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Sea surface temperatures (SSTs) and land-derived input time series were generated from the Gulf of Lions inner-shelf sediments (NW Mediterranean Sea) using alkenones and high-molecular-weight odd-carbon numbered n-alkanes (TERR-alkanes), respectively. The SST record depicts three main phases: a warm Early Holocene ( ~18±0.4 °C) followed by a cooling of ~3 °C between 7000 and 1000 BP, and rapid warming from ~1850 AD onwards. Several superimposed multi-decadal to centennialscale cold events of ~1 °C amplitude were also identified. TERR-alkanes were quantified in the same sedimentary horizons to identify periods of high Rhone River discharge and compare them with regional flood reconstructions. Concentrations show a broad increase from the Early Holocene towards the present with a pronounced minimum around 2500 BP and large fluctuations during the Late Holocene. Comparison with Holocene flood activity reconstructions across the Alps region suggests that sediments of the inner shelf originate mainly from the Upper Rhone River catchment basin and that they are primarily delivered during positive North Atlantic Oscillation (NAO). [ABSTRACT FROM AUTHOR]

Abstract: The Uk′ 37 record and coccolithophorid remains in sediments from the early Pliocene Sicilian Trubi Formation (Punta di Maiata) have been estimated to assess the possible influence of changes in the alkenone-producing coccolithophorids on the Uk′ 37–temperature relationship. The samples were dominated by small Reticulofenestra (R. minuta and R. minutula) and the C37 and C38 methyl and ethyl unsaturation ratios (Uk′ 37, Uk 38Me and Uk 38Et) were similar to those found in modern populations (E. huxleyi and G. oceanica). Those results suggest that the Early Pliocene small Reticulofenetrids had a similar temperature sensitivity of Uk′ 37 to that found in present day. These results support the application of the Uk′ 37 modern calibrations to reconstruct SST at least back in the Pliocene. [Copyright &y& Elsevier]

The atmospheric transport of organic pollutants over long distances and their effect on the biological cycles of the sea are two major questions of concern in environmental chemistry. These processes are of particular importance in the Mediterranean Sea because of its semi-enclosed characteristics, which determine the accumulation of the pollutants entering into the system. In order to get some insight into these processes a project (PHYCEMED), was developed for the evaluation of the atmospheric budget of organic and inorganic substances in the Western Mediterranean and for the investigation of the exchange mechanisms of these materials across the air/sea interface. A high volume air sampling system including a cascade impactor was placed on board of the R/V le Suroit for collecting the aerosols along several transects parallel to the French, Spanish and North-African coasts, facing areas of different population densities and industrial activities. The cruise was realised on October 1983 and the particulate material was fractionated into the following sizes: 7.2, 3.0, 1.5, 0.96, and 0.03 micron. Quantitative and qualitative analyses of the aliphatic and the aromatic hydrocarbons present in these fractions were performed by high resolution gas chromatography and gas chromatography-mass spectrometry.