The following considerations for the future design of the EMEP field campaigns emerged from the presentations and the ensuing discussions : `` Intensive Observation Periods '' are important both for science and capacity building in the EMEP framework ; Given the currently lack of data on dry deposition fluxes , vertical profiles of pollutant concentrations , volatile organic compound ( VOCs ) concentrations ( summer situation ) are needed for improving models dedicated to acidification , eutrophication , ozone and PM concentration simulations .