Oliver Marsh

Research Area

I study ice shelf dynamics and mass loss mechanisms, primarily over short timescales (hours to decades).  Ice shelves are enormous, vulnerable floating ice masses that surround Antarctica restricting the rate of ice flow and global sea level rise.  They are lost through melting and fracture processes.

My research includes understanding melt variability and fracture evolution, collecting high resolution observations of ice movement from GNSS and satellite methods, and interpreting time variability in fracture growth in the context of wider strain fields through numerical modelling.  We work on understanding basic physical processes using high-resolution observations of glacier ice over short timeframes.  This includes ice response to environmental forcing (e.g. ocean tides, extreme events).  

Capturing short-term processes is vital for determining thresholds for instability and tipping points in ice sheet models and of critical importance is the effect of damage and cracks on the bulk properties of the ice, which is poorly understood and badly parameterised in models.

Project Interests

I am interested in supervising projects on strength and evolution of granular or fractured material and deformation / flow of such materials.  This could include variability due to intergranular matrix properties, fracture of grains and thermodynamic healing processes applied to understanding ice melange, ice rubble and fractured or damaged regions of ice shelves such as shear margins and calving fronts.  We have substantial observational data of glacier shear margins, grounding zones, tidewater calving and tabular calving rates.  Students may have opportunity to participate in fieldwork for validation, although this is certainly not a requirement.