Paris and its suburbs are burning with anger. Since the death of Nahel, a 17-year-old young driver killed by police fire on Tuesday morning, the flame of spirits is renewed every evening. Violence broke out and street furniture was destroyed and burned. These fires, in schools, town halls, vehicles or police stations, are not without consequences for the quality of the air that Ile-de-France residents breathe.
According Airparif“significant levels of particles (PM10 + PM2.5) were observed in the air”, on the night of June 28 to 29, due “to a large extent to urban clashes”, explains to 20 minutes Pierre Pernot of Airparif. It was not, however, an unprecedented situation, there was no record, but “it was still notable”, he adds.
Favorable weather conditions
The night of the 29th to the 30th, if the urban violence continued in Ile-de-France and elsewhere on the territory, the meteorological conditions were more favorable to the dispersion of the polluting particles. The air quality next night should also be milder with forecasts of wind and especially precipitation overnight in the capital and its suburbs.
“The high concentration of particles is concomitant with a low boundary layer and very high particle emissions”, specifies Pierre Pernot. The boundary layer is “the height of the layer up to which the pollutants will be able to disperse, the higher and therefore wider it is, the greater the dispersion and there is therefore a lower concentration of air pollutants” , he develops.
If the situation then tends to improve for the next night, Airparif will remain vigilant for that of Saturday to Sunday when the conditions will be more unfavorable. But it remains very difficult to predict whether the sequence of events related to Nahel’s death will have an impact on air quality in the future. “It depends on the duration, the scale and under what weather conditions,” recalls Pierre Pernot.