This work package consists of four Tasks, which develop a set of nested tools and investigations.
The tasks are:
- Task 3.1: RCM Simulations, focussing on regional scales and linked to GCMs;
- Task 3.2: Distributed catchment response to scenarios, focussing on basin scales and linked to RCMs by means of appropriate downscaling techniques;
- Task 3.3: Subgrid variability of the response, focussing on the local/point scales and providing a very detailed modelling of processes that are characterized by significant small scale dynamics and nonetheless have a considerable impact, either on processes at a larger scale, or directly on the socio-economic compartment (the latter is, for instance, the case of the stability of glaciers that may endanger mountain villages)
- Task 3.4: Extreme and hazards, focussing specifically on the treatment of extreme values of both historical data and simulations, thus recognizing changes in the frequency of floods and droughts a major threaten to society with a potentially high impact.
The links among T 3.1, 3.2, and 3.3 require the development and implementation of methodologies that overcome the limitations of existing studies. In particular, dynamic downscaling techniques will be combined with statistical/stochastic methods to obtain the maximum benefit of both methodologies. Simulations run at the local scales will allow preserving the often important small scale variability into larger scale models by developing appropriate techniques to scale-up from the point to the basin scale. The overall nested character of the modelling concept of WP2 will thus allow the generation of catchment scale scenarios by means of distributed hydrological models, which are fed by downscaled space-time scenarios, and at the same time resolve the small scale variability of processes using detailed models that either are nested within the raster of the hydrological model itself or supply an external input. The hydrological model and small scale detailed models will be used to generate the scenarios, which form the basis for the analyses of WP43. Figures 1 and 2.2 summarize the link among the different subtasks and the flow of information with the other WPs.