Methods for processing and adaptation of data from global and regional climate models have opened new doors within hydrological research. Improved connections between climate models and hydrological models have resulted in researchers being able to examine the climate effects on water flows, floods and transport of nutrients. They have also created new hydrological future scenarios for Sweden and Europe, as well as knowledge of local climate impact on water flows and water quality.
Intense rainfall
Researchers at SMHI have developed new methods for estimating future intense precipitation, which is valuable for climate adaptation and social planning.
"We have developed tools which can describe the heavy torrential rains and simulate how water flows quickly change in smaller drainage basins. This is important knowledge when, for example, a city will prepare for future climate changes," says Jonas Olsson, researcher within hydrology at SMHI and coordinator of the strategic research project Hydroimpacts 2.0.
Impact on water quality
The effects of urbanisation and changed sources of contamination can play a larger role for the quality of surface water than the climate change itself. More contaminants will also be transported when amounts of rainfall will increase in the future.
"The smart growth of cities is therefore a key factor for adapting and maintaining a good quality of surface water in the future," says Matthias Borris at Luleå University of Technology, who has conducted studies on the quality of surface water in Skellefteå.
Transport of contaminants
The spread of water contaminants has also been studied. Magnus Persson at Lund University concludes that where the rainfall amounts will increase in the future, you can expect a slightly larger risk of spread of contaminants down to the ground water. To a certain extent the increasing amounts of rainfall will be counteracted by increasing evaporation.
In northern Sweden, where the difference between rainfall and evaporation is largest, you can therefore expect a slightly larger increase in contamination risks. Even though the transport speeds are not expected to increase by more than a few per cent, there may be reasons to watch over the safety areas for ground and surface water sources, particularly in northern Sweden.
Eutrophication in the Baltic Sea
The countries surrounding the Baltic Sea have agreed on reduced emissions of nitrogen and phosphorus. An analysis shows that it is possible to attain the targets of lower transport of nutrients to the Baltic Sea at the next turn of the century. The climate change both helps and worsens the opportunities.
In the strategic research project Hydroimpacts 2.0, experts within hydrology, climate modelling and IT from SMHI, Luleå University of Technology and Lund University have collaborated. The project is funded by the Swedish Research Council Formas and will be concluded in 2014.