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A marine sediment core from the western Mediterranean provides a new highresolution 4,500-year record of palaeomagnetic secular variation and relative palaeointensity. In 2013, the 7.1-metre C5 core was recovered from the Tyrrhenian Sea as part of the NextData climate data project. The coring site, 15 km offshore from the Volturno river mouth, is well-located to record combined marine and terrestrial palaeoclimatic influences, and the fine-grained, rapidly deposited sediments are effective palaeomagnetic recorders. We investigate the palaeomagnetic field direction ACCEPTED MANUSCRIPT Downloaded from http://sp.lyellcollection.org/ at Universita Napoli Federico II on June 8, 2020 and strength recorded in the core, which provide a valuable high-resolution record of Holocene geomagnetic variation in the area. Using rock magnetic techniques, we constrain the magnetic mineralogy of the studied sediments and confirm their suitability for palaeomagnetic analysis. Palaeomagnetic declination and inclination records were determined by stepwise alternating-field demagnetization, and relative palaeointensity estimates were obtained based on normalization to anhysterestic and isothermal remanent magnetization and to magnetic susceptibility. The age of the core is wellconstrained with a tephro- and biostratigraphic age model, and its magnetic records are compared with relevant core and model data for the region, demonstrating that our record is compatible with previous results from the area. An automated curve matching approach is applied to assess the compatibility of our data with the existing secular variation path for the Mediterranean area

The history of vegetation in the Italian peninsula during the last 2000 years was shaped by a complex interplay of several factors, including the history of human societies, changes in land use, and the succession of climate events. In order to disentangle these factors, we present a multidisciplinary record from a marine core collected in the Gulf of Gaeta, interpreted in the light of other palaeoenvironmental records from Tyrrhenian Italy. Pollen records, complemented by new data on Non-Pollen Palynomorphs (NPPs) and microcharcoal, are used to reconstruct changes in the vegetational landscape, stock-breeding activities, fire, and land use. Foraminiferal and oxygen isotope data provide independent information on climate changes. NAO-index and sunspot data support the interpretation of changes in atmospheric circulation. In this paper, by examining the effect of climate and human activity on the landscape during a series of periods of the last 2000 years, representing cultural or climate phases (Roman Period, Dark Ages, Medieval Climate Anomaly, Little Ice Age, and Modern Period), we found that human impact produced a general and progressive decline of forest vegetation. However, irrespective of the societal cultural phase, forest declines occurred when negative NAO oscillations induced dry climate, especially during sunspot minima

A new high resolution pollen, planktonic foraminiferal and oxygen isotopes record from a shallow water marine sedimentary core from the central Tyrrhenian Sea (Gulf of Gaeta) provides information on vegetation and climate changes occurred in the central Mediterranean region during the last 5000 cal. years BP (Margaritelli et al., 2016). Nine time intervals characterized by clear vegetation and climate changes and associated with archaeological/cultural periods have been described: Eneolithic (ca. 3080- ca. 2410 BC), Early Bronze Age (ca. 2410 BC–ca. 1900 BC), Middle Bronze Age-Iron Age (ca. 1900 BC–ca. 500 BC), Roman Period (ca. 500 BC–ca. 550 AD), Dark Age (ca. 550 AD–ca. 860 AD), Medieval Climate Anomaly (ca. 860 AD–ca. 1250 AD), Little Ice Age (ca. 1250 AD–ca. 1850 AD), Industrial Period (ca. 1850 AD–ca. 1950 AD), Modern Warm Period (ca. 1950 AD–present day). In this paper we aim to characterize the major vegetation changes influenced by climate and human impact.

This study presents the reconstructed evolution of sea surface conditions in the central-western Mediterranean Sea during the late Holocene (2700 years) from a set of multi-proxy records as measured on five short sediment cores from two sites north of Minorca (cores MINMC06 and HER-MC-MR3). Sea surface temperatures (SSTs) from alkenones and Globigerina bulloides Mg / Ca ratios are combined with δ18O measurements in order to reconstruct changes in the regional evaporation–precipitation (E–P) balance. We also revisit the G. bulloides Mg / Ca–SST calibration and re-adjusted it based on a set of core-top measurements from the western Mediterranean Sea. Modern regional oceanographic data indicate that Globigerina bulloides Mg / Ca is mainly controlled by seasonal spring SST conditions, related to the April–May primary productivity bloom in the region. In contrast, the alkenone–SST signal represents an integration of the annual signal. The construction of a robust chronological framework in the region allows for the synchronization of the different core sites and the construction of “stacked” proxy records in order to identify the most significant climatic variability patterns. The warmest sustained period occurred during the Roman Period (RP), which was immediately followed by a general cooling trend interrupted by several centennial-scale oscillations. We propose that this general cooling trend could be controlled by changes in the annual mean insolation. Even though some particularly warm SST intervals took place during the Medieval Climate Anomaly (MCA), the Little Ice Age (LIA) was markedly unstable, with some very cold SST events mostly during its second half. Finally, proxy records for the last centuries suggest that relatively low E–P ratios and cold SSTs dominated during negative North Atlantic Oscillation (NAO) phases, although SSTs seem to present a positive connection with the Atlantic Multidecadal Oscillation (AMO) index.

Mediterranean Geoarchaeology Workshop, Shaping the Mediterranean basin: islands, coastlines and cultures across time

A high-resolution integrated study, which includes tephrochronology (tefra layer associated to 1906 AD Vesuvius event) and radionuclide dating method (210Pb and 137Cs), has been performed in a super-expanded marine record (sedimentation rate of 0.47 cm/yr) from the continental shelf of the Gulf of Gaeta (central eastern Tyrrhenian Sea). Planktonic foraminifera, calcareous nannofossils, pollens and oxygen stable isotope data performed on Globigerinoides ruber, revealed environmental changes occurred during the last two centuries. In detail we recognise four paleoclimatic changes. From ca. 1800 to ca. 1865 AD, d18O G. ruber signal combined with evidences of abundance increase of planktonic foraminifera Globoratialia inflata and G. truncatulinoides and of calcareous nannofossils Emiliana huxley document cold-temperate phase. Between ca. 1865 and ca. 1882 AD, d18O G. ruber record document a short warm interval associated with a turnover from carnivorous to herbivorous-opportunistic planktonic foraminiferal species and an increase in abundance of calcareous nannofossil Florisphaera profunda. At ca. 1935 AD, d18O G. ruber data indicate a gradually warming, concomitant an evident turnover from carnivorous to herbivorous-opportunistic planktonic foraminiferal species, and associated to the increase of calcareous nannofossil F. profunda. From ca. 1950 AD to the present day the warm phase documents a further strong increase in G. ruber alba, G. quadrilobatus and F. profunda abundances. The pollen analysis carried out on the same core revealed a two-step increase in arboreal vegetation, this is mostly related to a rise of Olea, Quercus evergreen and riparian trees (Alnus and Salix) from ca. 1882 AD, and increase in conifers (Pinus and Cupressaceae) from ca. 1980 AD. The short lived warm interval documented by d18O between ca. 1865 and ca. 1882 AD may triggered the increase in Olea and the coeval general decrease in deciduous trees. Among herbs, Cyperaceae, along with ferns, show a progressive decline in the upper part of the record, especially from 1935 to the present, suggesting a reduction of wetlands. Since 1920 AD, significant frequencies of dinoflagellate cysts may reflect both a nutrient loading and temperatures increases, as also documented by d18O and micropalaeontological records

A new high-resolution pollen record, spanning the last five millennia, is presented from the Gulf of Gaeta (Tyrrhenian Sea, central Italy), with the aim of verifying if any vegetation change occurred in the central Mediterranean region in relation to specific well-known global and/or regional climate events, including the 4.2 ka event, the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA), and to detect possible vegetation changes related to still under-investigated climate signals, for example the so-called “Bond 2” cold event around 2.8 ka BP. The vegetation dynamics of the Gaeta record shows a recurrent pattern of forest increase and decline punctuating the mid- and late Holocene. When the timing of these patterns is compared with the climate proxy data available from the same core (planktonic foraminifera assemblages and oxygen stable isotope record) and with the NAO (North Atlantic Oscillation) index, it clearly appears that the main driver for the forest fluctuations is climate, which may even overshadow the effects of human activity. We have found a clear correspondence between phases with negative NAO index and forest declines. In particular, around 4200 cal BP, a drop in AP (Arboreal Pollen) confirms the clearance recorded in many sites in Italy south of 43°N. Around 2800 cal BP, a vegetation change towards open conditions is found at a time when the NAO index clearly shows negative values. Between 800 and 1000 AD, a remarkable forest decline, coeval with a decrease in the frequencies of both Castanea and Olea, matches a shift in the oxygen isotope record towards positive values, indicating cooler temperatures, and a negative NAO. Between 1400–1850 AD, in the time period chronologically corresponding to the LIA (Little Ice Age), the Gaeta record shows a clear decline of the forest cover, particularly evident after 1550 AD, once again in correspondence with negative NAO index. © 2017 Elsevier Ltd