It is suggested that the GRIP Greenland ice‐core should constitute the stratotype for the Last Termination. Based on the oxygen isotope signal in that core, a new event stratigraphy spanning the time interval from ca. 22.0 to 11.5 k GRIP yr BP (ca. 19.0–10.0 k 14C yr BP) is proposed for the North Atlantic region. This covers the period from the Last Glacial Maximum, through Termination 1 of the deep‐ocean record, to the Pleistocene–Holocene boundary, and encompasses the Last Glacial Late‐glacial of the traditional northwest European stratigraphy. The isotopic record for this period is divided into two stadial episodes, Greenland Stadials 1 (GS‐1) and 2 (GS‐2), and two interstadial events, Greenland Interstadials 1 (GI‐1) and2 (GI‐2). In addition, GI‐1 and GS‐2 are further subdivided into shorter episodes. The event stratigraphy is equally applicable to ice‐core, marine and terrestrial records and is considered to be a more appropriate classificatory scheme than the terrestrially based radiocarbon‐dated chronostratigraphy that has been used hitherto. © 1998 John Wiley & Sons, Ltd.

The last interglacial, commonly understood as an interval with climate as warm or warmer than today, is represented by marine isotope stage (MIS) 5e, which is a proxy record of low global ice volume and high sea level. It is arbitrarily dated to begin at approximately 130,000 yr B.P. and end at 116,000 yr B.P. with the onset of the early glacial unit MIS 5d. The age of the stage is determined by correlation to uranium-thorium dates of raised coral reefs. The most detailed proxy record of interglacial climate is found in the Vostok ice core where the temperature reached current levels 132,000 yr ago and continued rising for another two millennia. Approximately 127,000 yr ago the Eemian mixed forests were established in Europe. They developed through a characteristic succession of tree species, probably surviving well into the early glacial stage in southern parts of Europe.

The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. between the West Greenland Current (WGC) and the West Greenland ice sheet. 30Changes in the fauna reveal significant variations in the water mass properties 31(temperature and salinity) of the WGC through time. to obtain the interaction between oceanographic variability and ice sheet behaviour. 70The modern hydrographic conditions of the region are dominated by the West 71Greenland Current (WGC, Figure 1). water productivity in the area (e.g. Hansen et al., 1999; Levinsen et al., 2000). In The relative abundance (%) of the dominant agglutinated and calcareous 228 species based on the total assemblage over the last 7.3 ka BP is presented in Figure 229 3. Based on changes within the total assemblage, along with changes in AtlW and 230AW groupings, an informal subdivision into three zones (A-C) has been made. The rapidly from c. 1.6 ka BP, reaching peak abundance of about 30% (Figure 4). 258Subsequently, from c. 1.6 to 1.3 ka BP, a slight reduction in abundance of this group 282In zone C, we observe a rise in AW species, in particular E. excavatum f. 283clavata, but also a minor increase in I. helenae, reaching a peak at c. 2.7 ka BP declines through this interval, although a sudden peak in abundance is seen at c. species (e.g. E. excavatum f. clavata) at c. 1.8 ka BP. 289The most prominent feature in the uppermost part of the record is the abrupt 290 decrease of E. excavatum f. clavata, I. norcrossi and C. reniforme from about 0.9 ka 291BP onwards, implying a change to harsher environmental conditions than previously. influence from the GIS and regional ocean forcing will be discussed below. BP (e.g. Long and Roberts, 2002; Long and Roberts, 2003; Lloyd et al., 2005; Young 312 et al., 2011). 313Strong melting from the GIS, translated to runoff into the ocean, is reported 314 between 8 and 6 ka BP (Alley and Anandakrishnan, 1995), and is thought to be in 315 response to atmospheric forcing, i.e. pronounced temperature rise over the GIS 316( Dahl-Jensen et al., 1998; Vinther et al., 2009). In addition to this proposed Iceland during this time interval (e.g. Knudsen et al., 2008b). 388[16]Already after 6 ka BP, we observe decreasing current strength of the WGC at 389 the coring site by decreasing sand content to about 15% at 4.0 ka BP (Figure 6c). 390The reduced flow speed of the WGC registered at the core site does not affect the 391 relative warmth of the WGC, as shown by the dominance and high concentration of 392 the AtlWcalc group at that time ( Figure 6d). We assume that th...

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Owing to the lack of absolutely dated oceanographic information before the modern instrumental period, there is currently significant debate as to the role played by North Atlantic Ocean dynamics in previous climate transitions (for example, Medieval Climate Anomaly-Little Ice Age, MCA-LIA). Here we present analyses of a millennial-length, annually resolved and absolutely dated marine δ18O archive. We interpret our record of oxygen isotope ratios from the shells of the long-lived marine bivalve Arctica islandica (δ18O-shell), from the North Icelandic shelf, in relation to seawater density variability and demonstrate that solar and volcanic forcing coupled with ocean circulation dynamics are key drivers of climate variability over the last millennium. During the pre-industrial period (AD 1000–1800) variability in the sub-polar North Atlantic leads changes in Northern Hemisphere surface air temperatures at multi-decadal timescales, indicating that North Atlantic Ocean dynamics played an active role in modulating the response of the atmosphere to solar and volcanic forcing.