Record Display for the EPA National Library Catalog


Main Title Principal Component Analysis of SO4(2-) Precipitation Concentrations over the Eastern United States.
Author Eder., B. K. ;
CORP Author Environmental Protection Agency, Research Triangle Park, NC. Atmospheric Research and Exposure Assessment Lab.
Publisher c1989
Year Published 1989
Report Number EPA/600/J-89/344;
Stock Number PB90-216094
Additional Subjects Sulfates ; Precipitation(Chemistry) ; Factor analysis ; Atmospheric models ; Deposition ; Precipitation(Meteorology) ; Concentration(Composition) ; Mathematical models ; Sulfur oxides ; Spatial distribution ; Seasonal variations ; Time series analysis ; Reprints ; Eastern Region(United States) ; Air pollution sampling ; Acid rain ; Temporal distribution ; Regional analysis
Library Call Number Additional Info Location Last
NTIS  PB90-216094 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 14p
The spatial and temporal variability of SO4(-2) concentrations in precipitation over the eastern United States during the period 1981-1986 was examined through the use of principal component analysis. Application of Kaiser's Varimax orthogonal rotation led to the delineation of seven contiguous subregions, each displaying statistically unique SO4(-2) concentration characteristics. These seven statistically significant modes of variability, which together accounted for 74.2% of the total variance, corresponded well with major SOx emission patterns. Examination of the time series associated with subregion revealed a general seasonality in which periods of high concentrations are more likely during the summer, while periods of low concentrations are more likely during the winter. This seasonal cycle, however, was more prevalent in those subregions which contained few major emissions, and was less prevalent and often obscured by perturbations in those subregions which contained major emissions.