Air-Temperature Dependence of the Ozone Generation Rate in the Surface Air Layer

Abstract

The temperature dependence of the atmospheric ozone generation rate was studied based on measurements in a reference area. The type of this dependence is determined by the method based on the comparison of variations in the ozone concentration when a hot or cold wave passes above the measurement post. This approach allowed us to derive for the first time the quantitative, but not qualitative, dependence type. The coefficients of the expression used depend on both the air temperature and initial ozone concentration. Thus, at the long-term minimum of the surface ozone concentration (1999) at a temperature of 30°C, its increase of 5 μg/m³ corresponded to a temperature change of 1°C. At a maximal concentration (2001) and the same temperature, the increase is almost 25 μg/m³ per 1°C. In the intermediate periods (1997 and 2010), it was about 14 μg/m³ per 1°C. The analysis shows that the quadratic character of the given dependence is conditioned by the nonlinear increase in reaction constants and the quadratic increase in hydrocarbon emissions by vegetation with increasing air temperature.