This work was supported fully through the Southeast Regional Center of the National Institute for Global Environmental Change by the U.S. Department of Energy under Cooperative Agreement DE-FC03-90ER61010. Encouragement received from R. Griffin and W. Herz, University of Alabama, is greatly appreciated. We thank B. Daube of Harvard University for help in constructing the size fractionating portion of the cloud water collector; W. P. Robarge and R. Guillermo from the Soil Sciences Laboratory for chemical analyses and the Cloud Physics Group for help in the field experiment. The suggestions from Dr. R. R. Braham and one of the anonymous reviewers are greatly appreciated. BDL would like to thank the U.S. Air Force for providing the opportunity for him to complete his M.S. degree at NCSU.
Bator, A., and J. L. Collett Jr., 1997: Cloud chemistry varies with drop size. J. Geophys. Res.,102, 28 071–28 078.
Carter, E. J., and R. D. Borys, 1993: Aerosol–cloud chemical fractionation: Enrichment factor analysis of cloud water. J. Atmos. Chem.,17, 277–292.
Charlson, R. J., S. E. Schwartz, J. M. Hales, R. D. Cess, J. A. Coakley Jr., J. E. Hansen, and D. J. Hoffmann, 1992: Climate forcing by anthropogenic aerosols. Science,255, 423–430.
Collett, J., Jr., B. Oberholzer, and J. Staehelin, 1993: Cloud chemistry at Mt. Rigi, Switzerland: Dependence on drop size and relationship to precipitation chemistry. Atmos. Environ.,27A, 33–42.
Collett, J., Jr., A. Bator, X. Rao, and B. B. Demoz, 1994: Acidity variations across the cloud drop size spectrum and their influence on rates of atmospheric sulfate production. Geophys. Res. Lett.,21, 2393–2396.
Daum, P. H., 1990: Observations of H2O2 and S(IV) in air, cloud water, and precipitation and their implications for the reactive scavenging of SO2. Atmos. Res.,25, 89–102.
DeFelice, T. P., and V. K. Saxena, 1990a: Temporal and vertical distribution of acidity and ionic composition in clouds: Comparison between modeling results and observations. J. Atmos. Sci.,47, 1117–1126.
DeFelice, T. P., and V. K. Saxena, 1990b: Mechanisms for the operation of three cloudwater collectors: Comparison of mountain-top results. Atmos. Res.,25, 277–292.
DeFelice, T. P., and V. K. Saxena, 1991: The characterization of extreme episodes of wet and dry deposition of pollutants on an above cloud-base forest during its growing season. J. Appl. Meteor.,30, 1548–1561.
DeFelice, T. P., and V. K. Saxena, 1994: On the variation of cloud condensation nuclei in association with cloud systems at a mountain-top location. Atmos. Res.,31, 13–39.
Deininger, C. K., and V. K. Saxena, 1997: A validation of back trajectories of air masses by principal component analysis of ion concentrations in cloud water. Atmos. Environ.,30, 295–300.
Demoz, B. B., J. L. Collett Jr., and B. C. Daube Jr., 1996: On the Caltech active strand cloud water collectors. Atmos. Res.,41, 47–62.
Draxler, R. R., 1991: The accuracy of trajectories during ANATEX calculated using dynamic model analyses versus rawinsonde observations. J. Appl. Meteor.,30, 1446–1447.
Draxler, R. R., 1992: Hybrid single-particle Lagrangian integrated trajectories (HY-SPLIT): Version 3.0. User’s guide and model description. NOAA Tech. Memo. ERL ARL-195, 26 pp.
Easter, R. C., and L. K. Peters, 1994: Binary homogeneous nucleation:Temperature and relative humidity fluctuations, nonlinearity, and aspects of new particle production in the atmosphere. J. Appl. Meteor.,33, 775–784.
Fukuta, N., and V. K. Saxena, 1979a: A horizontal thermal gradient cloud condensation nucleus spectrometer. J. Appl. Meteor.,18, 1352–1362.
Fukuta, N., and V. K. Saxena, 1979b: The principle of a new horizontal thermal gradient cloud condensation nucleus spectrometer. Atmos. Res.,13, 169–188.
Gorham, E., F. B. Martin, and J. T. Litzau, 1984: Acid rain: Ionic correlations in the eastern United States, 1980–81. Science,225, 407–409.
Hegg, D. A., 1990: Heterogeneous production of cloud condensation nuclei in the marine atmosphere. Geophys. Res. Lett.,17, 2165–2168.
Hegg, D. A., 1991: Particle production in clouds. Geophys. Res. Lett.,18, 995–998.
Hegg, D. A., and P. V. Hobbs, 1981: Cloud water chemistry and the production of sulfates in clouds. Atmos. Environ.,15, 1597–1604.
Hegg, D. A., and T. V. Larson, 1990: The effects of microphysical parameterization on model predictions of sulfate production in clouds. Tellus,42B, 272–284.
Hering, S. V., D. L. Blumenthal, R. L. Brewer, A. Gertler, M. Hoffmann, J. A. Kadlecek, and K. Pettus, 1987: Field intercomparison of five types of fogwater collectors. Environ. Sci. Technol.,21, 654–663.
Knollenberg, R. G., 1981: Techniques for probing cloud microstructure. Clouds: Their Formation, Optical Properties, and Effects, P. V. Hobbs and A. Deepak, Eds., Academic Press, 15–91.
Laj, P., and Coauthors, 1998: The size dependent composition of fog droplets. Contrib. Atmos. Phys.,71, 115–130.
Langner, J., H. Rodhe, P. J. Crutzen, and P. Zimmermann, 1992: Anthropogenic influence on the distribution of tropospheric sulfate aerosol. Nature,359, 712–716.
Leaitch, W. R., and G. A. Isaac, 1994: On the relationship between sulfate and cloud drop number concentrations. J. Climate,7, 206–212.
Lelieveld, J., and J. Heintzenberg, 1992: Sulfate cooling effect on climate through in-cloud oxidation of anthropogenic SO2. Science,258, 117–120.
Lin, N.-H., and V. K. Saxena, 1991: In-cloud scavenging and deposition of sulfates and nitrates: Case studies and parameterization. Atmos. Environ.,25A, 2301–2320.
McHenry, J. N., and R. L. Dennis, 1994: The relative importance of oxidation pathways and clouds to atmospheric ambient sulfate production as predicted by the Regional Acid Deposition Model. J. Appl. Meteor.,33, 890–905.
McLaren, S., J. Kadlecek, A. Kadlecek, J. Spencer, and C. Conway, 1985: Field intercomparison of cloud water collectors at Whiteface Mountain: Report from the Whiteface Mountain field station. Atmospheric Sciences Research Center, 66 pp.
Menon, S., and V. K. Saxena, 1998: Role of sulfates in regional cloud–climate interactions. Atmos. Res.,47–48, 299–315.
Millet, M., H. Wortham, and Ph. Mirabel, 1995: Solubility of polyvalent cations in fogwater at an urban site in Strasbourg (France). Atmos. Environ.,29, 2625–2631.
Mueller, S. F., 1994: Characterization of ambient ozone levels in the Great Smoky Mountains National Park. J. Appl. Meteor.,33, 465–472.
Munger, J. W., J. Collett Jr., B. Daube Jr., and M. R. Hoffmann, 1989: Chemical composition of coastal stratus clouds: Dependence on droplet size and distance from the coast. Atmos. Environ.,23, 2305–2320.
Noone, K. J., R. J. Charlson, D. S. Covert, J. A. Ogren, and J. Heintzenberg, 1988: Cloud droplets: Solute concentration is size dependent. J. Geophys. Res.,93, 9477–9482.
Ogawa, N., R. Kikuchi, T. Okamura, T. Adzuhata, M. Kajikawa, and T. Ozeki, 1999: Cloud droplet size dependence of the concentrations of various ions in cloud water at a mountain ridge in northern Japan. Atmos. Res.,51, 77–80.
Ogren, J. A., and R. J. Charlson, 1992: Implications for models and measurements of chemical inhomogeneities among cloud droplets. Tellus,44B, 208–225.
Pruppacher, H. R., and J. D. Klett, 1978: Microphysics of Clouds and Precipitation. D. Reidel, 714 pp.
Radke, L. F., and D. A. Hegg, 1972: The shattering of saline droplets upon crystallization. Atmos. Res.,6, 447–455.
Saxena, V. K., and R. J.-Y. Yeh, 1988: Temporal variability in cloud water acidity: Physico-chemical characteristics of atmospheric aerosols and windfield. J. Aerosol Sci.,19, 1207–1210.
Saxena, V. K., and N.-H. Lin, 1990: Cloud chemistry measurements and estimates of acidic deposition on an above cloudbase coniferous forest. Atmos. Environ.,24A, 329–352.
Saxena, V. K., R. E. Stogner, A. H. Hendler, T. P. DeFelice, R. J.-Y. Yeh, and N.-H. Lin, 1989: Monitoring the chemical climate of the Mt. Mitchell State Park for evaluation of its impact on forest decline. Tellus,41B, 92–109.
Saxena, V. K., P. A. Durkee, S. Menon, J. Anderson, K. L. Burns, and K. E. Nielsen, 1996: Physico-chemical measurements to investigate regional cloud–climate feedback mechanisms. Atmos. Environ.,30, 1573–1579.
Schell, D., and Coauthors, 1997: The size-dependent chemical composition of cloud droplets. Atmos. Environ.,31, 2561–2576.
Seidl, W., 1989: Ionic concentrations and initial S(IV)-oxidation rates in droplets during the condensational stage of cloud. Tellus,41B, 32–50.
Seinfeld, J. H., 1986: Atmospheric Chemistry and Physics of Air Pollution. Wiley Interscience, 738 pp.
Slingo, A., 1990: Sensitivity of the earth’s radiation budget to changes in low clouds. Nature,343, 49–51.
Twohy, C. H., P. H. Austin, and R. J. Charlson, 1989: Chemical consequences of the initial diffusional growth of cloud droplets:A clean marine case. Tellus,41B, 51–60.
Twomey, S., 1974: Pollution and the planetary albedo. Atmos. Environ.,8, 1251–1256.
Twomey, S., 1977: The influence of pollution on the shortwave albedo of clouds. J. Atmos. Sci.,34, 1149–1152.
Twomey, S., 1991: Aerosols, clouds and radiation. Atmos. Environ.,25A, 2435–2442.
Ulman, J. C., and V. K. Saxena, 1997: Impact of air mass histories on the chemical climate of Mount Mitchell, North Carolina. J. Geophys. Res.,102, 25 451–25 465.
Wurzler, S., A. I. Flassmann, H. R. Pruppacher, and S. E. Schwartz, 1995: The scavenging of nitrate by clouds and precipitation. J. Atmos. Chem.,4, 259–280.
Yuen, P.-F., D. A. Hegg, and T. V. Larson, 1994: The effects of in-cloud sulfate production on light-scattering properties of continental aerosol. J. Appl. Meteor.,33, 848–854.