Enhanced climate instability in the North Atlantic and southern Europe during the Last Interglacial

• Published in: Nature Communications
• Main Authors: Tzedakis, P. C., Drysdale, Russell N., Margari, Vasiliki, Skinner, Luke C., Menviel, Laurie, Rhodes, Rachael H., Taschetto, Andréa Sardinha, Hodell, David A., Crowhurst, Simon J., Hellstrom, John C., Fallick, Anthony Edward, Grimalt, Joan O., McManus, Jerry F., Martrat, Belen, Mokeddem, Zohra, Parrenin, Frédéric, Regattieri, Eleonora, Roe, K., Zanchetta, Giovanni
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Nature 2018
• Subjects: Last interglacial; Interglacial; Greenland; North Atlantic
• Online Access: http://hdl.handle.net/10261/172977; https://doi.org/10.1038/s41467-018-06683-3

Considerable ambiguity remains over the extent and nature of millennial/centennial-scale climate instability during the Last Interglacial (LIG). Here we analyse marine and terrestrial proxies from a deep-sea sediment sequence on the Portuguese Margin and combine results with an intensively dated Italian speleothem record and climate-model experiments. The strongest expression of climate variability occurred during the transitions into and out of the LIG. Our records also document a series of multi-centennial intra-interglacial arid events in southern Europe, coherent with cold water-mass expansions in the North Atlantic. The spatial and temporal fingerprints of these changes indicate a reorganization of ocean surface circulation, consistent with low-intensity disruptions of the Atlantic meridional overturning circulation (AMOC). The amplitude of this LIG variability is greater than that observed in Holocene records. Episodic Greenland ice melt and runoff as a result of excess warmth may have contributed to AMOC weakening and increased climate instability throughout the LIG. © 2018, The Author(s). We thank A. Scrivner and C. Walmsley for assistance with foraminifer sample preparation and J. Rolfe and I. Mather for technical assistance with stable isotope measurements, M. Maslin and D. Thornalley for comments on an earlier version of the manuscript, A. Carlson and E. Galaasen for discussions and E. Galaasen and N. Irvali for providing the MD03-2664 data. V.M., K.R., L.C.S. and P.C.T. acknowledge support for the MD01-2444 study from UK-NERC project NE/G00756X/1 (to P.C.T. and L.C.S.). R.N.D., L.C.S., E.R., G.Z. and P.C.T. acknowledge support from Australian Research Council grant DP160102969 (to R.N.D.). L.M. acknowledges support from the Australian Research Council grant DE150100107. A.S.T. and J.H. are supported by the Australian Research Council (ARC). The numerical experiments were undertaken on the NCI National Facility at the ANU, Australia. B.M. acknowledges support from the CSIC-Ramón y Cajal postdoctoral ...