IAP-25-067
Understanding grounding line dynamics in response to ice stream uncoupling
Understanding past, present and future ice-sheet response to climate change remains a critical challenge for society (IPCC 2023). A key avenue of global research efforts is the use of past glacial landscapes to inform our understanding of the nature and rate by which ice sheets can collapse when subjected to a range atmospheric and oceanic forcing parameters. In the UK, our world leading understanding of ice-sheet dynamics during the Last Glacial Maximum (LGM) has placed the last British-Irish Ice Sheet (BIIS) at the centre of international research efforts to understand ice/ocean/atmosphere interaction.
This PhD project will focus on the glacial history of the North Sea. The last decade has seen renewed interest in this sector of the BIIS with academic, commercial and industrial interests driving the need for a greater understanding of ice sheet dynamics and the geological and geomorphological evolution of the region. This work has been particularly critical for the development of UK offshore wind farms and government commitments to NetZero (Government to unleash the North Sea’s clean energy future – GOV.UK). The previously glaciated North Sea seabed currently provides the setting for some of the world’s largest offshore wind farms.
Several recent projects have demonstrated how the last British-Irish Ice Sheet (BIIS) and Fennoscandian Ice Sheet (FIS) interacted in the North Sea, leaving a complex imprint in relation to ice streaming, ice sheet collapse and unzipping, marine inundation and changing grounding line dynamics (Phillips et al., 2017; Hjelstuen et al., 2018; Roberts et al., 2019; Evans et al. 2021; Kirkham et al., 2025). Such a research focus has led to a much better understanding of ice sheet response to both internal (dynamic) and external (climatic) driving mechanisms (Clark et al., 2022), but many unanswered questions remain with respect to controls on ice sheet collapse during deglaciation.
This project aims to reconstruct grounding line evolution of key sectors of the BIIS following decoupling from the FIS in the North Sea. It will explore the following questions :
1. Was the pace/style of retreat driven by internal ice-sheet dynamics or external forcings?
2. Did ice stream decoupling trigger grounding instability?
3. How did ice shelves influence grounding line stability?
In summary, this studentship represents an opportunity to: i) develop an understanding of ice sheet dynamics, glacial systems and to explore the feedbacks that drive ice sheet response to climate forcing; ii) to develop key skills pertaining to the analysis and interpretation of geophysical, bathymetric and geological data; iii) to develop collaborations with both academic and industrial partners working at the cutting edge of glacial science and the UK’s renewable energy strategy.
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Image Captions
ice break-up; D H Roberts
Methodology
Data for the project will comprise 2D and 3D geophysical data acquired from offshore industrial partners and freely available data held in the Marine Data Exchange. It will also include data collected by the Britice-Chrono project in 2016.
Marine geophysical data will also comprise multibeam swath bathymetric imagery of seafloor morphology which will allow former ice sheet extent, flow direction and flow dynamics to be reconstructed.
Existing sediment cores held in Durham will be analysed for grain size, sedimentary structures, shear strength, and micro- and macrofaunal content. Selected samples will be dated using radiocarbon to obtain a chronology to determine the timing and rate of post-LGM ice stream and ice sheet retreat across the North Sea.
Project Timeline
Year 1
Identification of key sectors of the North Sea which capture BIIS dynamic behaviour in response to uncoupling; grounding line dynamics; grounding zone wedge and ice shelf formation. Collation of previously collected marine geophysical and sedimentological data. Initial analysis
Year 2
Data analysis of marine sediment cores and submission of samples for radiocarbon dating. Ongoing analysis of geophysical data.
Year 3
Completion of all data analysis and interpretation. Thesis writing. Presentation of results at conferences.
Year 3.5
Completion and submission of thesis. Finalise publication manuscripts; attend major international conference.
Training
& Skills
The student will receive training in the description analysis and interpretation of multibeam swath bathymetric datasets, sub-bottom profiler records and marine sediment cores. Broader, transferrable skills training will be provided via Durham University’s award-winning Career and Research Development (CAROD) group with courses in writing for publication, thesis writing, presentation skills etc. The student will also benefit from cross-disciplinary training provided through IAPETUS and partnerships with the renewable energy sector and overseas partners. The student will be a member of the Sea Level, Ice and Climate Research Cluster in Geography.
References & further reading
Clark, C.D., Ely, J.C., Hindmarsh, R.C., Bradley, S., Ignéczi, A., Fabel, D., Ó Cofaigh, C., Chiverrell, R.C., Scourse, J., Benetti, S. and Bradwell, T., 2022. Growth and retreat of the last British–Irish Ice Sheet, 31 000 to 15 000 years ago: the BRITICE‐CHRONO reconstruction. Boreas, 51(4), pp.699-758.
Evans, D.J., Roberts, D.H., Bateman, M.D., Clark, C.D., Medialdea, A., Callard, L., Grimoldi, E., Chiverrell, R.C., Ely, J., Dove, D. and Ó Cofaigh, C., 2021. Retreat dynamics of the eastern sector of the British–Irish Ice Sheet during the last glaciation. Journal of Quaternary Science, 36(5), pp.723-751.
Hjelstuen, B.O., Sejrup, H.P., Valvik, E. and Becker, L.W., 2018. Evidence of an ice-dammed lake outburst in the North Sea during the last deglaciation. Marine Geology, 402, pp.118-130.
Kirkham, J.D., Hogan, K.A., Larter, R.D., Arnold, N.S., Self, E., Games, K., Ely, J.C., Clark, C.D., Scourse, J.D., Shackleton, C. and Arndt, J.E., 2025. Change in iceberg calving behavior preceded North Sea ice shelf disintegration during the last deglaciation. Nature Communications, 16(1), p.3184.
Phillips, E., Cotterill, C., Johnson, K., Crombie, K., James, L., Carr, S. and Ruiter, A., 2018. Large-scale glacitectonic deformation in response to active ice sheet retreat across Dogger Bank (southern central North Sea) during the Last Glacial Maximum. Quaternary Science Reviews, 179, pp.24-47.
Roberts, D.H., Evans, D.J., Callard, S.L., Clark, C.D., Bateman, M.D., Medialdea, A., Dove, D., Cotterill, C.J., Saher, M., Cofaigh, C.Ó. and Chiverrell, R.C., 2018. Ice marginal dynamics of the last British-Irish Ice Sheet in the southern North Sea: Ice limits, timing and the influence of the Dogger Bank. Quaternary Science Reviews, 198, pp.181-207.
