The Open Atmospheric Science Journal

2012, 6 : 19-32
Published online 2012 February 06. DOI: 10.2174/1874282301206010019
Publisher ID: TOASCJ-6-19

Relations Between Bulk Precipitation, PM10 Composition and Meteorological Conditions in the Metropolitan Area of Costa Rica

Jorge Herrera Murillo , Susana Rodriguez , Jose Felix Rojas and Armando Baez
Laboratorio de Analisis Ambiental, Escuela de Ciencias Ambientales, Universidad Nacional. Campus Omar Dengo, Heredia, Costa Rica.

ABSTRACT

Concentrations of inorganic ions (Cl-, H+, SO42-, NO3-, NH4+, Na+, K+, Ca2+, Mg2+) and metals (V, Ni, Cu, Pb, Cr Mn, Al, Fe) in bulk precipitation and PM10 samples collected in the metropolitan area of Costa Rica were analyzed. Good correlations between acidity in bulk precipitation with the concentrations of aerosols in the air were observed. The scavenging of the pollutants from the air directly affects the pH and composition of the bulk precipitation. The major ions in bulk precipitation in the metropolitan area of Costa Rica were SO42-, NH4+, Ca2+, Na+ ion percentages with 41.4, 12.0, 10.9 and 9.1 respectively. Al, Fe and Mn were the most abundant trace metals. The alkaline cations, NH4+ and Ca2+, actedas acid neutralizers and buffered the acidity of bulk precipitation. Meteorological conditions presented during the events determine the composition of bulk precipitation samples.