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A research cruise was organized on board the Italian National Research Council (CNR) R/V Urania to test the oil spill monitoring system developed during the PRogetto pilota Inquinamento Marino da Idrocarburi project (PRIMI, pilot project for marine oil pollution). For the first time, this system integrated in a modular way satellite oil spill detection (Observation Module) and oil spill displacement forecasting (Forecast Module) after detection. The Observation Module was based on both Synthetic Aperture RADAR (SAR) and optical satellite detection, namely SAR and Optical Modules, while the Forecast Module on Lagrangian numerical circulation models. The cruise (Aug. 6-Sep. 7, 2009) took place in the Mediterranean Sea, around Sicily, an area affected by heavy oil tanker traffic with frequent occurrence of oil spills resulting from illegal tank washing. The cruise plan was organized in order to have the ship within the SAR image frames selected for the cruise, at acquisition time. In this way, the ship could rapidly reach oil slicks detected in the images by the SAR Module, and/or eventually by the Optical Module, in order to carry out visual and instrumental inspection of the slicks. During the cruise, several oil spills were detected by the two Observation Modules and verified in situ, with the essential aid of the Forecasting Module which provided the slick position by the time the ship reached the area after the alert given by the SAR and/or optical imagery. Results confirm the good capability of oil spill SAR detection and indicate that also optical sensors are able to detect oil spills, ranging from thin films to slicks containing heavily polluted water. Also, results confirm the useful potential of oil spill forecasting models, but, on the other hand, that further work combining satellite, model and in situ data is necessary to refine the PRIMI system.

Malanotte-Rizzoli, Paola ... et. al.-- 76 pages, The importance of the Mediterranean Sea for the world ocean has long been recognized. First, the Mediterranean sea has a profound impact on the Atlantic ocean circulation and, consequently, on the global thermohaline conveyor belt. Maps of the 5 Mediterranean salty water tongue exiting from the Gibraltar strait at intermediate depths and spreading throughout the Atlantic interior are well known since the 1950s. Through direct pathways to the Atlantic polar regions or through indirect mixing processes, the salty Mediterranean water preconditions the deep convection cells of the polar Atlantic. There the North Atlantic Deep Water is formed which successively spreads throughout 10 the world ocean constituting the core of the global thermohaline circulation. Even more importantly, the Mediterranean Sea is a laboratory basin for the investigation of processes of global importance, being much more amenable to observational surveys because of its location in mid-latitude and its dimensions. Both the western and eastern basins in fact possess closed thermohaline circulations analogous to the 15 global conveyor belt. A unique upper layer open thermohaline cell connects the eastern to the western basin and, successively, to the north Atlantic through the Gibraltar strait. In it, the Atlantic water entering into Gibraltar in the surface layer, after travelling to the easternmost Levantine basin, is transformed into one of the saltiest water masses through air–sea heat and moisture fluxes. This is the salty water which, crossing the 20 entire basin in the opposite direction below the surface Atlantic water, finally exits from the Gibraltar strait at mid-depths. Both the western and eastern basins are endowed with deep/intermediate convection cells analogous to the polar Atlantic deep convection cells or to the intermediate mode water ones. Deep and intermediate water masses are therefore formed in differ25 ent sites of the entire basin. Because of their easily accessible locations, these convection cells are much more amenable to direct observational surveys and mooring arrays

A Mediterranean composite sedimentary record was analyzed for Ba/Ca ratios on carbonate shells of Orbulina universa planktonic foraminifer (Ba/Ca) carb providing the opportunity to study and assess the extent of freshwater inputs on the basin and possible impacts on its dynamics during the Tortonian to Recent period. A number of scanning electron microscope analyses and auxiliary trace element measurements (Mn, Sr, and Mg), obtained from the same samples, exclude important diagenetic effects on the studied biogenic carbonates and corroborate the reliability of (Ba/Ca) carb ratios in foraminifera calcite as indicators of seawater source components during the studied interval. A long-term trend with (Ba/Ca) carb values shifting from similar to 7 to 3 mu mol mol(-1) from the base of the Tortonian to the top of the Messinian is observed. The interval of the late Messinian salinity crisis, where biogenic carbonates are missing or strongly diagenized, represents a crucial passage not monitored in our record. At the base of the Pliocene, up to about 4.7 Ma, the (Ba/Ca) carb record shows a decreasing trend from similar to 4 mu mol mol(-1) stabilizing itself to an about constant value of 0.9 +/- 0.3 mu mol mol(-1) for the whole Plio-Pleistocene interval. These results suggest a dramatic change in the continental runoff values, up to similar to 3-16 times higher during part of the late Neogene (Tortonian-early Pliocene), with a possible profound modification in the physical dynamics of the Mediterranean basin. First-order mass balance equations used to estimate barium and salinity budgets in the Mediterranean Sea during the late Miocene-early Pliocene interval support the hypothesis of an active connection of the basin with the Paratethys region and of a definitive restriction at the base of the Pliocene after about 0.7 Ma from the well-known Messinian Lagomare phase. They also open intriguing scenarios on possible circulation shifts during the Neogene.

The aim of the present study was to evaluate the hazard from shipwrecks on communities by a holistic approach taking into account different effects on biological communities. Multibeam and Remotely Operated Vehicles surveys recorded ecological assessment of fish and benthic species on three shipwrecks flooded during the Second World War on Maerl beds habitats in the strait of Sicily. Pollution levels of a wide range of chemicals of ecotoxicological concern were also measured in sediments and in fish species from different trophic levels. Statistical analysis evidenced significant differences among pollutant levels between both sediments and fish collected in shipwreck sites and controls. Concerning fish, significant effects due to the vessel's cargo type and flooding position are recorded. In spite of that, our results underline that shipwrecks are also a hotspots of biodiversity and a habitat for preservation strategies in marine ecosystems that need to be monitored.

The study of planktonic organisms during abrupt climatic variations of the last glacial period (Dansgaard-Oeschger oscillations, D-O) may reveal important insights on climatic, oceanographic and biological interactions. Here we present planktic foraminifera and coccolithophore data collected at the Ocean Drilling Program Site 963 (Sicily Channel), with a mean sampling resolution of respectively 43.5 and 98.9. yr, over the interval between 70,000 and 20,000. yr ago. The paleoenvironmental reconstruction suggests that three different scenarios can be seen across each D-O cycle: 1. oligotrophic surface water and a deep thermocline for the early Interstadials; 2. a Deep Chlorophyll Maximum and coccolithophore winter/spring blooming in the late Interstadials; 3. reduced productivity together with the shallowing of the nutricline depth during Stadials and Heinrich events. The unique mode of productivity dynamics is corroborated by comparing our paleoecological results with those published from high-resolution cores in the Alboran Sea clearly indicating reduced trophic levels during Stadials and Heinrich events. Finally, we argue that the density contrast between the Atlantic water inflow and subsurface water may have affected productivity dynamics in such a large area. The strong vertical density gradient may have hampered the vertical convection of the water column, producing a negative effect on biological productivity, especially during Stadial phases. © 2013 Elsevier B.V.

The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910 ± 12, 1812 ± 18, 1725 ± 25 and 1580 ± 30 CE. A regional ocean hindcast links SCFR to enhanced deep-water production and in turn to strengthened Mediterranean thermohaline circulation. Independent evidence collected in the Aegean Sea supports this reconstruction, showing that enhanced bottom water ventilation in the Eastern Mediterranean was associated with each SCFR event. Comparison between the records and multi-decadal atmospheric circulation patterns and climatic external forcings indicates that Mediterranean circulation destabilisation occurs during positive North Atlantic Oscillation (NAO) and negative Atlantic Multidecadal Oscillation (AMO) phases, reduced solar activity and strong tropical volcanic eruptions. They may have recurrently produced favourable deep-water formation conditions, both increasing salinity and reducing temperature on multi-decadal time scales., Funding for this work was provided by the European Union’s Seventh Framework programme, FP7 under grant agreement no 265103 (MedSeA Project) and no 243908 (Past4FutureProject), Red CONSOLIDER GRACCIE CTM2014-59111-RED and the Past Global Changes (PAGES) project, which in turn received support from the US and Swiss National Science Foundations. G.J. thanks a postdoctoral grant (PD-036-2013) from the Comunitat Autonoma de les Illes Balears and the European Social Fund and a Ramón y Cajal contract (RYC-2013-14714). We acknowledge the support of the Generalitat de Catalunya to MERS (2014 SGR–1356) and Applied Geography (2014 SGR–1090).

Concentrations of rare earth elements (REE), Y, Th and Sc were recently determined in marine sediments collected using a box corer along two onshore–offshore transects located in the Strait of Sicily (Mediterranean Sea). The REE + Y were enriched in offshore fine-grained sediments where clay minerals are abundant, whereas the REE + Y contents were lower in onshore coarse-grained sediments with high carbonate fractions. Considering this distribution trend, the onshore sediments in front of the southwestern Sicilian coast represent an anomaly with high REE + Y concentrations (mean value 163.4 lg g 1) associated to high Th concentrations (mean value 7.9 lg g 1). Plot of shale-normalized REE + Y data of these coastal sediments showed Middle REE enrichments relative to Light REE and Heavy REE, manifested by a convexity around Sm–Gd–Eu elements. These anomalies in the fractionation patterns of the coastal sediments were attributed to phosphogypsum-contaminated effluents from an industrial plant, located in the southern Sicilian coast.

The Mediterranean Sea is a miniature ocean ideal to test the response of marine ecosystems to amplified orbital and suborbital climate changes. Here we present coccolith data from a Sardinia Channel gravity core (Arcose C_33) analysed over the last 145,000 years, with a mean resolution of about 900 years. The study highlights that regional phytoplankton assemblages underwent significant modifications between the penultimate glacial and the last interglacial, as well as between the last glacial and the Holocene. The N ratio palaeoproductivity index suggests reduced productivity levels and the development of a deep nutricline during the last interglacial and the Holocene. Within the last glacial period, many taxa exhibit abundance fluctuations that parallel oscillations in delta O-18 values of Globigerina bulloides tests. Heinrich events and stadials seem to be associated with drops in primary productivity levels, as already observed in the Alboran Sea and the Sicily Channel. A total of 19 ecobioevents were identified in the Sardinia Channel sediments, including abundance fluctuations of Emiliania huxleyi >4 mu m, Florisphaera profunda and Gephyrocapsa oceanica. The comparison of events across the Mediterranean Sea suggests that traceability applies to the Sicily Channel, Balearic and Tyrrhenian Seas, supporting the adoption of a common ecobiostratigraphic scheme. Less certain is the correlation with the Alboran Sea, although peaks of Helicosphaera carteri and Syracosphaera histrica during Heinrich events and stadials suggest similar nutrient dynamics in response to suborbital climatic variations in the Sicily Channel, southern Tyrrhenian and Alboran Seas. The traceability of events within eastern Mediterranean cores is strongly limited, possibly due to different physico-chemical properties and nutrient dynamics. (C) 2014 Elsevier B.V. All rights reserved. The Mediterranean Sea is a miniature ocean ideal to test the response of marine ecosystems to amplified orbital and suborbital climate changes. Here we present coccolith data from a Sardinia Channel gravity core (Arcose C_33) analysed over the last 145,000 years, with a mean resolution of about 900 years. The study highlights that regional phytoplankton assemblages underwent significant modifications between the penultimate glacial and the last interglacial, as well as between the last glacial and the Holocene. The N ratio palaeoproductivity index suggests reduced productivity levels and the development of a deep nutricline during the last interglacial and the Holocene. Within the last glacial period, many taxa exhibit abundance fluctuations that parallel oscillations in δ18O values of Globigerina bulloides tests. Heinrich events and stadials seem to be associated with drops in primary productivity levels, as already observed in the Alboran Sea and the Sicily Channel. A total of 19 ecobioevents were identified in the Sardinia Channel sediments, including abundance fluctuations of Emiliania huxleyi > 4 μm, Florisphaera profunda and Gephyrocapsa oceanica. The comparison of events across the Mediterranean Sea suggests that traceability applies to the Sicily Channel, Balearic and Tyrrhenian Seas, supporting the adoption of a common ecobiostratigraphic scheme. Less certain is the correlation with the Alboran Sea, although peaks of Helicosphaera carteri and Syracosphaera histrica during Heinrich events and stadials suggest similar nutrient dynamics in response to suborbital climatic variations in the Sicily Channel, southern Tyrrhenian and Alboran Seas. The traceability of events within eastern Mediterranean cores is strongly limited, possibly due to different physico-chemical properties and nutrient dynamics.

Rare earth element (REE) content in suspended and dissolved phases from the Strait of Sicily (Central Mediterranean Sea) has been measured. Vertical profiles of several dissolved REEs along the water column reflect the 3-D oceanographic features of the studied area and identifies the different water masses present there. Shale-normalized REE distribution patterns and derived parameters calculated for the suspended particulate show different atmospheric dust-surface inputs and their interactions with seawater. Finally, combined information from [La/Yb]N, ratios, REE/La ratios and Eu anomalies measured in the suspended particulate suggest an important contribution of volcanic materials from the Etna volcano and Saharan dust to the lithogenic fraction of the suspended particulate. © 2004 Taylor and Francis Ltd.

The Augusta basin, located in SE Sicily (southern Italy), is a semi-enclosed marine area, labelled as a highly contaminated site. The release of mercury into the harbour seawater and its dispersion to the blue water, make the Augusta basin a potential source of anthropogenic pollution for the Mediterranean Sea. A mass balance was implemented to calculate the HgT budget in the Augusta basin. Results suggest that an average of ∼0.073 kmol of HgT is released, by diffusion, on a yearly basis, from sediments to the seawater, with a consequent output of 0.162 kmol y(-1) to coastal and offshore waters; this makes the Augusta area an important contributor of mercury to the Mediterranean Sea. Owing to the geographical location of the Augusta basin, its outflowing shelf-waters are immediately intercepted by the surface Atlantic Ionian Stream (AIS) and mixed with the main gyres of the eastern Mediterranean Sea, thus representing a risk for the large-scale marine system.

New centennial-scale data of benthic foraminifera assemblages and of stable isotopes of foraminifera shells from the Sicily Channel, representative of surface and bottom waters, over the interval between about 140 and 110 kyr BP, are presented. During this period anoxia developed on the eastern Mediterranean basin and sapropel S5 deposited. Although anoxic sediments have not been deposited in the Sicily Channel, this area is strategic to study the character of intermediate waters, whose chemical-physical properties strongly precondition the eastern Mediterranean deep water formation. So far, no data from these water masses have been obtained, apart from the isotopic composition of shells of the planktonic foraminifera species Neogloboquadrina pachyderma which lives at about 200. m depth, thus quite far from the intermediate water core. We conclude that, although with a reduced rate, the flowing of intermediate waters coming from the eastern basin, together with the surface water masses with a clear western affinity, implies the maintenance of an anti-estuarine circulation pattern across the Sicily Channel and in the Mediterranean Sea, also during one of the most severe episodes of anoxia of the Late Pleistocene. © 2011 Elsevier B.V.

The Little Ice Age (LIA) is the last episode of a series of Holocene climatic anomalies. There is still little knowledge on the response of the marine environment to the pronounced cooling of the LIA and to the transition towards the 20th century global warming. Here we present decadal-scale coccolithophore data from four short cores recovered from the central Mediterranean Sea (northern Sicily Channel and Tyrrhenian Sea), which on the basis of 210Pb activity span the last 200–350 years. The lowermost part of the record of one of the cores from the Sicily Channel, Station 407, which extends down to 1650 AD, is characterized by drastic changes in productivity. Specifically, below 1850 AD, the decrease in abundance of F. profunda and the increase of placoliths, suggest increased productivity. The chronology of this change is related to the main phase of the Little Ice Age, which might have impacted the hydrography of the southern coast of Sicily and promoted vertical mixing in the water column. The comparison with climatic forcings points out the importance of stronger and prolonged northerly winds, together with decreased solar irradiance.

A multidisciplinary study was carried out on core C106 collected in the Salerno Gulf (southern Tyrrhenian Sea). Two tephra layers recovered in the core, N 18 O record of Globigerinoides ruber and Globigerina bulloides and seven 14 C calibrated ages provided the stratigraphic framework. The core sediments cover the last 28 kyr BP. Seismostratigraphic analysis of a high resolution acoustic profile, integrated by the dated core samples, allowed us to reconstruct the architecture and age of sedimentary bodies on the continental shelf. An integrated study based on different taxonomic groups (nannofossils, pteropods, foraminifera, and palynomorphs) provided palaeoclimatic trends, in agreement with changes in the isotopic composition of oxygen. The upper part of the Last Glacial period, the deglaciation phase and the Holocene were identified. Correlation between marine and continental records of palaeoenvironmental changes confirms a similar reconstruction of the last deglaciation as in the central and southern Mediterranean Sea. The Late Pleistocene^Holocene boundary was recognised at about 11.7 kyr BP. Between about 9.5 and 6 kyr BPand at 3.3 kyr BPsome warmer episodes were recorded. The measured lower isotopic values, together with some features of the fossil assemblages recorded from 9.5 to 6 kyr BP, may be related to the oceanographic setting that led to the deposition of Sapropel S1 in the Mediterranean basin. ; 2002 Elsevier Science B.V. All rights reserved.

The Gulf of Sirte is a largely unexplored area in the southernmost Mediterranean Sea.We are presenting here 2008 summer data on the distribution pattern of living coccolithophores, a main phytoplankton calcifying group, in 105 samples from 20 stations. The survey includes coastal and offshore stations, enabling us to provide indications on the dynamics of phytoplankton productivity in relation to oceanographic processes. The total coccosphere concentrations show higher values in the offshore stations and lower ones for coastal sites. Umbellosphaera tenuis, Emiliania huxleyi, Florisphaera profunda, Syracosphaera pulchra HOL (Calyptrosphaera oblonga) and Rhabdosphaera spp. dominate the assemblages. The coccolithophore community shows the typical vertical zonation, with K-strategist taxa (among others U. tenuis, Rhabdosphaera spp. and Discosphaera tubifera) in the upper 75 meters depth and Lower Photic Zone taxa, dominated by F. profunda, below. The latter species shows its maximum development in the Deep Chlorophyll Maximum layer, which occurs in the upper part of the Levantine Intermediate Water, where the nutrient content is higher than in the overlying layers. The mesoscale oceanographic circulation significantly affects the spatial and vertical distribution of coccolithophores, with the thermocline and halocline depth shaping the vertical zonation of coccolithophore taxa and resulting in a strong lateral gradient within the gulf: in the eastern sector, under the influence of the Gulf of Sirte anticyclone, the DCM is deeper and so is the occurrence of K-strategist taxa and F. profunda.