
    • Export Citation
  • Koren, I., G. Feingold, L. A. Remer, and O. Altaratz, 2008: How small is a small cloud? Atmos. Chem. Phys., 8 , 38553864.

  • Malkus, J. S., 1958: On the structure of the trade wind moist layer. Pap. Phys. Oceanogr. Meteor., 13 , 47.

  • Mechem, D. B., and Y. L. Kogan, 2008: Scaling for precipitation and coalescence scavenging obtained from simulations of trade cumulus. Extended Abstracts, 15th Conf. on Cloud and Precipitation, Cancun, Mexico, ICCP, Poster 4.2.

    • Search Google Scholar
    • Export Citation
  • Mechem, D. B., P. C. Robinson, and Y. L. Kogan, 2006: Processing of cloud condensation nuclei by collision-coalescence in a mesoscale model. J. Geophys. Res., 111 , D18204. doi:10.1029/2006JD007183.

    • Search Google Scholar
    • Export Citation
  • Medeiros, B., B. Stevens, I. M. Held, M. Zhao, D. L. Williamson, J. G. Olson, and C. S. Bretherton, 2008: Aquaplanets, climate sensitivity, and low clouds. J. Climate, 21 , 49744991.

    • Search Google Scholar
    • Export Citation
  • Neggers, R. A. J., H. J. J. Jonker, and A. P. Siebesma, 2003: Size statistics of cumulus cloud populations in large-eddy simulations. J. Atmos. Sci., 60 , 10601074.

    • Search Google Scholar
    • Export Citation
  • Nuijens, L., B. Stevens, and A. P. Siebesma, 2009: The environment of precipitating shallow cumulus convection. J. Atmos. Sci., 66 , 19621979.

    • Search Google Scholar
    • Export Citation
  • Pawlowska, H., and J-L. Brenguier, 2003: An observational study of drizzle formation in stratocumulus clouds for general circulation model (GCM) parameterizations. J. Geophys. Res., 108 , 8630. doi:10.1029/2002JD002679.

    • Search Google Scholar
    • Export Citation
  • Petch, J. C., 2006: Sensitivity studies of developing convection in a cloud-resolving model. Quart. J. Roy. Meteor. Soc., 132 , 345358.

    • Search Google Scholar
    • Export Citation
  • Plank, V. G., 1969: The size distribution of cumulus cloud in representative Florida populations. J. Appl. Meteor., 8 , 4667.

  • Rauber, R. M., N. F. Laird, and H. T. Ochs III, 1996: Precipitation efficiency of trade wind clouds over the north central tropical Pacific Ocean. J. Geophys. Res., 101 , 2624226253.

    • Search Google Scholar
    • Export Citation
  • Rauber, R. M., and Coauthors, 2007: Rain in shallow cumulus over the ocean: The RICO campaign. Bull. Amer. Meteor. Soc., 88 , 19121928.

    • Search Google Scholar
    • Export Citation
  • Seifert, A., and B. Stevens, 2010: Microphysical scaling relations in a kinematic model of isolated shallow cumulus clouds. J. Atmos. Sci., 67 , 15751590.

    • Search Google Scholar
    • Export Citation
  • Short, D. A., and K. Nakamura, 2000: TRMM radar observations of shallow precipitation over the tropical oceans. J. Climate, 13 , 41074124.

    • Search Google Scholar
    • Export Citation
  • Snodgrass, E. R., L. Di Girolamo, and R. M. Rauber, 2009: Precipitation characteristics of trade wind clouds during RICO derived from radar, satellite, and aircraft measurements. J. Appl. Meteor. Climatol., 48 , 464483.

    • Search Google Scholar
    • Export Citation
  • Sorooshian, A., G. Feingold, M. D. Lebsock, H. Jiang, and G. L. Stephens, 2009: On the precipitation susceptibility of clouds to aerosol perturbations. Geophys. Res. Lett., 36 , L13803. doi:10.1029/2009GL038993.

    • Search Google Scholar
    • Export Citation
  • Sorooshian, A., G. Feingold, M. D. Lebsock, H. Jiang, and G. L. Stephens, 2010: Deconstructing the precipitation susceptibility construct: Improving methodology for aerosol-cloud-precipitation studies. J. Geophys. Res., 115 , D17201. doi:10.1029/2009JD013426.

    • Search Google Scholar
    • Export Citation
  • Stevens, B., and A. Seifert, 2008: Understanding macrophysical outcomes of microphysical choices in simulations of shallow cumulus convection. J. Meteor. Soc. Japan, 86A , 143162.

    • Search Google Scholar
    • Export Citation
  • Stevens, B., G. Feingold, W. R. Cotton, and R. L. Walko, 1996: Elements of the microphysical structure of numerically simulated nonprecipitating stratocumulus. J. Atmos. Sci., 53 , 9801006.

    • Search Google Scholar
    • Export Citation
  • Tzivion, S., G. Feingold, and Z. Levin, 1987: An efficient numerical solution to the stochastic collection equation. J. Atmos. Sci., 44 , 31393149.

    • Search Google Scholar
    • Export Citation
  • vanZanten, M. C., B. Stevens, G. Vali, and D. H. Lenschow, 2005: Observations of drizzle in nocturnal marine stratocumulus. J. Atmos. Sci., 62 , 88106.

    • Search Google Scholar
    • Export Citation
  • Wang, H., and G. Feingold, 2009: Modeling mesoscale cellular structure and drizzle in marine stratocumulus. Part I: Impact of drizzle on the formation and evolution of open cells. J. Atmos. Sci., 66 , 32373256.

    • Search Google Scholar
    • Export Citation
  • Warner, J., 1968: A reduction in rainfall associated with smoke from sugar-cane fires—An inadvertent weather modification? J. Appl. Meteor., 7 , 247251.

    • Search Google Scholar
    • Export Citation
  • Wielicki, B. A., and Coauthors, 2002: Evidence for large decadal variability in the tropical mean radiative energy budget. Science, 295 , 841844.

    • Search Google Scholar
    • Export Citation
  • Wood, R., 2006: Rate of loss cloud droplets by coalescence in warm clouds. J. Geophys. Res., 111 , D21205. doi:10.1029/2006JD007553.

  • Wood, R., T. Kubar, and D. Hartmann, 2009: Understanding the importance of microphysics and macrophysics for warm rain in marine low clouds. Part II: Heuristic models of rain formation. J. Atmos. Sci., 66 , 29732990.

    • Search Google Scholar
    • Export Citation
  • Xue, H., and G. Feingold, 2006: Large eddy simulations of trade wind cumuli: Investigation of aerosol indirect effects. J. Atmos. Sci., 63 , 16051622.

    • Search Google Scholar
    • Export Citation
  • Zhao, G., and L. Di Girolamo, 2007: Statistics on the macrophysical properties of trade wind cumuli over the tropical western Atlantic. J. Geophys. Res., 112 , D10204. doi:10.1029/2006JD007371.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 549 85 7
PDF Downloads 333 72 12