Critical loads of acidity to surface waters: Svalbard

Water samples were analysed from 162 sites in Svalbard and Bear Island. A precipitation map for Svalbard was prepared. Critical loads are described as the highest loads of pollutants that will not lead to long-term, harmful effects on biological systems. Critical loads and exceedance of critical loads for input of strong acids to surface waters at Svalbard were calculated according to equations modified to fit the deposition conditions of the islands. Maps of critical loads and exceedance of critical loads were made for inputs of strong acids. Twelve percent of the ice-free area of mainly northern Svalbard has very low critical loads of acidity (< 25 kequiv./km2/year), whereas 67% of Svalbard is well protected against acidic precipitation (critical load of acidity > 100 kequiv./km2/year). A minor exceedance of critical load was recorded in 5% of the ice-free area of Svalbard, and only in the northern parts.