end of red vigilance for fine particles in the Arve valley

The episode of fine particle pollution ended this Thursday in the Arve valley, in Haute-Savoie. Conditions will improve further in the coming days, favoring the dispersion of pollutants.

The alert is lifted in the Arve valley, placed on red alert since Sunday due toan episode of air pollution. Vigilance was lifted in the afternoon this Thursday, January 2, announced the Haute-Savoie prefecture.

“The arrival of the southerly wind should ensure more dispersive conditions. The situation will therefore improve from (this Thursday) and for the next few days“details Atmo Auvergne-Rhône-Alpes in its latest bulletin.

During the pollution peak, several restrictions were put in place such as the ban on using individual wood heaters for supplementary or pleasure use, the reduction of the heating temperature of buildings to 18°C ​​or even the lowering speeds on the roads. These are now lifted.

Friday, “the wind will shift from south to north direction and will remain strong, favoring the dispersion of pollutants”predicts Atmo while the improvement in the situation should become widespread on Saturday in the region.

The Arve valley, which extends from Chamonix to the limits of the Pays Rochois, was the subject of an episode of “combustion” type air pollution. Sandwiched between two massifs, it is particularly vulnerable to the phenomenon known as “temperature inversion”, when cold air remains blocked under warmer air, which forms a “lid” preventing pollutants from dispersing at altitude.

Since Saturday, fine particles known as PM10 (attributable to wood fireplaces, exhaust gases, industrial or agricultural discharges, etc.) had therefore reached alarming levels in the valley.

Tags France