Offset timing of climate oscillations during the last two glacial‐interglacial transitions connected with large‐scale freshwater perturbation

Abstract

Th-dated speleothem timescale to ODP976 suggests glacial conditions in the Northeast Atlantic region were terminated abruptly and interglacial warmth was reached in less than a millennium. The early-MIS5e cooling and freshening at ODP976 coincided with similar changes at North Atlantic sites suggesting this was a basin-wide event. By analogy with T1, we argue that this was a YD-type event that was shifted into the early stages of the last interglacial period. This scenario is consistent with evidence from northern North Atlantic and Nordic Sea sites that the continuing disintegration of the large Saalian Stage (MIS6) ice sheet in Eurasia delayed the advection of warm North Atlantic waters and full-strength convective overturn until later stages of MIS5e.

The last interglacial (MIS 5e) cycle at Little Bahama Bank: A history of climate and sea-level changes

“…This age is in good agreement with many marine and speleothem records, dating a rapid poststadial warming and monsoon intensification to 129-128.7 ka (Galaasen et al, 2014;Govin et al, 2015;Jiménez-Amat and Zahn, 2015) coincident with the sharp methane increase in the EPICA Dome C ice core (Loulergue et al, 2008;Govin et al, 2012). Although we do not apply a specific age marker to frame the decline of the MIS 5e "plateau", the resulting decrease in 130 the percentage of warm surface-dwelling foraminifera of Globigerinoides genus as well as the initial increase in the planktic d…”

“…A corresponding cooling and freshening event -referred elsewhere as to a Younger Dryas type event -is captured in some high-and mid-latitude N. Atlantic records ( Bauch et al, 2012;Irvali et al, 2012;Schwab et al, 2013;Govin et al, 2014;Jiménez-Amat and Zahn, 2015;Zhuravleva et al, 2017a). Coherently with the Younger Dryas type cooling and the reduction/shallowing in the NADW, an increase in Antarctic Bottom Water formation is revealed in the Southern Ocean core data, arguing for existence of an "interglacial" 300 bipolar seesaw (Hayes et al, 2014).…”

Abrupt climate changes during Termination III in Southern Europe

“…The imprint of the δ 18 O differs between both events and only the S8.1 event is pointed out with extremely low values. The sudden arrival of fresh ( 18 O-depleted) meltwater to North Atlantic intermediate latitudes and entrance in the Mediterranean Sea would provide a mechanism to explain the low δ 18 O signal during S8.1 in an analogous way that occurred during T-I (Heinrich 1) and T-II (Heinrich 11) (26). Other records in the Iberian Peninsula have reported a similar isotopic response to the arrival of fresh water to North Atlantic (e.g., during the 8.2-ky event) (27) That event has more enriched δ 13 C values than S8.1, pointing out a lower vegetation activity in our area, in coherence with the record from Chinese caves with weaker monsoon in S8.2 with respect to S8.1 (Fig.…”

Aligning and synchronization of MIS5 proxy records from Lake Ohrid (FYROM) with independently dated Mediterranean archives: implications for DEEP core chronology

“…stable isotopes, Regattieri et al, 2014). Considering that marine chronologies, beyond the limit of radiocarbon dating methods, are often based on astronomical assumptions, it is now also common to transfer independently dated speleothems chronologies to marine records (Bar-Matthews et al, 2000;Almogi-Labin et al, 2009;Drysdale et al, 2007Drysdale et al, , 2009Grant et al, 2012;Ziegler et al, 2010;Hodell et al, 2013;Marino et al, 2015;Jiménez-Amat and Zahn, 2015). This can be somewhat problematic, as the assumption of synchronicity between speleothem and marine proxy records is not necessarily straightforward (e.g.…”

“…Moreover, different approaches to correlate chronologies from speleothem-based proxy records and marine proxies have been proposed (e.g. Drysdale et al, 2009;Ziegler et al, 2010;Grant et al, 2012;Marino et al, 2015;Jiménez-Amat and Zahn, 2015).…”