Inception, growth and decay of the British-Irish Ice Sheet

The potential for collapse of the West Antarctic Ice Sheet (WAIS), the only modern marine-based ice sheet today, remains the largest source of uncertainty in projections of future sea-level rise. This uncertainty comes from an imperfect understanding of ice sheet processes and their internal variability in response to climate and ocean forcing. Improving such understanding for palaeo-ice sheets has important implications for modelling and forecasting of future changes in modern ice sheets. The British-Irish Ice Sheet (BIIS), that extended over the UK and Ireland during the Quaternary, was marine-terminating, drained by large ice streams, and was particularly sensitive to oceanographic and climatic changes due to its geographical position bordering the North Atlantic. This makes it an excellent analogue to gain further insight into the dynamics of modern marine-terminating ice sheets. However, surprisingly little is known about BIIS inception and older glaciations prior to the last glacial period. This project aims to fill this scientific gap by identifying specific drilling sites along the UK and Irish continental margin for the submission of a mission-specific IODP proposal on the reconstruction of the inception, and cycles of growth and decay of the BIIS during the Cenozoic. The target areas and research themes for the final IODP proposal have already been identified based on previous research, but the selection of specific drill sites for each area requires careful consideration and an assessment of the suitability and safety of each site. The extensive suite of geophysical and geological datasets already available on this margin will be analysed by the PDRA, under the guidance of the UK-based PI and co-Is, specifically for this purpose. The proposal includes a workshop in month 10 of the project to bring together a team of named collaborators from the UK, Ireland, Belgium, Norway and Australia, with research experience on the BIIS and glacial processes on this continental margin as well as experience with IODP processes and data, to develop the final IODP proposal and eventually deliver the first full reconstruction of the BIIS from its inception.