An ensemble analysis of climate change impacts on streamflow seasonality across 11 large river basins
The paper investigates climate change impacts on streamflow seasonality for a set of eleven representative large river basins covering all continents and a wide range of climatic and physiographic settings. Based on an ensemble of nine regional hydrological models driven by climate projections derived from five global circulation models under four representative concentration pathways, we analyzed the median and range of projected changes in seasonal streamflow by the end of the twenty-first century and examined the uncertainty arising from the different members of the modelling chain. Climate change impacts on the timing of seasonal streamflow were found to be small except for two basins. In many basins, we found an acceleration of the existing seasonality pattern, i.e. high-flows are projected to increase and/or low-flows are projected to decrease. In some basins the hydrologic projections indicate opposite directions of change which cancel out in the ensemble median, i.e., no robust conclusions could be drawn. In the majority of the basins, differences in projected streamflow seasonality between the low emission pathway and the high emission pathway are small with the exception of four basins. For these basins our results allow conclusions on the potential benefits (or adverse effects) of avoided GHG emissions for the seasonal streamflow regime.
- Addor N, Rössler O, Köplin N et al (2014) Robust changes and sources of uncertainty in the projected hydrological regimes of Swiss catchments. Water Resour Res 50:7541–7562. doi:10.1002/2014WR015549
- Beldring S, Engen-Skaugen T, Førland EJ, Roald LA (2008) Climate change impacts on hydrological processes in Norway based on two methods for transferring regional climate model results to meteorological station sites. Tellus, Ser A Dyn Meteorol Oceanogr 60 A:439–450. doi:10.1111/j.1600–0870.2008.00306.xGoogle Scholar
- Huang S, Kumar R, Flörke M et al (2016) Evaluation of an ensemble of regional hydrological models in 12 large-scale river basins worldwide. Climatic Change. doi:10.1007/s10584-016-1841-8
- Samaniego L, Kumar R, Breuer L et al (2016) Propagation of forcing and model uncertainties on to hydrological drought characteristics in a multi-model century-long experiment in large river basins. Climatic Change. doi:10.1007/s10584-016-1778-y
- Vetter T, Reinhardt J, Flörke M et al (2016) Evaluation of sources of uncertainty in projected hydrological changes under climate change in 12 large-scale river basins. Climatic Change. doi:10.1007/s10584-016-1794-y
- Walsh RP, Lawler DM (1981) Rainfall seasonality: description, spatial patterns and change through time. Weather 36:201–208. doi:10.1002/j.1477-8696.1981.tb05400.x