The study of ground ozone concentration levels: a functional analysis approach based on Principal Components Analysis

Ground O3 represents one of the most dangerous environmental pollutants. It is generated through complex physical and chemical processes in the atmosphere and combustion processes in the troposphere involving a non-linear relationship between ozone, other pollutants (in particular its precursor as NO or NO2) and meteorological variables (primarily solar radiation and temperature). Because of this complexity the determination of O3 concentration levels based on a deterministic approach is generally not possible or is limited to a very few particular cases. In this work we have considered an innovative approach based on the application of Functional Principal Components Analysis (FPCA) to experimental data consisting in time series of the concentration of ground O3, NOx, solar irradiation and temperature, in order to extract more or less manifest features characterizing the behaviour of the variables considered, to be used for a better understanding of ground ozone dynamics.