Mathematical Modelling of a Subglacial 'Blister' in the Event of a Supraglacial Lake Drainage Event

The Greenland Ice Sheet is melting at higher altitudes due to climate change. This meltwater pools into surface lakes where it can stay for decades. Such 'supraglacial' lakes have been observed to drain completely within a few of hours. Due to a sudden influx of fluid at the glacier base, the entire ice sheet in the vicinity of the draining lake is hydraulically jacked from the bedrock leading to ice sheet surface uplifts on the order of metres. Such features are commonly referred to as 'subglacial blisters' and form one of many components that affect the evolution of the subglacial drainage system.
Current numerical models of Greenland's subglacial drainage system are unable to resolve such short and massive events. The aim of this project is to more closely model the evolution of a subglacial blister with the view to fitting a simplified version into a wider subglacial drainage system model. The model will be built upon the mathematical theory of hydrofracture, in which a crack grows between two surfaces due to the pressure of fluid contained within it.
First the project will focus on the growth of a single blister in a flat environment - understanding the influences of turbulent and laminar flow, and how quickly any water will 'leak-off' into the surrounding drainage system. Then the project will extend to a sloped domain in which meltwater is driven towards the ice sheet boundary. The purpose of this extension is to understand where and over what time scale a subglacial blister can affect the drainage system.
This project falls within the EPSRC Continuum Mechanics research area, specifically in relation to fluid and solid mechanics. Hydrofracture modelling is most commonly used in the oil and gas industry and this project will instead re-utilise the theory for a natural geophysical process.