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No. 33: Statistical aspects in relation to Baltic Sea Pollution Load Compilation. Task 1 under HELCOM PLC-6

Larsen, S.E. & Svendsen, L.M. 2013. Statistical aspects in relation to Baltic Sea Pollution Load Compilation. Task 1 under HELCOM PLC-6. Aarhus University, DCE – Danish Centre for Environment and Energy, 34 pp. Technical Report from DCE – Danish Centre for Environment and Energy No. 33. dce2.au.dk/pub/TR33.pdf

Summary

HELCOM periodic pollution load compilation (PLC) assessments reports status and development in total annual runoff and total annual waterborne and airborne nutrient inputs to the Baltic Sea. This report deals with statistical methods for evaluating time series of annual runoff and nutrient inputs. Methods included are hydrological normalization of nutrient time series, trend analysis and a method for testing fulfilment of HELCOM Baltic Sea Action Plan (BSAP) nutrient reduction targets. Further is described how to fill in data gaps and to estimate the total uncertainty in nutrient inputs. These statistical methods are also included in the revised PLC guidelines.