Clean Air Status and Trends Network (CASTNET) Weekly Ambient Concentrations
Weekly average air concentrations from CASTNET filter pack data in standard Tuesday 9:00 AM - Tuesday 8:00 AM weeks. The data are collected using an open face, 3-stage filter pack. Data include aerosol concentrations of sulfate, nitrate, ammonium, calcium, sodium, potassium, magnesium and chloride and gaseous …