Timing, pace and controls on ice sheet retreat: an introduction to the BRITICE‐CHRONO transect reconstructions of the British–Irish Ice Sheet

Chris D Clark,Richard C A Hindmarsh,James D Scourse,Derek Fabel,Colm Ó Cofaigh,Richard C Chiverrell

doi:10.1002/jqs.3326

Abstract

ABSTRACTMotivated to help improve the robustness of predictions of sea level rise, the BRITICE‐CHRONO project advanced knowledge of the former British–Irish Ice Sheet, from 31 to 15 ka, so that it can be used as a data‐rich environment to improve ice sheet modelling. The project comprised over 40 palaeoglaciologists, covering expertise in terrestrial and marine geology and geomorphology, geochronometric dating and the modelling of ice sheets and oceans. A systematic and directed campaign, organised across eight transects from the continental shelf edge to a short distance (10s of kilometres) onshore, was used to collect 914 samples which yielded 639 new ages, tripling the number of dated sites constraining the timing and rates of change of the collapsing ice sheet. This special issue synthesises these findings of ice advancing to the maximum extent and its subsequent retreat for each of the eight transects to produce definitive palaeogeographic reconstructions of ice margin positions across the marine to terrestrial transition. These results are used to understand the controls that drove or modulated ice sheet retreat. A further paper reports on how ice sheet modelling experiments and empirical data can be used in combination, and another probes the glaciological meaning of ice‐rafted debris.

Highlights

On a warming Earth, ice sheets reduce in mass and raise the global sea level
To help improve the robustness of forecasts, and motivated by the quote below, the BRITICE‐CHRONO project sought to develop knowledge of the former British–Irish Ice Sheet so that it can be used as a data‐rich environment to improve ice sheet modelling approaches
A further paper reports on how ice sheet modelling experiments and empirical data can be used in combination (Ely et al, 2021), and another probes the glaciological meaning of ice‐rafted debris (Wilton et al, 2021)

Summary

Introduction

On a warming Earth, ice sheets reduce in mass and raise the global sea level. Glaciologists have been galvanised into action by societal requirements to forecast this sea level rise over the coming decades and centuries. This special issue mostly synthesises the results from the above dating campaign, reported in a series of transect papers that document the timing of ice marginal positions at the maximum extent, and as the ice margin withdrew.

Results

Conclusion