Subproject HYDRO: Discharge

The Chair of Hydrology and River Basin Management at the Technical University of Munich is working on the subproject “HYDRO”. Project leaders are Prof. Dr. Gabriele Chiogna and Prof. Dr. Markus Disse, project collaborator Florentin Hofmeister MSc is completing his PhD thesis within the project.

The “HYDRO” subproject investigates climate change impacts on the hydrosphere of Alpine catchments since the end of the Little Ice Age (1850). The overall focus is on the investigation of changing frequency and magnitude of observed and simulated extreme events, such as floods, droughts, extreme melting events resulting from heat waves, occurrence of rain-on-snow events and thunderstorms. In addition to the analysis of hydrological and meteorological time series, hydrological modeling with the physically based model WaSiM is carried out in all three catchments. On the one hand, this should ensure that the mechanisms of runoff generation in the different study areas are properly understood and on the other hand, the model simulations allow to close data gaps in the past and to look into the future.

Uncertainties in hydrologic modeling results are reduced by using high-resolution meteorological data, remote sensing data (e.g., glacier extent, snow cover), information on soil properties (e.g., soil structure, permafrost, and vegetation cover), and additional measurements such as discharge temperature and electrical conductivity. Hydrological data will be collected in intensive measurement campaigns and continuously throughout the project phase (2019-2021). This includes innovative measuring methods such as the AutoSalt system from the Canadian company Fathom Scientific for automated discharge measurements, which are being further developed in close cooperation.

The specific focus of the multi-criteria calibration and validation of the hydrological model will be on runoff generation due to snow, glacier and permafrost melt. The influences of climate, glacier and snow dynamics, geomorphological changes, and land use changes on the hydrological response from the Alpine catchments will be analyzed using calibrated models of different complexity (depending on data availability) within the periods 1850-1920, 1920-1980, and 1980-2021.