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Settling particles were collected using sediment traps deployed along three transects in the Lacaze-Duthiers and Cap de Creus canyons and the adjacent southern open slope from October 2005 to October 2006. The settling material was analyzed to obtain total mass fluxes and main constituent contents (organic matter, opal, calcium carbonate, and siliciclastics). Cascades of dense shelf water from the continental shelf edge to the lower continental slope occurred from January to March 2006. They were traced through strong negative near-bottom temperature anomalies and increased current speeds, and generated two intense pulses of mass fluxes in January and March 2006. This oceanographic phenomenon appeared as the major physical forcing of settling particles at almost all stations, and caused both high seasonal variability in mass fluxes and important qualitative changes in settling material. Fluxes during the dense shelf water cascading (DSWC) event ranged from 90.1 g m−2 d−1 at the middle Cap de Creus canyon (1000 m) to 3.2 g m−2 d−1 at the canyon mouth (1900 m). Fractions of organic matter, opal and calcium carbonate components increased seaward, thus diminishing the siliciclastic fraction. Temporal variability of the major components was larger in the canyon mouth and open slope sites, due to the mixed impact of dense shelf water cascading processes and the pelagic biological production. Results indicate that the cascading event remobilized and homogenized large amounts of material down canyon and southwardly along the continental slope contributing to a better understanding of the off-shelf particle transport and the internal dynamics of DSWC events.

In June 2009, 22 spectrometers from 14 institutes measured tropospheric and stratospheric NO2 from the ground for more than 11 days during the Cabauw Intercomparison Campaign of Nitrogen Dioxide measuring Instruments (CINDI), at Cabauw, NL (51.97° N, 4.93° E). All visible instruments used a common wavelength range and set of cross sections for the spectral analysis. Most of the instruments were of the multi-axis design with analysis by differential spectroscopy software (MAX-DOAS), whose non-zenith slant columns were compared by examining slopes of their least-squares straight line fits to mean values of a selection of instruments, after taking 30-min averages. Zenith slant columns near twilight were compared by fits to interpolated values of a reference instrument, then normalised by the mean of the slopes of the best instruments. For visible MAX-DOAS instruments, the means of the fitted slopes for NO2 and O4 of all except one instrument were within 10% of unity at almost all non-zenith elevations, and most were within 5%. Values for UV MAX-DOAS instruments were almost as good, being 12% and 7%, respectively. For visible instruments at zenith near twilight, the means of the fitted slopes of all instruments were within 5% of unity. This level of agreement is as good as that of previous intercomparisons, despite the site not being ideal for zenith twilight measurements. It bodes well for the future of measurements of tropospheric NO2, as previous intercomparisons were only for zenith instruments focussing on stratospheric NO2, with their longer heritage.

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.

Bottom trawling is a nonselective commercial fishing technique whereby heavy nets and gear are pulled along the seafloor, modifying the physical properties of seafloor sediments and altering natural sediment fluxes. Most studies addressing the physical disturbances of trawl gear on the seabed have been undertaken in coastal and shelf environments, where the capacity of trawling to modify the seafloor sediments coexists with high-energy natural processes driving sediment erosion, transport and deposition. Recent studies conducted on the Catalan margin have demonstrated that on continental slopes —where the sediment dynamics is less energetic— the reworking of the deep seafloor by bottom trawling produces periodic resuspension of surface sediments, and ultimately modifies the shape of the submarine landscape over large spatial scales. Trawling-induced sediment displacement and removal from fishing grounds causes the morphology of the deep seafloor to become smoother over time, reducing its original complexity. These results suggest that during the last decades, following the industrialization of fishing fleets, bottom trawling has become an important driver of deep seascape evolution Les dades presentades en aquest treball es van obtenir en el marc de diversos projectes de recerca: HERMIONE (226354 i CTM2010-11084-E), DOS MARES (CTM2010- 21810-C03), OASIS DEL MAR - Obra Social “la Caixa”, GRACCIE-CONSOLIDER (CSD2007- 00067) i REDECO (CTM2008-04973-E). Agraïm també el suport rebut per part del Govern Català als Grups de Recerca Consolidats (2009 SGR 899 i 1305) i l’ajut i assistència tècnica de les tripulacions dels vaixells oceanogràfics Hespérides, Sarmiento de Gamboa i García del Cid 8 pages, 9 figures Peer reviewed

Om alle belangen, zoals milieu, visserij, havens of tankervaart, rond een Europees zeegebied in goede banen te leiden is een aanpak nodig die de hele regio omvat. Er zou dus een gebiedsgerichte aanpak moeten komen voor bijvoorbeeld de hele Noordzee, de Oostzee of de Middellandse Zee. Regelingen op nationaal niveau alleen zijn onvoldoende. Op dit moment is het beleid en de regelgeving rond zeegebieden in en rondom Europa een lappendeken aan nationale, internationale en supranationale regelingen en instituties. Het antwoord op die lappendeken en onzekerheid is dat er een integrale en op een heel zeegebied gerichte beleidsaanpak onder supervisie van de EU van de grond moet komen, zegt prof. Van Tatenhove in zijn inaugurele rede The Tide is turning. The rise of legitimate EU marine Governance. Hij is voorzichtig optimistisch, nu er sinds enkele jaren zulke integrale gebiedsgerichte benaderingen zijn op het gebied van de bescherming van ecosystemen of van gemeenschappelijk visserijbeleid

Since the start of the HERMES and the HERMIONE projects, the margin of the Bay of Biscay has received special attention with respect to benthic ecosystems and sedimentary processes. The area is also known to be the historical cradle of cold-water coral studies by Joubin (1922) and Le Danois (1948). Already at that time the relationship between cold-water corals and fisheries were being discussed (with corals being a nuisance for fisheries!). Having performed previous work in the Whittard canyon (R/V Belgica 2006) and the Guilvinec canyon (R/V Belgica 2008), a joint marine geology and biology cruise was organized by the Renard Centre of Marine Geology and the Section of Marine Biology from Ghent University from 7 to 28 June 2010. The first leg (7-16 June, Zeebrugge-La Rochelle) focused on the Guilvinec canyon, while the second leg (19-28 June, La Rochelle-Zeebrugge) revisited several sites in the central Whittard canyon. The main objectives of this cruise were to (a) map and observe cold-water coral ecosystems on the canyon flanks with ROV Genesis, (b) obtain hydrographic data from CTD casts and water samples and (c) perform seabed multicoring for biology (descriptive and experimental research), biogeochemistry and sedimentology. In total, 23 scientists participated in this cruise, representing 10 institutes, among which were IFREMER, University College Cork and IFM-GeoMAR. The HERMIONE project is funded by the European Commission's Framework 7 Programme, under the theme "Environment (including climate change)". EC contract no. 226354. Peer reviewed 11 páginas