How warm was Britain during the Last Interglacial? A critical review of Ipswichian (MIS 5e) palaeotemperature reconstructions

Abstract

The Last Interglacial [LIG, equivalent to marine isotope stage (MIS) 5e] was a period of enhanced global warmth, with potential significance for understanding future climate warming. It has long been proposed that the LIG in Britain (the Ipswichian Interglacial) was significantly warmer than present, based on the occurrence of fossils of extant thermophilous plant and animal species intolerant of the current climate. Here, we review the evidence for palaeotemperatures that can be derived from such fossil taxa (beetles, ostracods, plant macrofossils and herpetiles) to assess the level of warmth that Britain experienced during the LIG. Quantified palaeotemperature reconstructions generated for eight British sequences indicate that the LIG was likely to have been warmer than the present but at only one site (Trafalgar Square) is there strong evidence for climates that were significantly warmer than those experienced during the Holocene. Consequently, while there is evidence to support the idea that the thermal regime of the LIG in Britain was different from that of the Holocene, this evidence is restricted to a single site. The paper concludes by discussing the thermal regime of the LIG in Britain in the context of its role as an analogue for future warming in the 21st century and beyond.

Fossils from Quaternary fluvial archives: Sources of biostratigraphical, biogeographical and palaeoclimatic evidence

“…Evidence corroborating and strengthening established biostratigraphical frameworks (Schreve, 2001a, b) has been obtained, together with substantial new understanding of the palaeoclimatic and palaeoecological significance of numerous plant and animal species that occur commonly within fossil assemblages (e.g. Candy et al, 2012Candy et al, , 2015Candy et al, , 2016. Certain taxa appear to have been extremely widespread at particular times during the Pleistocene, only for their ranges to fragment in response to subsequent environmental pressures.…”

“…An important aspect of recent research has been the recognition of greater climatic complexity recorded in terrestrial interglacial sequences, leading to a renewed appreciation of the potential ability of multi-proxy palaeontological analyses to discern marine oxygen isotope substages (e.g. Schreve, 2001b;Ashton et al, 2008;Koutsodendris et al, 2010Koutsodendris et al, , 2011White et al, 2013;Candy et al, 2014Candy et al, , 2016. In Britain and northern Europe, this has been especially relevant to sequences attributed to the MIS 11 Hoxnian/Holsteinian Interglacial (e.g.…”

“…Gliozzi et al, 1997;Schreve, 2001a;Schreve and Bridgland, 2002;Bridgland et al, 2004;Markova, 2007;Megirian et al, 2010) and for detailed palaeoclimatic and palaeoenvironmental analyses (e.g. Coope, 2010;Schreve and Candy, 2010;Candy et al, 2010Candy et al, , 2015Candy et al, , 2016Kahlke et al, 2011;Limondin-Lozouet et al, 2010;Rule et al, 2012;White et al, 2013). The contribution of the Fluvial Archives Group (FLAG) to these research areas over the last 20 years has been considerable: two UNESCO-sponsored International Geological Correlation Programme (IGCP) projects, entitled 'Global correlation of Late Cenozoic fluvial deposits' (IGCP 449) and 'Fluvial sequences as evidence for landscape and climatic evolution in the Late Cenozoic' (IGCP 518), ran under the auspices of FLAG between 2000 and 2007 Westaway et al, 2009).…”

“…The resulting palaeontological data have the potential to be interpreted on a variety of scales, ranging from considerations of changing climatic conditions during a single interglacial in a given region (e.g. Candy et al, 2016) to comparisons between different interglacials (e.g. Limondin-Lozouet and Preece, 2014) and even identification of patterns at the marine oxygen isotope substage level (Schreve, 2001b;Candy and Schreve, 2007;Ashton et al, 2008;White et al, 2013).…”

Evidence for the early onset of the Ipswichian thermal optimum: palaeoecology of Last Interglacial deposits at Whittlesey, eastern England

“…The vast majority of the Ipswichian sites recognized by Lewis et al (2010) fall into the early temperate pollen biozone IIb (Table 1). Candy et al (2016) used the data from five of these Ip IIb sites (Bobbitshole, Deeping St James (Keen et al, 1999), Swanton Morley (Phillips, 1976;Coxon et al, 1980), Tattershall Castle (Holyoak & Preece, 1985) and Trafalgar Square (Preece, 1999), together with data from Woolpack Farm (Gao et al, 2000), to assess how warm Britain was during the Ipswichian Interglacial, showing that only the sequence from Trafalgar Square convincingly demonstrates temperatures warmer than during the Holocene thermal optimum, though all are warmer than the present day.…”