EU environmental policies have been built upon scientific findings, and their implementation requires continued monitoring and assessments. Policy evaluations and review, as well as the design of new policy initiatives, require constant updates on the state of the planet. Also, emerging issues may suddenly reach the agenda of decision-makers, who need to be duly prepared to react. The Treaty on the functioning of the European Union foresees that, "in preparing its policy on the environment, the Union shall take account of available scientific and technical data" (art 191).
One of the priority objectives of the 7th EU Environment Action Programme is to ensure that EU policy-makers benefit from credible and updated knowledge for their policy decision. The pace of current developments and uncertainties surrounding likely future trends requires further steps to maintain and strengthen this knowledge and evidence base on environmental monitoring, data, indicators and assessments linked to the implementation of Union legislation, as well as formal scientific research and ‘citizen science’ initiatives. A number of actions are put in place to respond to this challenge: