Chem541 Atmospheric ChemistryAerosols

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Outline

Definition Environmental and health effects of Aerosols Aerosol size Air quality and aerosols Aerosol sources Typical tropospheric aerosol residence time Processes for aerosol production, growth, and removal Typical chemical composition of atmospheric aerosols Radiative effects of aerosolsScattering of radiation by aerosols Visibility reduction Optical depth Perturbation to climate by aerosolsLight scattering Indirect forcing2

Definitions Aerosol is a suspension of solid or liquid particles in a gas. Atmospheric aerosols consist of small particles of liquid and solid material suspended in the air. Bioaerosol: An aerosol of biological origin. (Examples: viruses, bacteria, fungi, spores, and pollens.) Aerosol sizes are usually measured in the unit of micrometer (m) 1 m = 106 m 1 m = 104 angstrom () Fine particles (1 m) Respirable suspended particulate matter or RSP (