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    The overall aim of the UKSOLAS project DOGEE-SOLAS is the parameterization of air-sea gas exchange, which is a currently a major uncertainty in global modelling. RRS Discovery cruise D320 thus was primarily concerned with the measurement of air-sea gas transfer velocities and some of the important physical parameters that influence them through contributing to near surface turbulence, and other processes. In brief, specific cruise objectives were: 1. Determine open ocean gas transfer velocities through a number of dual-tracer releases (3He & SF6). 2. Investigate the role of surfactant in gas exchange through a targeted surfactant release in conjunction with (1). 3. Determine CO2 fluxes and transfer velocities, and make associated hydrographic and turbulence related measurements from autonomous ASIS (Air-Sea Interaction Spar) buoys. 4. Measure air-sea fluxes of CO2, sensible heat, latent heat and momentum using the AUTOFLUX automated sensor array 5. Measure underway, total gas tension, dissolved O2, and CO2 to obtain independent air-sea gas exchange estimates. 6. Make covariance and gas budgeting estimates of air-sea gas exchange using intelligent profiling Lagrangian floats. 7. Independently determine DMS fluxes and gas transfer velocities for comparison with CO2 to examine the role of gas solubility in gas transfer. 8. Deploy a spar buoy (NOC) for measurement of wave heights and bubble properties 9. Record and measure whitecap coverage and wave breaking coincident with the air-sea flux measurements using ship mounted cameras 10. Record key meteorological variables 11. Quantify flow distortion biases in the direct flux measurements via the use of established models. 12. Make biogas, surfactant and bacterial measurements in the surface microlayer and in the uppermost metres of the ocean using surface microlayer samplers, a remotely operated catamaran, and a near surface sampler. 13. Deploy an autonomous powered profiler (ASIP) for turbulence-related measurements in the mixed layer. Objectives 1-12 were all met. Unfortunately, due to mechanical failure and loss of ASIP, objective 13 was not realised.

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    The objective of cruise DY039 was to service the moorings of the RAPID 26°N project that are deployed to monitor the Atlantic Meridional Overturning Circulation. For each mooring instruments were recovered, data were downloaded and instruments were redeployed. A number of CTDs were made to calibrate the instruments from the moorings. In addition to the standard instruments used in previous years on the RAPID array, biogeochemical instruments were deployed for the ABC Fluxes project, along with some additional temperature sensors and ADCPs for the MerMeed project. During passage from Southampton to Tenerife trial CTDs were completed in international waters. After a short port call in Santa Cruz de Tenerife, departing on the 26th October work commenced on the eastern boundary sub-array comprising of moorings EBH4, EBH4L, EBH3, EBH2, EBH1, EBH1L, EBHi, EB1 and EB1L. A lander was deployed alongside EBHi to provide delayed-mode data telemetry through timed data pod release. Work on the MAR sub-array commenced on 7th November at mooring MAR3. The other moorings in this sub-array (MAR3L, MAR1, MAR1L, MAR2 and MAR0) were all completed by 12th November. The NOG mooring was also recovered and redeployed as part of the MAR sub-array servicing. Mooring WB6 was serviced on 19th November before transiting to Nassau for customs clearance. The remaining western boundary sub-array moorings (WBADCP, WBAL, WB1, WB2, WB2L, WBH2, WB4 and WB4L) were serviced between the 22nd November and the 30th November before docking in Nassau on the 1st December.

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    SHOM oceanographic cruise

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    SHOM cruise between Falmouth and Brest

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    Timing and frequency of landslide and gravity flow geohazards along the eastern North Atlantic continental margin This research cruise was a contribution towards the NERC strategic science programme (Oceans 2025). The main scientific objective was to improve our understanding of landslide and gravity flow geohazards along the eastern North Atlantic margin, in particular by studying event timing and frequency in the recent geological record. Special attention was being paid to geohazards that may potentially impact UK communities and infrastructure. Shallow piston coring of turbidite successions in deep basins produces the best record of recent (<50 kyrs) gravity flow events on adjacent margins (e.g. Weaver et al., 2000), but the availability of pre-existing data from the study area was patchy. Consequently, a key aim of JC027 was to 'fill the gaps' and recover cores from basins, or sections of basins, where data are urgently required. A total of 60 piston and megacores was successfully recovered during the cruise, from a series of lower canyon and basin floor environments. Shallow geophysical data, including subbottom profiles and hull-mounted multibeam bathymetry, were collected quasi-continuously during the cruise to define local environment around core sites. In complex areas, such as seafloor scours, Autosub6000 was deployed to collect high-resolution EM2000 multibeam bathymetry.

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    The major aims of Charles Darwin cruise 178 were to obtain: (i) 3D seismic imagery, video transects and swath bathymetry maps of mud volcanoes in the southern Gulf of Cadiz, (ii) video transects across suspected cold water coral reefs in the Alboran Sea, and (iii) 3D seismic imagery of submarine landslides in the Eivissa Channel, immediately east of the Balearic Islands in the western Mediterranean Sea. The cruise was in support of the EU Framework 6 'HERMES' project (Hotspot Ecosystem Research on the Margins of European Seas). A total of four 3D seismic cubes and 10 successful video transects were completed. Live chemosynthetic communities found on one mud volcano in the Gulf of Cadiz appear to indicate active methane seepage. Images of gas-charged sediments in areas of submarine landsliding in the Eivissa Channel appear to indicate a direct linkage between landsliding and fluid escape.

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    The objective of the cruise was to improve our understanding of biochemical processes in the near-surface and microlayer of the ocean. We examine gradients in major nutrient concentrations and cycling, production and consumption of key biogases and variability in biological communities between micro-layer, near -surface and deeper water, and between productive and oligotrophic waters along a transect from offshore oligotrophic to coastal upwelling waters off western Spain and Portugal. We also aimed to examine the influence of gradients in physical, biological and photochemical processes at or near the surface micro-layer on the transport of heat and bio-gases across the air-sea interface. Using near-real time satellite imagery of ocean colour in combination with continuous underway measurements of sea surface temperature and chlorophyll fluorescence we identified a suitable oligotrophic site ~25nm off the coast just north of the spain/Portugal border, and reached it on 21 st June and commenced scientific work. We then worked our way inshore via 4 more stations to an upwelling site where science work was concluded on 6th July. The vessel then returned to Falmouth, arriving on 9th July.

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    Objectives: To quantify marine halocarbon emission variability and latitudinal variation, characterise in situ open ocean atmospheric reactive iodine latitudinal variability and characterise oxidative chemistry perturbation due to oceanic emission of halogens from the Mauritanian upwelling region. Rationale: Transecting from the UK through Biscay, south past the west coast of Africa, through the Mauritanian upwelling, to pass Cape Verde simultaneous to the intensive deployment at the UK SOLAS Observatory on Sao Vicente, the measurements made on Discovery cruise D319 are intended to provide a detailed latitudinal characterisation of marine atmospheric halogen chemistry. This will feed validation and constraint data to regional and global models in projects linked to RHaMBLe. In addition the cruise will address a number of key scientific questions required to determine the global importance of iodine chemistry and to further our understanding of the controls of halogen chemistry in the remote ocean: i) How heterogeneous are the direct halogen sources and on what scale is the heterogeneity - does the upwelling region produce more or less halogens than the 'background' region? ii) What are the relative contributions of I atoms to the remote MBL from I2 and organic iodine? iii) Is sufficient iodine released to the remote MBL to sustain aerosol nucleation or to significantly affect the ozone budget and free radical populations? Measurement Description: Measured species included a variety of halocarbons in both water column and atmosphere and atmospheric boundary layer measurements of I2, OIO and IO by Broadband Cavity Enhanced Absorption Spectroscopy (BBCEAS). A compact version of the FAGE system, developed for the FAAM BAe-146, was deployed to provide measurements of IO or OH / HO2, permitting direct assessment of RHS-induced changes in the oxidising environment through the upwelling region. A range of trace gas monitors was simultaneously deployed to measure O3 and NOx. Aerosol number and size distribution measurements from 3 nm to 20 micron diameter were also made by a range of mobility (SMPS) and optical instrumentation, (OPC and FSSP). Additional aerosol measurements were provided as part of the NERC-funded ACMME project (PI Allan). Measurements of pigments in the surface waters were made by HPLC. Prevailing meteorological conditions were used to direct the cruise in terms of geographical positioning and measurement interpretation, e.g. i) exploitation of any broad flow connection between Cape Verde and the ship to interpret measurements as process studies and ii) identification of in- and out-of-plume conditions to contrast chemistry influenced and uninfluenced by emissions from the upwelling region.

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    The SCANS-II project aims at estimating the abundance of small cetaceans inhabiting shelf waters of the Atlantic margin, the North Sea and adjacent waters. Different methods will be used; ship-based monitoring is one of these. Data on abundance are essential to assess the impact of bycatch and other threats, and as input to management actions to ensure the favourable conservation status of these species. The project will develop a management framework to use such data. This will be centred on relatively simple but spatially explicit dynamic models tested by simulation to ensure robustness. An essential part of this long-term management is a robust cost-effective means of monitoring abundance between major SCANS-type surveys; the project will develop and test potential methods, and recommend a suite of monitoring protocols.The "BEL-COLOUR" aims at improving the theoretical basis and software tools for applications of suspended matter and chlorophyll-based satellite data products in coastal waters. In addition to algorithm work and image processing BEL-COLOUR will participate in sea borne cruises for the purposes of calibration of algorithms and for validation of the end products. The project "BEL-COLOUR", funded by the <a href="http://www.belspo.be">Federal Science Policy</a>, within the programme for Earth Observation "STEREO" - Study and management of Coastal Regions.