HiLandEr - Hidden water and landscape erosion

NEWS

WE ARE BUILDING THE TEAM (Jan 2024). Currently, we are in the process of recruiting the two PhD students from the pool of submitted applications. For efficient project enrollment, we will be out in the field for scouting, expecting crisp weather and a shiny landscape.

WE ARE HIRING (Nov 2023). We are seeking early stage researchers to take on one of two PhD positions in the HiLandEr project. The position at IFPEN, France, will focus on numerical model development (details and call see here). The position at Uni Göttingen, Germany, will focus on instrumental field data collection and analyses (call, application form).

SCOPE

Catastrophic floods and sustained droughts will be increasing as our climate changes. It is uncertain how this change will impact the watersheds of major rivers during hydrological extremes. A crucial element in the routing of discharge, and its erosive impact on landscapes, is subsurface storage of water and its pathways within the critical zone. The challenge is in both observing and predicting change in subsurface water amounts and fluxes.

In HiLandEr, we explore this important hidden water compartment from two complementary sides: by spatially distributed measuring (overcoming limitations of current point-like measurements) and by landscape wide modelling (overcoming current model oversimplifications). We will jointly survey groundwater and fluvial dynamics using passive seismology and water chemistry to build a picture of the subsurface flow paths and quantities. We will in parallel develop the methods to efficiently numerically model both the hydrology and sediment yield of the system. This research project will help improve flood anticipation, give insight into hydraulic breakpoints (initiation of overland flow and erosion), and understand future response in the critical zone due to climate change.

TEAM

HiLandEr is a joint ANR-DFG funded research project that brings together four research institutes in France (IFP Energies Nouvelles Paris & Université de Rennes) and Germany (Georg-August University Göttingen & GFZ Potsdam). With HiLandEr, there will be two PhD projects, enrolled at IFPEN and Uni Göttingen. The IFPEN project (Call for PhD position, open) focusses on the development of a numeric landscape evolution model that can describe the interaction between the surface and the subsurface and is capable of predicting the risk of future catastrophic floods on a 10-to-100-year timescale (scope see here). The Göttingen project (Call for PhD position, open) will pursue an empirical approach, by installing a network of seismic and hydrological stations to constrain both surface fluxes and groundwater dynamics (background see here). The project bridges scientific fields, including hydrology, hydrogeology, geomorphology, geochemistry, and sedimentology in order to understand how the subsurface impacts erosion and sediment yield.

APPROACH

Both projects will be set up in nested upland catchments of the Eifel region, Germany. That area, characteristic for many European landscapes, had experienced a catastrophic flood event in summer 2021 (details see here). Through rapid response actions, there are very high-resolution ground data available. In addition, a GFZ-coordinated large-N-array experiment contributes six months of data from 350 seismometers, spread across the Eifel. That pool of information (Fig. below, left), in combination with additional instruments set up during the project phase (Fig. below, right) and the transfer of those data into a numerical model approach, allows to i) observe water and sediment discharge and its modulation by critical zone dynamics, ii) characterisating the relationship between subsurface saturation and erosion events, and iii) constraining water pathways and causes of non-linear system behaviour.