Particulates

Cloud condensation nuclei or CCNs are small particles (typically 0.00002 mm, or 1/100 th the size of a cloud droplet ** ) about which cloud droplets coalesce. Water requires a solid surface to make the transition from a vapour to a liquid. In the atmosphere, this surface presents itself as tiny solid particles called CCNs. When no CCNs are present, water vapour can be supercooled below 0 ° C (32 ° F) before droplets spontaneously form (this is the basis of the cloud chamber for detecting subatomic particles). ...more on Wikipedia about "Cloud condensation nuclei"

Condensation can be summarized as a phase transition from gas to liquid as vapor condenses on a pre-existing surface, in the other way a transition from liquid to vapor in the case of evaporation. Both condensation and evaporation happen in the same time, the balance in between both determine which of them dominates. When the vapor is condensing, the particles on which the vapor condensate will grow bigger, in the same way when vapor evaporates from a particle, it will shrink. This can be seen in the size distribution of aerosol. When the vapor is condensing, then the size distribution moves to bigger sizes, on the contrary, when the vapor is evaporating it moves towards smaller sizes. As the size distribution grows towards bigger or smaller sizes, the airborne mass concentration increases or decreases respectively. In atmosphere, condensation by, for example H2SO4 and organic compounds, is the main growth mechanism. ...more on Wikipedia about "Condensation in aerosol dynamics"

Deposition is a process where aerosol particles set down onto surfaces. It can be divided into two sub-processes, dry and wet deposition. ...more on Wikipedia about "Deposition (Aerosol physics)"

Particulates, alternately referred to as Particulate Matter (PM), aerosols or fine particles are tiny particles of ...more on Wikipedia about "Particulate"

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