Deltaic and Coastal Sediments as Recorders of Mediterranean Regional Climate and Human Impact Over the Past Three Millennia

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CLIMATIC VARIABILITY OVER THE LAST TWO MILLENNIA IN THE MEDITERRANEAN AREA: A REVIEW FROM MARINE PALEOARCHIVES

A review of the climatic variability over the last two millennia based on oxygen stable isotopic (G18OG. ruber) signals from different areas of the Mediterranean Basin (Minorca Basin, central and south Tyrrhenian Sea, Taranto Gulf, south Adriatic Sea and Israel) has been proposed. The correlation of data testifies an almost synchronicity of the identified climate events, suggesting an homogeneous response of the marine system to climate oscillations. This overall picture documents that the collapse of the Western Roman Empire results chronologically related to cold event Roman III solar minimum and that the Roman IV solar minimum (Dark Age), marks the transition vs a long term cooling trend, spanning ca. 1100 years, that culminates during the Maunder solar minimum (LIA). In addition, during the Maunder cold event, the strong increase in abundance of planktonic foraminifer Globlorotalia truncatulinoides, suggest the establishment of vertical mixing during the winter season induced by strong winds linked to an atmospheric blocking event

Late Holocene forest dynamics in the Gulf of Gaeta (central Mediterranean) in relation to NAO variability and human impact

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 Lt

Climatic variability over the last two millennia in the Mediterranean area. A review from marine paleoarchives

Una ricostruzione dettagliata delle oscillazioni climatiche riconosciute negli ultimi 2000 anni viene proposta tramite confronto di dati sugli isotopi stabili dell’ossigeno misurati sul foraminifero planctonico Globigerinoides ruber in diverse aree del Bacino del Mediterraneo (Bacino di Minorca, Mar Tirreno centrale e meridionale, Golfo di Taranto, Mar Adriatico Meridionale e Israele). Questa correlazione mostra che gli eventi climatici riconosciuti sono abbastanza sincroni e ben documentati nei vari settori del Bacino del Mediterraneo, indicando una risposta omogenea del sistema marino alle oscillazioni climatiche. Questo quadro di sintesi mostra che la caduta dell’Impero Romano d’Occidente coincide con l’evento freddo associato al minimo dell’attività solare Roman III e che il successivo minimo dell’attività solare Roman IV (Alto Medioevo) marca l’inizio di un lungo periodo di raffreddamento che dura circa 1100 anni e che termina durante il minimo solare del Maunder (Piccola Età Glaciale). Inoltre, durante la fase fredda del Maunder, il forte aumento in abbondanza del foraminifero planctonico Globorotalia truncatulinoides, suggerisce lo stabilizzarsi di un mixing verticale della colonna d’acqua durante il periodo invernale. Il perdurare di queste condizioni oceanografiche durante il Maunder è stato messo in relazione a eventi di “blocking” atmosferico che hanno innescato venti forti verso il Mediterraneo che possono aver attivato il mixing invernale delle acque.A review of the climatic variability over the last two millennia based on oxygen stable isotopic (18OG. ruber) signals from different areas of the Mediterranean Basin (Minorca Basin, central and south Tyrrhenian Sea, Taranto Gulf, south Adriatic Sea and Israel) has been proposed. The correlation of data testifies an almost synchronicity of the identified climate events, suggesting an homogeneous response of the marine system to climate oscillations. This overall picture documents that the collapse of the Western Roman Empire results chronologically related to cold event Roman III solar minimum and that the Roman IV solar minimum (Dark Age), marks the transition vs a long term cooling trend, spanning ca. 1100 years, that culminates during the Maunder solar minimum (LIA). In addition, during the Maunder cold event, the strong increase in abundance of planktonic foraminifer Globlorotalia truncatulinoides, suggest the establishment of vertical mixing during the winter season induced by strong winds linked to an atmospheric blocking event

A 4,500-year record of palaeomagnetic secular variation and relative palaeointensity from the Tyrrhenian Sea

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 are

New constraints on the Middle-Late Pleistocene Campi Flegrei explosive activity and Mediterranean tephrostratigraphy (∼160 ka and 110–90 ka)

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