Staff Newsletter 24 November 2023

DEG Seminar - In person (hybrid)

Date / Time: Tuesday 28 November, 12:00-13:00

Location: ENV005 Lecture Theatre (and on Zoom if needed)

We encourage attendees to join us in person where possible to give our speaker a warm welcome, but if you can't make it to the building, you can click here to join on Zoom

Speaker name: Tom Chudley

Chair: David Rippin

Title: Crevasse-based controls on the hydrology and dynamics of the Greenland Ice Sheet

Blurb

The Greenland Ice Sheet (GrIS) is the largest contributor to global sea-level rise (SLR) from the cryosphere, with losses split approximately equally between surface melt and ice discharge into the ocean. A key uncertainty in quantifying 21st-century SLR is the extent to which meltwater modulates ice losses as it is transported to the base of the ice and, ultimately, the ocean. Half of Greenland’s seasonal melt is transferred to the bed of the sheet through crevasse fields, with implications for ice rheology, subglacial hydrology, iceberg calving, and subsequent feedbacks in ice dynamics. Despite increasing observations of the diversity and complexity of crevasse hydrology, crevasse drainage mechanics are poorly understood – particularly in comparison to other water pathways (lake drainage, moulins, finer-scale fractures) – and the vast majority of ice sheet models neglect to include crevasses at all. In this talk, I will outline the recent work I have been doing to help address the knowledge gap surrounding crevasse hydrology. I will discuss field-based observations of crevasses and their hydrology, recent advances in obtaining ice-sheet-wide observations from remote sensing, and potential links between crevasse drainage behaviour and ice dynamics. My ultimate aim is to use these derived relationships to properly parameterise spatially heterogenous crevasse hydrological behaviour into coupled models of Greenland Ice Sheet hydrology-dynamics.

Speaker Bio

Tom is a Leverhulme Early Career Fellow in the Sea Level, Ice and Climate Research Cluster in the Department of Geography at Durham University. He obtained his PhD from the Scott Polar Research Institute at the University of Cambridge, where he was part of the ERC-funded RESPONDER project and developed UAV-based methods to detect ice sheet dynamics at high spatial and temporal resolutions. Following this, he undertook a postdoc at the Ohio State University, working with Prof Ian Howat on detecting ice-sheet-change from large-scale velocity and elevation datasets. His fellowship is combining Earth observation, fieldwork, and numerical modelling to understand how crevasses will control the future of sea level rise from the Greenland Ice Sheet.