Contributors: SMHI Hydrology Research (FoUh), Rossby Centre (SMHI), Lund University, Luleå University of Technology
In this WP, the output from RCMs and Earth System Models generated in WP1 and in the database of the EU project ENSEMBLES will be evaluated and interpreted with respect to hydrologically relevant variables and relationships. Further downscaling and bias compensation will be addressed when relevant.
- Successively higher-resolution RCM output will be compared against relevant observations (e.g. station data, gridded data and radar fields). The comparison will cover different temporal and spatial scales with the main focus lying on precipitation extremes.
- The scaling method will be improved by considering the large-scale circulation pattern (CP). The classification will be optimised to generate robust and accurate scaling parameters. It will be investigated to which degree the RCM output reproduces observed circulation patterns.
- The analysis of EC-Earth/CMIP5 will focus on relationships between large-scale atmospheric predictors (geopotential height, wind speeds, humidity etc.) and spring flood volumes in large catchments.
- The stochastic downscaling scheme of Olsson et al. (2008), based on the weather situation as estimated from additional RCM variables (e.g. cloud cover and precipitation type) will be extended to consider not only point precipitation but also the frequency distribution of precipitation intensities inside the box.
Tasks and deliverables:
2.1 Evaluation of Regional Climate Model precipitation (RC/FoUh/LUT)
2.2 Interpretation (climate model grid scale):
a) Circulation Pattern-based scaling (FoUh)
b) Evaluation of EC-Earth/CMIP5 results (RC/FoUh/LUT)
2.2 Downscaling (sub-modelgrid scale)
a) Process-based precipitation downscaling to point value (FoUh)
b) Process-based precipitation downscaling to intra-gridbox distribution (FoUh)