Production of ozone in the Chamonix Valley (France)

Eric Chaxel (1) , Jean-Pierre Chollet (1) , Guillaume Brulfert (1) , Charles Chemel (1)

1 LEGI - Laboratoire des Écoulements Géophysiques et Industriels [Grenoble]

In the framework of the POVA program a numerical investigation aims to better understand how a reduction of traffic emissions can affect air quality in the Chamonix valley (France). The MM5 model coupled with the Chemistry Transport Model (CTM) TAPOM using a 1 km-cell grid for the period 5-12 July 2003 showed that the ozone formation in the Chamonix valley was strongly NOx-saturated. A comparison with physical and chemical measurements (tethered balloon, UHF radar, monitoring data) prove the temperature profile and the up-and downhill thermally-driven winds to be reasonably well described by MM5. Moreover spatial and temporal variation of O 3 concentration is well described by TAPOM. Ozone production within the valley is estimated to 20 to 30 µg/m 3 and 10 µg/m 3 are locally produced from precursors emitted by international traffic through the tunnel.

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Eric Chaxel, Jean-Pierre Chollet, Guillaume Brulfert, Charles Chemel. Production of ozone in the Chamonix Valley (France). International Journal of Environment and Pollution, 2005, 24 (1-2), pp.201-248. ⟨10.1504/IJEP.2005.007394⟩. ⟨hal-00202809⟩