||Climatological and regional analyses of CASTNet air concentration data /
Eder, B. K. ;
Sickles, J. E.
||Environmental Protection Agency, Research Triangle Park, NC. National Exposure Research Lab. ;National Oceanic and Atmospheric Administration, Research Triangle Park, NC. Atmospheric Sciences Modeling Div.
|| U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory,
Air pollution monitoring ;
Regional analysis ;
Ecological concentration ;
Environmental transport ;
Sulfur dioxide ;
Nitric acid ;
Principal components analysis ;
CASTNet(Clean Air Act Status and Trends Monitoring Network) ;
Clean Air Act Status and Trends Monitoring Network
||Some EPA libraries have a fiche copy filed under the call number shown.
||14 pages : illustrations ; 28 cm
The climatological- and regional-scale variability of ambient air concentrations of SO2, SO4, HNO3, NO3, NH4 and O3 is examined using rotated principal component analysis. This analysis allows the assignment of stations associated with the Clean Air Status and Trends Network (CASTNet) to 'influence regimes' or subregions whose concentrations exhibit statistically unique, homogeneous characteristics. Depending on the species, either two, three, or four subregions were identified by the analysis. An examination of the climatological-scale variability of these homogeneous subregions was then performed using time series analysis techniques including spectral density analysis, which revealed periodicities ranging from weeks to years as well as several possible trends.
"EPA/600/A-98/118." "PB99-102162." Microfiche.