The compilation of measurement based European wet deposition maps of acidifying components and base cations

Precipitation concentrations in 1989 on a European scale were obtained from national organisations responsible for wet deposition monitoring in their countries and from the EMEP database. In total, results from about 750 monitoring locations scattered over Europe were gathered. Spatial analysis based on Regionalised Variable Theory revealed auto-correlation in all ion concentrations and reasonable bounded models were fitted to the experimental variograms. Maps of concentrations of acidifying components and base cations were compiled on a 50×50 km scale using the block-kriging interpolation technique. To obtain fluxes, concentrations were multiplied by long-term mean precipitation amounts from the EPA database. An extensive uncertainty analysis was performed to assess the quality of the maps.