The MAP3S/RAINE precipitation chemistry network: Statistical overview for the period 1976

The MAP3S/RAINE precipitation chemistry network: Statistical overview for the period 1976–1980

Abstract This paper presents a basic statistical summary of the initial $3 built1 2$ year operating period of the MAP3S/RAINE precipitation chemistry network. The overview considers statistical features of the precipitation event data base, including temporal and variable-pair behavior and spatial (site-to-site) relationships. Seasonal variations in concentrations of the species total sulfur. SO2, free hydrogen ion and NH4 ⁺ are easily identifiable from both event and monthly average time trend analyses. Species-pair correlations are generally strong and positive among the major ionic species total S, nitrate, free hydrogen and ammonium; variations from this trend at individual sites can be related to geographical location. Though reasonable coherency is exhibited in site-to-site correlation analyses, the questions of proper averaging time and network density make interpretation of spatial statistics difficult. It is anticipated that this summary will be a directly useful resource for wet-deposition assessment in the northeastern United States, and should compose a convenient starting point for more detailed analysis by the extended research community.