High‐frequency climate linkages between the North Atlantic and the Mediterranean during marine oxygen isotope stage 100 (MIS100)

Abstract

[1] High-resolution records of Mediterranean and North Atlantic deep-sea sediments indicate that rapid changes in hydrology and climate occurred during marine oxygen isotope stage 100 (MIS100) (at $2.52 Ma), which exhibits characteristics similar to late Pleistocene Dansgaard-Oeschger, Bond cycles and Heinrich events. As in the late Pleistocene, North Atlantic oceanographic and atmospheric changes were probably transmitted into the Mediterranean by some combination of surface water inflow and Atlantic-Mediterranean atmospheric pressure gradients. Our data suggest that the mechanism(s) responsible for sub-Milankovitch and millennialscale climate oscillations were the same over at least the past 2.6 Ma, notwithstanding the transition from the 41-kyr-dominated glacial cycles of the late Pliocene to the 100-kyr cycles of the late Pleistocene.

Late Pliocene changes in the North Atlantic Current

“…4), comparable to the glacial conditions of the middle and late Pleistocene (McIntyre et al, 1972;Stein et al, 2009;Villanueva et al, 2001). Such interpretation is supported by evidence from Site 607 with (1) an increase in IRD during glacials from MIS G16 onwards (Kleiven et al, 2002, updated to LR04 ages), (2) the appearance of larger sized IRD during MIS 100 and 98 , and (3) occurrence of Heinrich(-like) events during MIS 100 (Becker et al, 2006). This all indicates that during peak glacial conditions icebergs could travel as far south as 41°N and accounts for a changed North Atlantic surface circulation, including a weakened influence of the NAC and proximity of the AF at Site U1313 during glacial periods.…”

Mediterranean Outflow Water variability during the Early Pleistocene

“…This suggests that the flow strength of MOW was probably directly modulated by precession during the Early Pleistocene, aligning with previous findings based on Zr / Al ratios at Site U1389 from the Late Pleistocene . In fact, a strong processional influence was also shown for δ 18 O records from the eastern Mediterranean Sea (ODP site 967 and 969) and the midlatitude North Atlantic during MIS 100 to MIS 96 (Becker et al, 2005(Becker et al, , 2006. For the Late Pleistocene, an inverse relationship was found between precession and MOW dynamics Kaboth et al, 2016).…”

Low-latitude climate variability in the Heinrich frequency band of the Late Cretaceous greenhouse world

“…Cycles with similar periods are not restricted to the last glacial, but are also found in δ 18 O and other proxy records of marine isotope stages (MIS) 96-100 at ∼ 2.4 Ma (Becker et al, 2005(Becker et al, , 2006, though these lack the typical Heinrich event signature (Bond et al, 1992; results ODP Leg 162/171 IODP 303). Our observation is in agreement with the interpretation of Heinrich events being controlled by low-latitude climate changes induced by a non-linear response to the precession cycle between the tropics.…”