Diurnal and seasonal variation of the surface ozone in Spain

In this study we present the diurnal and monthly variations in the surface ozone concentrations of five Spanish remote stations belonging to the EMEP network. In two of the stations, a maximum in the afternoon is presented because of the turbulent mixing producing appreciable downward ozone flux. In other two stations no maxima are produced. In one of them this result is due to the strong westerly winds that dominate the air flow and the low solar insolation. In the other station the reason are two phenomena: the mountain induced flow regime that produce high concentrations during the night and the photochemical production that results in high concentrations during the afternoon.