Water Quality and Sediment Behaviour of the Future: Predictions for the
21st Century (Proceedings of Symposium HS2005 at IUGG2007, Perugia, July
2007). IAHS Publ. 314, 2007, 90-97
Modelling
climate change impact on phosphorus load in Swedish rivers
JÖRGEN ROSBERG & BERIT ARHEIMER
Swedish Meteorological and Hydrological Institute (SMHI), SE-60176 Norrköping, Sweden
berit.arheimer@smhi.se
Abstract Climate change impact on phosphorus load is modelled and compared for two Swedish rivers with different characteristics. The modelling was based on the ECHAM4/OPYC3 B2 scenario, downscaled with the RCA3 model and a complementary scaling procedure. Hydrology and phosphorus concentrations were simulated for the time period 1961–2100, using the ICECREAM model for arable leaching, and HBV-NP model for integrated catchment analysis including all sources, erosion and major turnover processes at the catchment scale. The results show 10% increased load, and 25% reduced load, respectively, for the rivers. In both catchments, phosphorus leaching from crops was found to increase; however, this load was only a minor fraction in one river. For the other river, a suggested plan of measures for reducing load was found to be less effective in a future climate. Finally, the study concludes that climate change impact studies are based on a chain of assumptions and uncertainties which should be emphasised in future research.
Key words
catchments; climate change impact study; phosphorus; river load; Sweden