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SONTAS field study took place June 19-July 19, 2000, at two sites; an urban site in downtown Hamilton and a rural site near Simcoe about 70 km southwest of Hamilton close to Lake Erie.  Both sites coexisted with Ontario Ministry of the Environment monitoring stations where supplemental data was available. The purpose of the study was to learn more about the sources and formation mechanisms of atmospheric aerosols, small particles of either liquid or solid content suspended in air, ranging in diameter from a few nanometers to a few tens of micrometers. Atmospheric aerosols are known to have adverse human health effects, especially those particles of inhalable (ring summer, residents in Southern Ontario experience some of the worst air quality episodes in Canada, partially due to local emissions and partially due to transport of ozone, PM2.5 and their precursors from other regions southwest of the domain.  Click for more information

Updated on August 24th, 2016.