Aerosol particles are an important constituent of the atmospheric system. Particles
may be created as primary aerosol particles - those that are released directly into
the atmosphere as particulate matter or as secondary aerosols - those formed during
gas-to-particle conversion of gaseous precursors emitted into the atmosphere. Particles
are emitted from both natural and anthropogenic activities. Sources vary from
widespread surface sources like deserts and arid surfaces (mineral soil dust), oceans
(sea-salt), biosphere (pollen, bacteria, plant debris) and biomass and fuel burning
(organic and graphitic carbon, fly ash). Industries and diffuse sources like traffic
emit mainly carbonaceous aerosols and secondary gaseous precursors, while intense
point sources, e.g., volcanic eruptions, inject large volumes of particles and traces
gases into the atmosphere. Extraterrestrial sources are usually negligible. The major
gaseous precursors are sulphur dioxide (SO2), ammonia (NH3), oxides of nitrogen
(NOx), dimethyl sulphide (DMS) and volatile organic compounds (VOCs). Estimates
for global source strengths of particles and their precursors can be found elsewhere
(IPCC, 2001). [...]
Patience Gwaze
Aerosol particles Chemical properties Microscopy methods Physical properties