Oxygen isotopic evidence for high‐magnitude, abrupt climatic events during the Lateglacial Interstadial in north‐west Europe: analysis of a lacustrine sequence from the site of Tirinie, Scottish Highlands

Abstract

The Last Glacial to Interglacial Transition (LGIT) is a period of climatic instability. δ18O records are ideal for investigating the LGIT as this proxy responds rapidly to even minor climatic oscillations. Lacustrine carbonates offer the opportunity to investigate spatial diversity in patterns of climatic change during the LGIT but this requires the generation of δ18O records from a range of latitudinal and longitudinal settings. This study presents a coupled pollen and stable isotopic study of lacustrine carbonates spanning the Windermere Interstadial (the British equivalent of Greenland Interstadial 1, the Lateglacial Interstadial) from the site of Tirinie in the Scottish Highlands, a region where δ18O records are absent. The Interstadial is characterized by three δ18O peaks, warm intervals, and two δ18O declines, cold episodes, the timing of which is constrained by the presence of crypto‐tephra. The landscape at Tirinie was highly responsive to these climatic oscillations as the sedimentary and pollen record respond to each isotopic shift. The paper concludes by highlighting that, across the British Isles, lacustrine δ18O records of the Interstadial have a consistent stratigraphy/structure, although the magnitude of the isotopic shifts is regionally variable. Potential causes of this variability are discussed.

Establishing tephrostratigraphic frameworks to aid the study of abrupt climatic and glacial transitions: a case study of the Last Glacial-Interglacial Transition in the British Isles (c. 16-8 ka BP)

“…While parts of Scotland were deglaciated by c. 16.0 ka BP 1072 (Clark et al, 2012; Hughes et al, 2016; Ballantyne and Small, 2018), the current tephra record suggests that much of the Scottish Highlands did not become ice-free until, or 1074 marginally before, c. 14.0 ka BP. This inference is indicated by the frequency with which the 1075 Borrobol Tephra is found close to the base of the earliest sediments to have accumulated in 1076 a number of lake basins (Walker and Lowe, 2017; SupplementaryFigure S1), whereas in the 1077 Tirinie basin located in the Grampian Highlands, the younger Penifiler Tephra occupies this 1078 position(Candy et al, 2016). Thus far, the only terrestrial sites in the British Isles in which 1079 pre-WI tephra layers have been discovered are located on the Summer Isles in The Minch,…”

Identification of the Askja-S Tephra in a rare turlough record from Pant-y-Llyn, south Wales

“…Tephra deposits have huge potential as an alternative dating technique for such sequences (e.g. Candy et al, 2016;Timms et al, 2016) and we present the first positive findings in Wales to date a carbonate-rich record retrieved from a turlough.…”

Palaeotemperature estimation in the Holsteinian Interglacial (MIS 11) based on oxygen isotopes of aquatic gastropods from eastern Poland

“…The occurrence of characteristic plants combined with the characteristic regional floristic succession reveal air temperature changes through the Holsteinian Interglacial (Krupiński 1995;Nitychoruk 2000), whereas the mollusc assemblages (Albrycht et al 1995;Szymanek 2012Szymanek , 2013Szymanek , 2014a, oxygen and carbon isotopes (Szymanek 2016;Szymanek et al 2016) and shell elemental composition of V. diluvianus and V. piscinalis (Szymanek 2017) allow the definition of environmental conditions in the studied water bodies. Because this study deals with lakes which no longer exist there still remain some doubts in their catchment characteristics (cf., Candy et al 2016), and the discussion may appear somewhat subjective at some points, but it is still significant for the interglacial record, which in general is devoid of oxygen isotope temperature reconstructions. Correlation with other proxies makes these assumptions more reliable (cf., von Grafenstein et al 2013).…”

“…As mentioned earlier, their hydrology is characterised by molluscs, which, in general, point to rather shallow, overgrown littoral zones with possible changes in the water-level and the near-shore aquatic vegetation during the lakes' existence. These intra-basin changes are discounted in scenario 1, based on the narrow range of δ 18 O Shell values suggesting stable isotope conditions (cf., Candy et al 2016), but will further be considered in scenario 3. The river supply is not unequivocal in the studied lakes, but the admixture of rheophile species indicates possible water movements connected with the currents and/ or the wave action (Szymanek 2012(Szymanek , 2013(Szymanek , 2014a.…”

“…The more arid conditions of the Pinus-Larix Zone and the post-optimum (Krupiński 1995;Pidek 2003 were associated with the rearrangement of plant communities in the study area, reflected by the expansion of pine forest with larch and birch in the cost of oak, fir and hornbeam Nitychoruk 1995, 1996;Krupiński 1995Krupiński , 2000Bińka et al 1997;Nitychoruk et al 2005), and the episodes of low water stands indicated by abundant V. cristata, A. lacustris, G. crista and other species typical of macrophyte-covered bottom in shallow waters (Szymanek 2014a, b). To be sure, the lake systems might become more susceptible to evaporation under these conditions (Candy et al 2016;Szymanek 2016;Szymanek et al 2016), but the assumption of 2‰ difference in evaporative enrichment between the phases of oceanic and continental influences, reveals a highly unlikely, approximately 10°C rise in water temperatures of Ortel Królewski and Szymanowo Lakes in the Pinus-Larix Zone and the post-optimum, respectively (Text-figs 4, 5). The narrow range of oxygen isotope shell values in .…”