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    Do new sea spray aerosol source functions improve the results of a regional aerosol model?
    (Amsterdam [u.a.] : Elsevier Science, 2018) Barthel, Stefan; Tegen, Ina; Wolke, Ralf
    Sea spray aerosol particle is a dominating part of the global aerosol mass load of natural origin. Thus, it strongly influences the atmospheric radiation balance and cloud properties especially over the oceans. Uncertainties of the estimated climate impacts by this aerosol type are partly caused by the uncertainties in the particle size dependent emission fluxes of sea spray aerosol particle. We present simulations with a regional aerosol transport model system in two domains, for three months and compared the model results to measurements at four stations using various sea spray aerosol particle source source functions. Despite these limitations we found the results using different source functions are within the range of most model uncertainties. Especially the model's ability to produce realistic wind speeds is crucial. Furthermore, the model results are more affected by a function correcting the emission flux for the effect of the sea surface temperature than by the use of different source functions. © 2018 The Authors
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    Chemical composition of cloud water in the puerto rican tropical trade wind cumuli
    (Dordrecht : Springer, 2009) Gioda, A.; Mayol-Bracero, O.L.; Morales-García, F.; Collett, J.; Decesari, S.; Emblico, L.; Facchini, M.C.; Morales-De Jesús, R.J.; Mertes, S.; Borrmann, S.; Walter, S.; Schneider, J.
    As part of the Rain In Cumulus over the Ocean Experiment (RICO) and the Puerto Rico Aerosol and Cloud Study (PRACS), cloud water was collected at East Peak (EP) in Puerto Rico. The main objective of this study was to determine the concentrations of water-soluble species (Cl-, NO3 -, SO4 2-, NH4 +, Ca 2+, H+, Mg2+, K+, and Na +) in water samples taken from clouds influenced by tropical trade winds. The most abundant inorganic species were Na+ (average 465 μeq l-1) and Cl- (434 μeq l-1), followed by Mg2+ (105 μeq l-1), SO4 2- (61 μeq l-1), and NO3 - (25 μeq l -1). High concentrations of nss-SO4 2 (28 μeq l-1), NO3 - (86 μeq l-1), and H+ (14.5 μeq l-1) were measured with a shift in air masses origin from the North Atlantic to North American continent, which reflected a strong anthropogenic influence on cloud chemistry at EP. Long-range transport of particles and acid gases seems to be the factor responsible for fluctuations in concentrations and pH of cloud water at East Peak. When under trade wind influences the liquid phase concentrations of all inorganic substances were similar to those found in clouds in other clean maritime environments. © 2008 Springer Science+Business Media B.V.