CO 2 -TEA mid-infrared laser-based DIAL system: featuring urban atmosphere ozone dynamics during a vehicle-free day

Abstract

Long-path ozone integrated measurements with a CO 2 -laser DIAL system were performed in Madrid City during the "vehicle-free" day. The results showed a strong correlation between human activity and ozone photochemical generation. The ozone concentration follows, even quantitatively, the same trend of the overall traffic intensity as long as both the UVB radiation and NO 2 are present. An average decrease of 12.3 ± 1.2 % of the intensity of vehicle traffic during the "free-vehicle" day resulted in a lowering the ozone burden by almost 14.4 ± 1.4 % . This new type of information can stimulate the development of local models to understand the dynamic underlying urban pollution. The results indeed show the effectiveness of such a measure as to reduce the ozone burden on human and plants health.