The air quality in the canton of Obwalden

The canton Obwalden mainly consists of two alpine valleys in Switzerland. Since measurements show that ozone limits in this region are regularly exceeded, the authorities of the canton decided to carry out a scientific project. The project investigated where the pollutants came from, and how they were transported into the valley. The mountain valley wind systems were investigated.

	This map shows the topography, the modeling domains and the measurement sites of the project.
	The final report (in German...) includes a detailed description of measurement and model results.
	The view the temporal evolution of ozone and winds, you can look at this MPEG-video (9.3 MB!). (For information about MPEG see here, for example)
	Download the result files in vid5D-format and investigate it with the vis5d software.