Correlation Analysis among Meteorological Factors and PM10 Concentrations in the Atmosphere and Rainwater Quality using Multivariate Methods

This study investigates the effect of meteorological factors on the concentration of PM₁₀ (particulate matter 10) in the atmosphere and evaluates the variation of chemical quality in rainwater using correlation analysis at Daeyeon dong, Busan, South Korea. The real-time concentration of PM₁₀ in the atmosphere was measured automatically during eleven rainfall events with a custom-built PM₁₀ sensor node. The 183 rainfall samples were analyzed for chemical quality (pH and electrical conductivity (EC)). The values of meteorological factors (humidity, wind speed, wind direction, temperature, cumulative rainfall, and rainfall intensity) were obtained from an automatic weather system (AWS) in Nam-gu, Busan. Pearson correlation analysis and principal component analysis (PCA) were performed to identify relationships among PM₁₀ concentrations, meteorological factors, and chemical quality in rainwater. Cumulative rainfall and rainfall intensity had negative correlations with the concentration of PM₁₀ (r =  −0.52, and −0.35), and other meteorological factors were shown no correlation with the concentration of PM₁₀. When the rainfall intensity was strong (> 5 mm/h), the concentration of PM₁₀ showed a negative correlation with the cumulative rainfall (r = −0.55) and pH (r = −0.7). However, for the weak rainfall intensity (< 5 mm/h), there was no correlation between the PM₁₀ concentration with cumulative rainfall and pH. The results of this study provide an understanding of the interaction between PM₁₀ concentrations and hydro-meteorological factors and can be used as a decision tool to evaluate the relative magnitude of PM₁₀ reduction resulting from various rainfall types.