The last British Ice Sheet: A review of the evidence utilised in the compilation of the Glacial Map of Britain

Abstract

This paper reviews the evidence presently available (as at December 2003) in an effort to stimulate further research on the last British Ice Sheet and promote a reconstruction of ice sheet behaviour based on glacial geology and geomorphology. The wide range of evidence that has been scrutinized for inclusion on the glacial map is assessed with respect to the variability of its quality and quantity and the existing controversies in ice sheet reconstructions. Landforms interpreted as being of unequivocal ice-marginal origin (moraines, ice-contact glacifluvial landforms and lateral meltwater channels) and till sheet margins are used in conjunction with available chronological control to locate former glacier and ice-sheet margins throughout the last glacial cycle. Subglacial landforms (drumlins, flutings and eskers) have been used to demarcate former flow patterns within the ice sheet. The compilation of evidence in a regional map is crucial to any future reconstructions of palaeo-ice sheet dynamics and will provide a clearer understanding of ice sheet configuration, ice divide migration and ice thickness and coverage for the British Ice Sheet as it evolved through the last glacial cycle.2

Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-temporal record of flow and substrate control

“…11 and 12. several differences: (1) the widespread abundance of meltwater channels on the ASE inner shelf suggests an important role for subglacial meltwater at times, when the ice sheet was more extensive, but the origin, flow rates, frequency, and duration of these flows is largely unknown at present ). In contrast, where meltwater landforms have been observed in northern hemisphere palaeo-ice sheets, the routing and function of meltwater is generally better understood (Fisher and Taylor, 2002;Evans et al, 2005b;Hä ttestrand and Clark, 2006). (2) Cross-cutting bedform sets, highlighting large switches in flow configuration in deglaciating ice sheets, are not apparent in the western ASE as they are in ice stream tracks across North America, the Canadian Shield, and offshore Norway (Stokes and Clark, 2001;Stokes et al, 2009).…”

The palaeoglaciology of the central sector of the British and Irish Ice Sheet: reconciling glacial geomorphology and preliminary ice sheet modelling

“…in correlating palaeo-ice sheet marginal oscillations in NE Ireland with North Atlantic and even global climate-ocean events, the behaviour of the BIIS throughout the last glacial cycle is poorly understood, due to patchy and largely nonsystematic mapping of glacial landforms (see C.D. Evans et al, 2005 for a review) and a weakly constrained chronological control on glacial deposits/events.…”

“…The model parameters within the mass balance model, the rate factor and the sliding coefficient have then been tuned to match three main constraints: First, to match the extent of the Younger Dryas ice coverage; second, ice free conditions before the Younger Dryas event; and third an approximate agreement with the current knowledge of ice sheet extent (cf. Bowen et al 2002;Evans et al 2005;Ó Cofaigh & Evans 2007). This provided good constraints for most of the parameters within the model.…”

Middle to Late Devensian glaciation of north‐east Scotland: implications for the north‐eastern quadrant of the last British–Irish ice sheet

“…The Pleistocene stratigraphical record in the north-east of Scotland ( Figure 1) includes glacigenic deposits and periglacial phenomena representing cold stages back at least to Marine Isotope Stage (MIS) 8, together with terrestrial sediments with a biological or pedological record of interstadial and interglacial climates , Evans et al, 2005. This unique record derived from over 175 years of published research in the region is important in understanding the history of the northern sector of the last BIIS and its interaction with ice flowing into the central NSB from Scandinavia.…”