Project P8 by Amalie Skålevåg (University of Potsdam): Changing water and energy conditions and their relevance for water and sediment pulses in Alpine areas

Timescale: Oct. 2021 – Sept. 2024

Supervisors:

Prof. Axel Bronstert, University of Potsdam

Prof. Oliver Korup, University of Potsdam

Background

Climate change directly affects hydrologic and energy conditions and processes at the land surface. In high mountain areas such effects can be particularly pronounced and diverse, because of strong state and process variations in space (related to altitude, relief, exposition, etc.) and time (related to  seasonality, snow cover, etc.). Of particular interest is the changing temperature regime of substrates such as rock and soil, which may compromise the stability of hillslopes and river banks. Altered freeze-thaw regimes may change the mobilization of landslides, debris flows, or similar sediment pulses that are triggered by heavy rainfall and snowmelt. The associated change in the hazards of these events, remains unclear, although a common notion is that this hazard is likely to increase.

Objectives and Methods

The overall objective is to learn more about the dynamics of cascading meteo-/hydro-/geomorphological events triggered by heavy rainfall or snow melt.

The project will focus on

• Building of a database of extreme sediment-transport events (esp. debris flows) in recent years, including sites of origin, corresponding field and event conditions (triggering rainfall, synoptic conditions, snow/ice melt, soil temperatures etc.);
• Identifying and comparing different types of debris-flow events by pattern analysis of temperature, discharge, and suspended sediment time series;
• Exploring the feasibility of novel satellite products to derive information on soil moisture and temperature, in particular soil freeze-thaw, for selected alpine hillslopes;
• Exploring the feasibility of UAV technology to derive information on thermal surface / soil temperature dynamics / soil freezing, for selected alpine hillslopes and river bank slopes;
• Modelling of surface water and energy budgets for selected key surface areas to generalize field data and create the methodological basis for regional transfer and prediction for future climatic conditions;
• Empirical and probabilistic modelling of sediment-flow events, depending on site conditions and hydro-meteorological event characteristics.

The following results are expected:

• Quantification of altered water and energy surface conditions relevant for hydro/sediment hazards in alpine areas
• Systematic analysis of regional data on sediment dynamics in rivers, sudden sediment releases in alpine landscapes and landscape and hydro-meteorological events
• Extrapolation (prediction) of such conditions for future, warmer environmental conditions or for selected region in the Alps.

Dedicated Regional Cluster: European Alps

Related PhD-projects: I4 (first cohort, Georg Veh), P1 (first cohort, Ugur Öztürk), P2 (first cohort, Berry Boessenkool/Erwin Rottler) and P5 (second cohort, L. Katharina Schmidt)