Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 1 2007 10.5194/acpd-7-3203-2007 http://www.atmos-chem-phys-discuss.net/7/3203/2007/ http://www.atmos-chem-phys-discuss.net/7/3203/2007/acpd-7-3203-2007.html http://www.atmos-chem-phys-discuss.net/7/3203/2007/acpd-7-3203-2007.pdf 3203 3228 2007-02-27 Long-range transport of mineral aerosols and its absorbing and heating effects on cloud and precipitation: a numerical study Y. Yin yyatnuist@yahoo.co.uk L. Chen Nanjing University of Information Science and Technology, Nanjing 210044, China There have been numerous recent publications showing that mineral dust might be a good absorber for solar radiation in addition to its capability as cloud condensation nuclei (CCN) and ice forming nuclei (IFN), and could lead to reduced cloud cover and precipitation in the region it presents. This effect is investigated using a cloud model with detailed microphysics of both warm and ice phase processes. The model is initialized using measured distributions and concentration of mineral dust particles. Our results show that when the dust layer with peak concentration appears at the cloud-base height and below 3 km, where the temperature is warmer than –5°C, inhibits the development of cloud particles and precipitation, and together with early activation of larger cloud droplets on giant cloud condensation nuclei, which accelerates drizzle formation through collision coalescence process, reduces the cloud optical depth and albedo. It is also found that only when the dust layer locates at altitudes with temperature colder than –5°C, mineral aerosols can act as effective ice nuclei and intensify the ice-forming processes. Under this condition, the existence of dust layer can either increase or decrease cloud optical depth and albedo, depending on the concentration and chemical composition of the absorbing components, or the time the mineral aerosols suspended in the atmosphere. Andreae, M. O., Charlson, R. J., Bruynseels, F., Storms, H., van Grieken, R., and Maenhaut, W.: Internal mixtures of sea salt, silicates and excess sulfate in marine aerosols, Science, 232, 1620–1623, 1986. Cheng, T. and Shen, Z.: The radiative forcing of atmospheric dust in northwest China, Plateau Meteorology, 21(5), 473–478, 2002. Cooper, W. A. and Lawson, R. P.: Physical interpretation of results from the HIPLEX-1 experiment, J. Climate Appl. Meteorol., 23, 523–540, 1984. Costa, M. J., Sohn, B. J. , Levizzani, V., and Silva, A. M.: Radiative forcing of Asian dust determined from the synergized GOME and GMS satellite data – A case study, J. Meteorol. Soc. Jpn., 84, 85–95, 2006. DeMott, P. J., Sassen, K., Poellot, M. R., et al.: African dust aerosols as atmospheric ice nuclei, Geophys. Res. Lett., 30(14), 1732, doi:10.1029/2003GL017410, 2003. Huang, J., Minnis, P., Lin, B., et al.: Possible influences of Asian dust aerosols on cloud properties and radiative forcing observed from MODIS and CERES, Geophys. Res. Lett., 33, L06824, doi:10.1029/2005GL024724, 2006a. Huang, J., Lin, B., Minnis, P., et al.: Satellite-based assessment of possible dust aerosols semi-direct effect on cloud water path over East Asia, Geophys. Res. Lett., 33, L19802, doi:10.1029/2006GL026561, 2006b. Intergovernmental Panel on Climate Change (IPCC), World Meteorological Office, United Nations Environmental Programme, 2001: Summary for Policymakers. Jaenicke, R.: Aerosol physics and chemistry, in Ladolt-Boernstein: Zahlenwerte und Funktionen aus Naturwissenschaften und Technik, vol. 4b, edited by: Fischer G., 391– 457, Springer-Verlag, New York, 1988. Krauss, T. W., Bruintjes, R. T., Verlinde, J., and Kahn, A.: Microphysical and radar observations of seeded and unseeded continental cumulus clouds, J. Climate Appl. Meteorol., 26, 585–606, 1987. Levin, Z., Ganor, E., and Gladstein, V.: The effects of desert particles coated with sulfate on rain formation in the eastern Mediterranean, J. Appl. Meteorol., 35, 1511–1523, 1996. Levin, Z., Teller, A., Ganor, E., and Yin, Y.: On the interactions of mineral dust, sea salt particles and clouds – Measurements and modeling study from the MEIDEX campaign, J. Geophys. Res, 110, D20202, doi:10.1029/2005JD005810, 2005. Lohmann, U. and Diehl, K.: Sensitivity Studies of the Importance of Dust Ice Nuclei for the Indirect Aerosol Effect on Stratiform Mixed-Phase Clouds, J. Atmos. Sci, 63, 968–982, 2006. Niu, S., Zhang, C., and Sun, J.: A observational study of the particle spectra of dust aerosol over the Helan Mts. Region, Chinese J. Atmos. Sci., 25(2), 243–252, 2001. Prospero, J. M.: Long range transport of mineral dust in the global atmosphere: Impact of African dust on the environment of the southeastern United States, Proc. Nat. Acad. Sci., 96, 3396–3403, 1999. Pruppacher, H. R. and Klett, J. D.: Microphysics of Clouds and Precipitation, D.Reidel, 714pp, 1997. Reisin, T., Levin, Z., and Tzivion, S.: Rain production in convective clouds as simulated in an axisymmetric model with detailed microphysics. Part I: Description of the model, J. Atmos. Sci., 53, 497–519, 1996. Rosenfeld, D., Rudich, Y., and Lahav, R.: Desert dust suppressing precipitation: A possible desertification feedback loop, Proc. Natl. Acad. Sci. U. S. A., 98(11), 5975–5980, 2001. Rudich ,Y., Khersonsky, O., and Rosenfeld, D.: Treating clouds with a grain of salt, Geophys. Res. Lett., 29(22), 2060, doi:10.1029/2002GL016055, 2002. Trochkine D., Iwasaka, Y., Matsuki, A., et al.: Mineral aerosol particles collected in Dunhuang, China, and their comparison with chemically modified particles collected over Japan, J. Geophys. Res., 108(D23), 8642, doi:10.1029/2002JD003268, 2003. Tzivion, S., Feingold, G., and Levin, Z.: A efficient numerical solution to the stochastic collection equation, J. Atmos. Sci., 44, 3139–3149, 1987. Tzivion, S., Feingold, G., and Levin, Z.: The evolution of raindrop spectra. Part II: Collisional collection/breakup and evaporation in a rainshaft, J. Atmos. Sci., 46, 3312–3327, 1989. Tzivion, S., Reisin, T., and Levin, Z.: A numerical solution of the kinetic collection equation using high spectral grid resolution: A proposed reference, J. Comput. Phys., 148, 527–544, 1999. Wurzler, S., Reisin, T. G., and Levin, Z.: Modification of mineral dust particles by cloud processing and subsequent effects on drop size distributions, J. Geophys. Res., 105(D4), 4501–4512, 2000. Yin, Y., Levin, Z., Reisin, T. G., et al.: The effect of giant cloud condensation nuclei on the development of precipitation in convective clouds – A numerical study, Atmos. Res., 53, 91–116, 2000. Yin, Y., Wurzler, S., Levin, Z. et al.: Effects on precipitation and cloud optical properties, J. Geophys. Res., 107(D23), 4724, doi:10.1029/2001JD001544, 2002. Zhang, X. Y., Gong, S. L., Shen, Z. X., et al.: Characterization of soil dust aerosol in China and its transport and distribution during 2001 ACE-Asia: 1. Network observations, J. Geophys. Res., 108(D9), 4261, doi:10.1029/2002JD002632, 2003. Zhao, T. L., Gong, S. L., Zhang, X. Y., and McKendry, I. G.: Modeled size-segregated wet and dry deposition budgets of soil dust aerosol during ACE-Asia 2001: Implications for trans-Pacific transport, J. Geophys. Res., 108(D23), 8665, doi:10.1029/2002JD003363, 2003.