Timescale: Oct. 2021 – Sept. 2024
Prof. Eva Eibl, University of Potsdam
Dr. Sigrid Rössner, GFZ Potsdam
Meltwater, rainwater and geothermal fluids accumulate in subglacial or glacier-dammed lakes and drain in hazardous floods, e.g., in Iceland, the Alps, Greenland and the Andes. These floods are recognized as the most common largely distributed hazard to life, property and economy, costing billions of dollars every year. Early warning of these floods is locally achieved using hydrological instruments in the affected glacial rivers that can however only detect a flood that has already progressed from beneath the ice into the river. Early-warning can be improved by using GPS instruments that are deployed on the ice surface on top of some of the lakes, but their maintenance over the years is challenging (Eibl et al., in review).
The project I11 focuses on seismic signals generated during the propagation of subglacial floods that can be recorded from a safe distance outside the glacier. We will process and interpret recordings from seismic arrays and rotational sensors jointly with the observations made by hydrological and GPS data. Pre-existing data from Greenland and Iceland can be used as a starting point. Further datasets will be collected in the European Alps and maybe in the Himalayas in order to address the following objectives:
We expect to be able to track most subglacial floods with seismic instruments even if they propagate beneath the glacier. We will characterise the spatial and temporal evolution of these floods using seismic data in combination with datasets from other disciplines. This will help us to understand the mechanisms that trigger/ drive a flood and will improve the prediction methods, modelling and forecasting techniques.
Dedicated Regional Cluster: Central Europe / European Alps and Himalayas
Related PhD-projects: I4 (first cohort, Georg Veh) and Q8 (second cohort, Melanie Fischer): the project is linked to I4 and Q8 that were devoted to the detection, frequency, and magnitude of glacial outburst floods (GLOFs) in the Himalayas.
Responsibilities: The PhD-project “Discrimination of Subglacial Flood Types based on Seismological and Remote Sensing Data” aims at defining and differentiating the fingerprints of subglacial floods using a combination of seismological as well as remote sensing tools and observations. The project will start with a dataset of the flood in September-October 2015 in Iceland to quantify the links between the different methods and assess the fingerprint of this event. We will then compare this to other subglacially propagating floods mainly in Iceland from the Skaftá cauldrons and Grímsvötn caldera lake, and in Switzerland at Gornersee and Plaine Morte glaciers. We will assess the link between flood trigger, flood mechanism, tremor amplitude, flood discharge and the possible pressure wave at the beginning of a flood. Methods for this project will involve analyses of seismological data, remote sensing data as well as modelling of lake outburst and flood propagation.
Requirements: We are seeking applications from highly motivated individuals with a strong background in seismology and physics with an interest in remote sensing and interdisciplinary data analysis. Fluency in the English language (speaking and writing) as well as the willingness to work in an interdisciplinary team are essential. Experience with seismological software packages, processing of seismological datasets and remote sensing data or modelling is desirable. We expect a solid background in mathematics, physics, programming skills (e. g. Python) and interest in natural hazards such as subglacial floods. A basic knowledge of glaciology or seismic tremor will be of advantage for this post.