Description: Quantitative calcareous plankton analyses have been performed at the Ocean Drilling Program Site 977 in the Alboran Sea through the mid-Brunhes interval (300–540 ka). The results evidence orbital-suborbital and millennial scale climate variability which primary reflects temperature change. The patterns of increase/decrease of coccolithophore and planktonic foraminifera warm water taxa reproduce the stage and substage climate variability in the planktonic δ18O in good agreement with other planktonic isotope records from Mediterranean Sea and Atlantic Ocean. Variable conditions, characterized by alternating cool nutrient-rich or warm and stable sea-surface waters, occurred during interglacial Marine Isotope Stage (MIS) 13 in response to high amplitude oscillations of insolation during obliquity maximum and to North Africa monsoon strength, influencing distribution of taxa. MIS 13a resulted warmer than MIS 13c based on the higher abundances of warm water taxa; they increase just after insolation maxima, suggesting a primary response of calcareous plankton to precessional orbital control. Following short-term warm (MIS 11e) and more humid (MIS 11d) phases, a climate optimum lasting about 16 kyr is recognized during MIS 11c, when major tropical-subtropical water arrival into the Alboran Sea occurred as evidenced by the presence of Trilobatus sacculifer. MIS 11c records unstable climate condition that persisted up to the late MIS 11, indicating multiple pulses of southward migrations of subpolar front following the full interglacial MIS 11c. Warm and oligotrophic conditions occurred during MIS 9 as during MIS 11, especially in MIS 9e, although without a climate optimum. Reduced abundance of warm water taxa and decrease of Globorotalia inflata highlight colder surface water conditions and decreased Atlantic-Mediterranean water exchange during glacials, especially during the prominent sea-level low-stand of MIS 12. Short-term prominent peaks of the polar-subpolar Neogloboquadrina pachyderma and Coccolithus pelagicus ssp. pelagicus, and additional key taxa preferring fresher and turbid water, together with minima in total Nannofossil Accumulation Rate and enhanced coccolith reworking, sustain a correlation with the North Atlantic Heinrich-type (Ht) events Ht1, Ht1a, Ht3, Ht4-6, thus documenting the sensitiveness of the Alboran Sea in recording European and Laurentide ice-sheet dynamics. The comparable chronology of most of these cold spells in the available Balearic and Ionian calcareous plankton records highlights that Atlantic melt water entering Alboran basin through Gibraltar Strait may have reached the central Mediterranean preserving some of its original polar signature.

Description: Quantitative coccolithophore analyses were performed in core MD01-2446, located in the mid-latitude North Atlantic, to reconstruct climatically induced sea-surface water conditions throughout Marine Isotope Stages (MIS) 14-9. The data are compared to new and available paleoenvironmental proxies from the same site as well as other nearby North Atlantic records that support the coccolithophore signature at glacial-interglacial to millennial climate scale. Total coccolithophore absolute abundance increases during interglacials but abruptly drops during the colder glacial phases and deglaciations. Coccolithophore warm-water taxa (wwt) indicate that MIS11c and MIS9e experienced warmer and more stable conditions throughout the whole photic zone compared to MIS13. MIS11 was a long-lasting warmer and stable interglacial characterized by a climate optimum during MIS11c when a more prominent influence of the subtropical front at the site is inferred. The wwt pattern also suggests distinct interstadial and stadial events lasting about 4-10 kyr. The glacial increases of Gephyrocapsa margereli-G. muellerae 3-4 µm along with higher values of Corg, additionally supported by the total alkenone abundance at Site U1313, indicate more productive surface waters, likely reflecting the migration of the polar front into the mid-latitude North Atlantic. Distinctive peaks of G. margereli-muellerae (〉 4 µm), C. pelagicus pelagicus, Neogloboquadrina pachyderma left coiling, and reworked nannofossils, combined with minima in total nannofossil accumulation rate, are tracers of Heinrich-type events during MIS12 and MIS10. Additional Heinrich-type events are suggested during MIS12 and MIS14 based on biotic proxies, and we discuss possible iceberg sources at these times. Our results improve the understanding of mid-Brunhes paleoclimate and the impact on phytoplankton diversity in the mid-latitude North Atlantic region.

Description: Sediment samples from the Ocean Drilling Program Site 976 (36°12.3'N, 4°18.8'W) were used to derive high temporal resolution δ¹⁸O G. bulloides, palynological (pollen and spores) and calcareous plankton (coccolithophores and foraminifera) records. This data set was used to trace the climate variability within late Marine Isotope Stage (MIS) 20 and MIS 19 in the area surrounding the Alboran Sea (western Mediterranean Sea).

Description: Planktonic foraminiferal assemblages were studied at high-resolution in core KC01B from the Ionian Sea. Quantitative analysis allowed us to distinguish the main climatic features and associated paleoceanographic changes, that occurred between Marine Isotopic Stages (MIS) 13 and 9 (~500-300 ka). MIS 12 and MIS 10 are characterized by relatively temperate conditions and an oligotrophic oceanographic regime in the early part and by colder conditions and nutrient supply in the sub-surface water masses in the upper part. During these intervals, small but distinct peaks of Neogloboquadrina pachyderma sinistral (sin) are detected at times of extremely negative values of the planktonic foraminifera paleoclimatic curve. Their co-occurrence with similar episodes in the Atlantic suggests that the climate in the Central Mediterranean was associated with north-Atlantic millennial-scale climate instability. MIS 11 and MIS 9 are dominated by surficial warm-water taxa. The climate optimum is reached in the middle part of each of these stages, as denoted by the presence of Globigerinoides sacculifer, and persists for approximately 20 and 6 ka during MIS 11 and MIS 9 respectively. This warming is not constant but is characterized by three distinct intervals with elevated winter temperatures and/or weak winter mixing. Distribution of Globigerina bulloides, Turborotalita quinqueloba and N. pachyderma dextral (dex) indicates that significant environmental changes occur across the transitions from glacial to interglacial MIS 12/MIS 11 (Termination V) and MIS 10/MIS 9 (Termination IV). The studied record documents a close linkage between Mediterranean climate evolution and higher- and lower-latitude climate change throughout MIS 13-9.