Climatic variability over the last 3000 years in the central - western Mediterranean Sea (Menorca Basin) detected by planktonic foraminifera and stable isotope records

摘要

The climate evolution of the last 2700 years in the central - western Mediterranean Sea has been reconstructed from marine sediment records by integrating planktonic foraminifera and geochemical signals. The results provide the characterization of six climatic phases: Balearic Bronze Age (BA), Roman Period (RP), Dark Age (DA), Medieval Climate Anomaly (MCA), Little Ice Age (LIA) and Industrial Period (IP). Paleoclimatic curve inferred from planktonic foraminifera associated with heavy values in delta O-18 Globigerinoides ruber during the BA document two cold intervals (spanning ca. 200 years) related to the Homeric and Greek solar minima. The dominance of Turborotalita quinqueloba -Globigerinita glutinata gr. and Globigerina bulloides during the RP suggest high fertility surface waters condition probably triggered by the increase in precipitation. During the DA, changes in the foraminiferal paleoclimate curve and oxygen isotope values display a cold -dry phase from 700 CE to the end of the DA (ca. 850 CE). This phase corresponds to the cold Roman N solar minimum and marks the beginning of a long - term cooling interval that terminates during the LIA. The MCA is characterized by mild climatic conditions, interrupted at ca. 1050 CE by a cold - dry event. The gradually increase in abundance of G. ruber white characterize the IP warm period.