Liquid water clouds

Schwartz, S. E. Gas-Aqueous Reactions of Sulfur and Nitrogen Oxides in Liquid Water Clouds, in S02, NO, and N02 Oxidation Mechanisms. Atmospheric Considerations (J. G. Calvert, Ed.), pp. 173-208 and references therein, Acid Precipitation Series, Vol. 3 (J. I. Teasley, Series Ed.), Butterworth, Stoneham, MA, 1984a. 

Schwartz, S. E., Mass-Transport Considerations Pertinent to Aqueous Phase Reactions of Gases in Liquid-Water Clouds, NATO AS1 Series, G6, 416-471 (1986), and in Chemistry of Multiphase Atmospheric Systems (W. Jaeschke, Ed.), pp. 415-471, Springer-Verlag, New York, 1986. 

Schwartz, S. E., Gas- and Aqueous-Phase Chemistry of H02 in Liquid Water Clouds, J. Geophys. Res., 89, 11589-11598 (1984b). 

Han, Q., W. B. Rossow, and A. A. Lacis, Near-Global Survey of Effective Droplet Radii in Liquid Water Clouds Using ISCCP Data, J. Clim., 7, 465-497 (1994). 

The composition of liquid-water clouds and processes responsible for this composition are of obvious current interest in conjunction with the so-called acid precipitation phenomenon since clouds constitute the immediate precursor of precipitation. Additionally, cloud composition is of interest because impaction of cloud droplets on surfaces may directly deliver dissolved substances onto natural or artificial materials. In-cloud processes also influence clear-air composition since dissolved substances resulting from such reactions are released into clear air as gases or aerosol particles upon cloud evaporation. It is thus desired to gain enhanced description of the composition of clouds and the mecha-... 

Liquid-water clouds (5) represent a potentially important medium for atmospheric chemical reactions in view of their high liquid water content [104 to 105 times that associated with clear-air aerosol (6)] and high state of dispersion (typical drop radius 10 pm). Clouds are quite prevalent in the atmosphere (fractional global coverage 50%) and persistent (lifetimes of a few tenths of an hour to several hours). The presence of liquid water also contributes to thermochemical driving force for production of the highly soluble sulfuric and nitric acids. 

Schwartz, S. E. Mass-transport considerations pertinent to aqueous-phase reactions of gases in liquid-water clouds. In Chemistry of Multiphase Atmospheric Systems Jaeschke, W.,... 

In the case of high liquid water clouds, the D(X) value can be as high as 10 as noted by Madronich [109,110] and co-workers. For example, they note that measurements of spectral ultraviolet-B irradiance under optically thick clouds show strongly enhanced attenuation by molecular and particulate absorbers and that the photon path is enhanced due to the presence of the highly scattering medium, leading to an amplification of absorption by chromophores. Using discrete ordinate and Monte Carlo model caculations, they [110] showed that photon paths (i.e., D(X)) in realistic water clouds could be enhanced by factors of 10 and more compared to cloudless sky. ... 

Processes similar to those in liquid-water clouds govern the formation of ice particles from water vapor, except that only a limited subset of aerosol particles are effective at nucleating ice particles (ice-forming nuclei, IFN Demott, 2002). For this process to occur, there must be a match between the crystal structure of the particle nucleus and that of ice. Liquid-water clouds commonly form well below 0 °C because of the abundance of CCN and the paucity of IFN, despite the formation of ice particles being thermodynamically favored (Demott, 2002). 

Schwartz, S. E. (1984) "Gas-Aqueous Reactions of Sulfur and Nitrogen Oxides in Liquid-Water Clouds," Acid Precipitation edited by J. G. Calvert, Butterworth PublTsliers, Boston, MA. 

Wameck, P. (1985). The equilibrium distribution of atmospheric gases between the two phases of liquid water clouds. In Multiphase Atmospheric Chemistry (W. Jaeschke, ed.), pp. 473-499. NATO ASI Series, Vol. G6, Springer-Verlag, Berlin and New York. Wasserburg, G. J., E. Mazor, and R. E. Zartman (1963). Isotopic and chemical composition of some terrestrial natural gases. In Earth Science and Meteorites" (J. Geis and E. D. Goldberg, eds.), pp. 219-240. 

Ten Brink, H. M., Schwartz, S. E., and Daum, P. H. (1987) Efficient scavenging of aerosol sulfate by liquid water clouds, Atmos. Environ. 21, 2035-2052. 

Han. Q., Rossow, W. B., and Lacis, A. A. (1994) Near-global survey of effective droplet radii in liquid water clouds using ISCCP data, J. Climate, 7, 465 97. 

S. E. Schwartz, Gas-aqueous reactions of sulfur and nitrogen oxides in liquid-water clouds, in SO2, NO, and NO2 Oxidation Mechanisms Atmospheric Considerations 0. G. Calvert ed.), Butterworth, Woburn, MA, 1984, p. 173. 

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