Birkenes
Known local emission source areas; Norton industries in Lillesand (15 km SE), Kristiansand city (25 km S/SW). Both are known have minor or even negligible influence on the air quality at the site. Local agricultural activities occasionally yield elevated ammonia concentrations. There has not been major change with respect to the local environment in the vicinity of the site, and it should be considered as a excellent regional sites, well suited for e.g. trend analysis.