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The oceanic system has been rapidly changing under human-induced climate change that is taking place at unprecedented rates. The paleoclimate archive of the last two millennia is often adopted to discern the ongoing anthropogenic global warming from the pre-industrial natural climate variability. The Mediterranean Sea is an especially critical system, being particularly affected by climate change. A common group of marine unicellular planktonic calcifiers, coccolithophores, are forming calcite plates, coccoliths. When reaching the sediments, they have been employed as a proxy in many paleoenvironmental reconstructions and are increasingly used in the last centuries. Recent studies indicate a subtle response to historical climate changes, except for primary productivity switches during the Little Ice Age and, most importantly, across the Industrial age. In this work, we use coccolith decadal-scale resolution data from core HER-MC-MR3.3, recovered in the Balearic Sea, exploring their variability over the pre-industrial age, from 700 BCE to 1740 CE. Results are compared to planktonic foraminifera stable isotopes, planktonic foraminiferal assemblages, alkenone-derived SSTs and foraminiferal Mg/Ca-derived SSTs, previously acquired in the same sediment core. Abundance variations in coccolith assemblages, expressed as Shannon-Wiener diversity H-index changes or as trends and fluctuations in ecological groups are associated with historical climate changes, among others the Medieval Climatic Anomaly and the Little Ice Age, indicating repeated modifications in surface water conditions, in response to hydrological and atmospheric changing patterns. A tight relationship between deep nutricline and upper water column stratified conditions, derived from high abundance of Florisphaera profunda, and high solar irradiation levels is established. The solar activity fingerprint in the F. profunda distribution pattern is further assessed by spectral analysis, with the emergence of significant periodicities observed in solar activity proxies, among others the well-known de Vries-Suess cycle. Finally, we notice small but statistically significant abundance fluctuations in holococcoliths (solution susceptible coccolith forms) that may be tied to their enhanced preservation during increased rainfall in western Europe. This implies the advection of westerlies and long-lasting blocking events that may have promoted deep-water formation and seafloor ventilation during this time. The comparison with sedimentological proxies of bottom current strength shows some inconsistencies but still defines variable and intermittent deep-water formation rates in the Gulf of Lions over the pre-industrial period.

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

We present a high-resolution paleoclimatic reconstruction of the last four millennia from a shallow water marine record recovered in the central Tyrrhenian Sea (Gulf of Gaeta) based on planktonic foraminifera and pollen records combined with oxygen stable isotope, tephrostratigraphic and magnetostratigraphic analysis. Paleoclimatic events have been recognised and discussed within the following time in intervals: Eneolithic (base of the core- 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). Within these time intervals, the proxy records document short-term climate oscillations well correlated with other records from Mediterranean marine areas (Alboran Sea, Gulf of Taranto, Adriatic Sea, and Ionian Sea). The long term trend in oxygen isotopic record obtained from the planktonic foraminiferal species Globigerinoides ruber (?18OG.ruber) has an antithetic correlation with the North Atlantic Oscillation (NAO) suggesting a strong northern hemisphere influence on the climate variability of the central Mediterranean region. The long term trend and amplitude oscillations of the ?18OG.ruber signal, the onset of main planktonic foraminiferal turnover from carnivorous to herbivorous-opportunistic species, and the consistent fluctuations of the pollen records document an important modification in climate system from the onset of the Roman Period up to the present-day. In addition, from ca. 500 AD upwards, the planktonic foraminiferal ?18O data, from marine records, shows a synchronous progressive long-term shift to more positive values superimposed to short-term oscillation, suggesting a Mediterranean secular scale signature in isotopic composition. From Maunder event to present day there is a progressive inversion in ?18O composition, suggesting the onset of the modern warm climate condition.

The retrieval of series of proxy data on the past climate will serve to acquire a deeper understanding of the climate system and a more accurate prediction of its future development, as a priority task for the scientific community. In particular, the analysis of climate data of the past is an essential tool for studying the dynamics of the earth's climatic system in conditions different from present ones, and irreplaceable for testing the validity of medium- and long-term forecasting models. The determination of the influence of anthropogenic impacts on the planet’s environment is predicated on a clear understanding of the natural ways in which the earth's climate responds to the complex set of external forcings. Therefore, in recent decades, many national and international research groups have focused attention on the study of the climate evolution in late-Quaternary sediments from the Mediterranean area. By virtue of its close relationship with continental masses subject to different climatic processes, the Mediterranean basin permits the documentation of climate evolution both globally and in the Northern Hemisphere. Finally, it is worth noting that shallow sea (continental shelf) areas are natural repositories for the monitoring of short-term climate change and anthropogenic impacts on the marine system. To make available information on climate history and environment yielded by marine sediments, this WP will be dedicated to analyzing and, where possible, collecting cores of marine sediments, especially those drilled in shallow sea environments, and focusing on climate dynamics in the Mediterranean over past centuries. During its course, the project will analyse and, where possible, sample marine sediment cores in continental shelf environments and in different sectors of the Mediterranean basin. Previous studies have indicated them as key sites for the identification of major short-term climate fluctuations, due to global and local forces active during the Quaternary and particularly in the past thousand years. In fact, the possibility of enriching the databases referring to this time interval (to date, still limited to the Mediterranean) will provide new working hypotheses for the implementation of numerical models that attempt simulate how the Mediterranean, in particular the marine-coastal sector, has responded to past climate dynamics (Medieval Warm Period / Little Ice Age transition, Little Ice Age, the Industrial Age, and Modern Warming). The cores obtained will be the focus of multidisciplinary studies involving national and international research groups.

A tephrochronological investigation was carried out at site ND14Q (1013 m of water depth), located in the southern Adriatic Sea, offshore the Gargano promontory. It was drilled in the frame of The NextData Project (www.nextdataproject.it, 2011-2013), focused on paleoclimate research. To obtain a composite and well preserved deep marine record, three cores were raised at the study site. Twelve primary cryptotephra and one tephra were analysed in terms of major-element content and correlated with a total of sixteen eruptive events. The studied materials display K-alkaline and subalkaline features pointing to a correlation with the Somma-Vesuvius, Campi Flegrei and Lipari Island (Aeolian Arc) volcanic activity occurred during the Late Pleistocene-Holocene. In detail, major marker tephra of the central Mediterranean have been recognized, among which the Phlegraean Neapolitan Yellow Tuff (ca. 15 ka), Pomici Principali (ca. 12 ka BP) and Astroni-Agnano-Monte Spina (ca. 4.2 ka - 4.4 ka BP) eruptions and, for the first time in this area, the Vesuvian 79 CE event. The very well preserved Mercato (ca. 9 ka BP) and Fiumebianco-Gabellotto (ca. 8.4 ka BP) cryptotephra have also been found in the sapropel S1 interval of the succession, which definitely records the last ca. 22 kyr (Pomici di Base tephra). A number of other Plinian and sub-Plinian events also occur and the availability of multiple cores provided new insights into their temporal relation such as between AP2 and Astroni 6 eruptions. The identification of tephra sourced by well-dated volcanic events, along with several AMS 14C age results, allowed an accurate chronological framework for the composite tephrostratigraphic record, thus providing accurate ages for those deposits with an uncertain correlative event. In addition, stratigraphic evidences in the core replicates at ND14Q site showed that several intervening factors affect preservation and traceability of cryptotephra deposits in the marine realm posing main critical issues on volcanological and paleoclimate research.

Reconstruction of last millennia Sea Surface Temperature (SST) evolution is challenging due to the difficulty retrieving good resolution marine records and to the several uncertainties in the available proxy tools. In this regard, the Roman Period (1 CE to 500 CE) was particularly relevant in the socio-cultural development of the Mediterranean region while its climatic characteristics remain uncertain. Here we present a new SST reconstruction from the Sicily Channel based in Mg/Ca ratios measured on the planktonic foraminifer Globigerinoides ruber. This new record is framed in the context of other previously published Mediterranean SST records from the Alboran Sea, Minorca Basin and Aegean Sea and also compared to a north Hemisphere temperature reconstruction. The most solid image that emerges of this trans-Mediterranean comparison is the persistent regional occurrence of a distinct warm phase during the Roman Period. This record comparison consistently shows the Roman as the warmest period of the last 2 kyr, about 2 °C warmer than average values for the late centuries for the Sicily and Western Mediterranean regions. After the Roman Period a general cooling trend developed in the region with several minor oscillations. We hypothesis the potential link between this Roman Climatic Optimum and the expansion and subsequent decline of the Roman Empire.

Globorotalia truncatulinoides oscillations have been recorded from different marine sediment cores collected in the central and western Mediterranean Sea. The abundances of this species over the last 500 yrs. demonstrates its potential value as bio-indicator of particular oceanographic condition during the Maunder Minimum (MM) event of the Little Ice Age (LIA). The comparison between the G. truncatulinoides abundance patterns of the Balearic Basin, central and south Tyrrhenian Sea and central and eastern Sicily Channel allows to highlight a similar response of this species during the MM event in the central-western Mediterranean Sea. The ecological meanings of this species and its peculiar high abundance percentages in the total assemblages suggest the development of enhanced vertical mixing conditions during MM winter season with a strong advection of nutrients from the nutrient-rich deeper layers and enhances the productivity levels in the mixed layer. The intensified vertical mixing could be linked to persistence of an atmospheric blocking event recorded by several authors during the MM.

A new marine pollen record from SE Sicily is presented. The pollen study was done at a sub-decadal resolution to assess the role and extent of human impact in driving regional environmental and land cover changes over the last four hundred years. The combination of palaeoecological evidence and historical documents provides a detailed report of the main ecological dynamics in relation to socio-economic events, past land use, and land management regulations in Sicily. Our palaeovegetational reconstruction reveals a remarkably stable landscape, preserved by traditional land use practices that have persisted through the long-lasting feudal history of Sicily. After centuries of human-induced environmental stability, an abrupt change in vegetation structure occurred around 1950 AD, reflecting the modern land use policies and agricultural reforms following the Second World War. This vegetational breakpoint in SE Sicily corresponds to a suggested date for the onset of the Anthropocene. (C) 2021 Elsevier B.V. All rights reserved.

We present a high-resolution paleoclimatic and paleoenvironmental reconstruction of the last five millennia from a shallow water marine sedimentary record from the central Tyrrhenian Sea (Gulf of Gaeta) using planktonic foraminifera, pollen, oxygen stable isotope, tephrostratigrapy and magnetostratigrapy. This multiproxy approach allows to evidence and characterize nine time intervals associated with archaeological/cultural periods: Eneolithic (base of the core–ca. 2410 BCE), Early Bronze Age (ca. 2410 BCE–ca. 1900 BCE), Middle Bronze Age–Iron Age (ca. 1900 BCE–ca. 500 BCE), Roman Period (ca. 500 BCE–ca. 550 CE), Dark Age (ca. 550 CE–ca. 860 CE), Medieval Climate Anomaly (ca. 860 CE–ca. 1250 CE), Little Ice Age (ca. 1250 CE–ca. 1850 CE), Industrial Period (ca. 1850 CE–ca. 1950 CE), Modern Warm Period (ca. 1950 CE–present day). The reconstructed climatic evolution in the investigated sedimentary succession is coherent with the short-term climate variability documented at the Mediterranean scale. By integrating the planktonic foraminiferal turnover from carnivorous to herbivorous–opportunistic species, the oxygen isotope record and the pollen distribution, we document important modification from the onset of the Roman Period to the present-day. From ca. 500 CE upwards the documentation of the cooling trend punctuated by climate variability at secular scale evidenced by the short-term δ 18 O is very detailed. We hypothesise that the present day warm conditions started from the end of cold Maunder event. Additionally, we provide that the North Atlantic Oscillation (NAO) directly affected the central Mediterranean region during the investigated time interval.