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  • Overall objectives in the EU GO project are to assess the promising potential of seismic imaging for physical oceanography, in view of its combination of fine resolution and coverage unmatched by conventional oceanographic measurements. D318 was to provide the means of assessment by obtaining a unique, comprehensive, oceanographic and seismic dataset at the same time and place. Specific objectives for R.R.S. Discovery cruise 318a were to deploy four ADCP moorings, three adjacent temperature-logger moorings and STABLE, in an L-shape array in 750-1000m depth east of Portimao Canyon, carrying out adjacent CTD stations, deploy two OBH moorings, carry out seismic sections using the Ifremer high-frequency air-guns and streamer, accompanied by regular XBT and less frequent XCTD casts. In addition underway data was logged including ship-borne ADCP, surface temperature and salinity, meteorology, gravity and magnetics (to test new NERC magnetometers).

  • Overall objectives in the EU GO project are to assess the promising potential of seismic imaging for physical oceanography, in view of its combination of fine resolution and coverage unmatched by conventional oceanographic measurements. D318 was to provide the means of assessment by obtaining a unique comprehensive oceanographic and seismic dataset at the same time and place. Specific objectives for R.R.S. Discovery cruise 318b were to (i) recover four ADCP moorings, three adjacent temperature-logger moorings and STABLE, from 750-1000m depth east of Portimao Canyon (ii) perform deep water CTD casts (iii) carry out seismic sections using the NMF supplied Bolt airgun and streamer, accompanied by regular XBT and less frequent XCTD casts, iv) work with MV Poseidon to test novel seismic data acquistion strategies. In addition underway data was logged including ship-borne ADCP, surface temperature and salinity, meteorology, gravity and magnetics (to test new NERC magnetometers).

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    Operational configuration of ROMS (Regional Ocean Modeling System) off NorthWest Iberia. In this configuration, two grids are nested during online execution. Data from the coarser (4 km horizontal resolution) 236 x 181 grid force the lateral open boundaries of the finer (~1.3 km) 312 x 167 embedded grid. Outputs at hourly and daily temporal resolution.

  • The research programme of Belgica campaign 2014/14 aimed at assessing the different biogeochemical processes controlling the carbon and nitrogen cycles in oligotrophic N.E. Atlantic waters. These cycles are essential components of the ‘biological Carbon Pump' by which part of atmospheric carbon dioxide is transferred to the ocean's interior. Our approach is based on the use of dual nitrate isotope measurements (natural abundance and enrichment experiments) to disentangle these various nitrogen processes in the marine environment, and in particular the process of diazotrophy by which atmospheric N2 is introduced into the oceanic fixed nitrogen reservoir. This input of ‘new' nitrogen should stand in balance with the denitrification process by which nitrogen is lost from the oceanic system. There are indications that the intensity as well as the geographical distribution of diazotrophic activity has been underestimated till date, in general. It is of particular interest to better document diazotrophic activity at latitudes of 38°N and northward, areas for which only few data are available. During the cruise we studied the different biogeochemical processes acting on the marine N-cycle, including N2 fixation, nitrate (NO3-), ammonium (NH4+) and nitrite (NO2-) uptake, nitrification, along a north-south section through the Gulf of Biscaye to Cape Finisterre and further south in open ocean waters along the Iberian peninsula till about 38°30'N. In addition, the effect of iron limitation on the nitrogen fixation and the nitrification processes was investigated.

  • The Western Iberian Margin (WIM) the area of interest for this cruise is located at the slope of the Southwest coast of Portugal (depths from 200 to 800 meters), where otter trawling is occurring on a continuous base, targeting Norway lobster (Nephrops norvegicus). The area includes fishing grounds with different levels of impact (from no fishing to intense trawling and fixed nets). We identified three main objectives for this sampling campaign: 1) Identify areas of high and low fishing intensity by means of side scan sonar and ROV exploration 2) Sample different areas/depths between 200 and 1000 m water depth for benthos with box corer and multiple corer 3) Collect sediments from the fished and the non‐fished site with box corer or multiple corer for onboard experiments in which different measures of ecosystem functioning will be measured 4) Collect colonization trays at food fall site with the ROV (uAveiro)