Sea salt nuclei

Metnieks, A. L., 1958 The size spectrum of large and giant sea-salt nuclei under maritime conditions. Geophys. Bulletin 15, 1-50. 

Very small, solid particles include carbon black, silver iodide, combustion nuclei, and sea-salt nuclei formed by the loss of water from droplets of seawater. Larger particles include cement dust, wind-blown soil dust, foundry dust, and pulverized coal. Liquid particulate matter, mist, includes raindrops, fog, and sulfuric acid droplets. Some particles are of biological origin, such as viruses, bacteria, bacterial spores, fungal spores, and pollen. Particulate matter may be organic or inorganic both types are very important atmospheric contaminants. 

Miller, D. F D. Lamb, and A. W. Gertler, S02 Oxidation in Cloud Drops Containing NaCI or Sea Salt as Condensation Nuclei, Atmos. Environ., 21, 991-993 (1987). 

Novakov and Penner (1993) measured the mass size distributions of sulfur, organic carbon, and chlorine (characteristic of sea salt) as well as the CCN concentration (at 0.5% supersaturation), nss, and Aitken nuclei concentrations at a mountain peak in Puerto Rico. 

O Dowd, C. D., J. A. Lowe, and M. H. Smith, Biogenic Sulphur Emissions and Inferred Non-Sea-Salt-Sulphate Cloud Condensation Nuclei in and around Antarctica, J. Geophys. Res., 102, 12839-12854 (1997a). 

Particles ranging from aggregates of a few molecules to pieces of dust readily visible to the naked eye are commonly found in the atmosphere. Some of these particles, such as sea salt formed by the evaporation of water from droplets of sea spray, are natural and even beneficial atmospheric constituents. Very small particles called condensation nuclei serve as bodies for atmospheric water vapor to condense upon and are essential for the formation of precipitation. 

Mason B. J. (2001) The role of sea-salt particles as cloud condensation nuclei over the remote oceans. Q. J. R. Meteorol. Soc. 127, 2023 -2032. 

Source mechanisms are the main subject of this section. We describe the production of mineral dust, sea salt, and condensation nuclei, then present estimates of global production rates. 

Radke, L. F. (1981). Marine aerosol simultaneous size distributions of the total aerosol and the sea-salt fraction from 0.1 to 10 pm diameter. Proc. Int. Conf. Atmos. Aerosol, Condensation, Ice Nuclei, 9th, Galway, Ireland (A. F. Roddy and T. C. O Connor, eds.), pp. 487-491. 

The sources and chemical compositions of the fine and coarse particles are different. Coarse particles are generated by mechanical processes and consist of soil dust, sea salt, fly ash, tire wear particles, and so on. Nuclei and accumulation mode particles contain primary particles from combustion sources and secondary aerosol material (sulfate, nitrate, ammonium, secondary organics) formed by chemical reactions resulting in gas-to-particle conversion (see Chapters 9 and 13). 

Sea-salt aerosol (SSA) has multiple impacts (beside other particulate matter categories) on atmospheric properties response to climate by optical properties (e. g., Mahowald et al. 2006) providing cloud condensation nuclei (e. g., Clarke et al. 2006) being a heterogeneous surface for multiphase chemical reactions, e. g., SO2 oxidation (Luria and Sievering 1991) and a source for reactive chlorine (e. g., Fin-... 

Recently, several articles have appeared on the combined use of different other microanalysis techniques for atmospheric aerosols. Let us mention one. Hopkins et al. successfully used CC SEM/EDX, time-of-flight secondary ion mass spectrometry (TOF-SIMS) and scanning transmission X-ray microscopy/near-edge X-ray absorption fine structure analysis (STXM/NEXAFS) to study quantitatively methanesulphonate (CHsSOs") and non-sea salt sulphate in individual marine aerosol particles. This indicated e.g. that CHsSOs" salts were the dominant source of non-seasalt sulphur in large particles, while sulphate was more common in smaller particles. Quantitative assessment of these two forms is important for kinetic modelling concerning the pathways of natural dimethylsulphide oxidation and the impact on the number and size of cloud condensation nuclei in the marine environment. 

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