counts from those simultaneously measured upwind, with typical
increases of a few hundred . Such differences
were within the range of normally observed fluctuations in atmospheric
ion concentrations.
D. Aerosol Concentrations
The range of annual mean aerosol concentrations was
4,000–9,000 condensation at the North
Site and 11 000–18 000 at the South Site. These levels
are consistent with the rural and suburban locales of the sites.