Forests represent an immense resource, providing a number of ecosystem services from provision of wood and non-wood products, to the protection of biodiversity, provision of habitats, clean water supply, soil protection, climate regulation and recreation essential for human well-being.

Atmospheric pollution with nitrogen and heavy metals as well as ozone formation and climate change may jeopardize the provision of such ecosystem services, and the effects on various forest ecosystem components need to be critically evaluated and permanently monitored.

Since 1985, ICP Forests monitors forest condition and environmental drivers across Europe. The data is used by a large number of scientists investigating various policy relevant research questions.