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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 RRS Discovery cruise 304 was conducted from 12 May to 6 June 2005 from and to Santa Cruz (Tenerife). The cruise was completed as part of the NERC founded RAPID programme to monitor the meridional overturning circulation at 26 N. The primary purpose was to service the eastern boundary and Mid-Atlantic Ridge part of the 26 N mooring array which had previously been serviced during the RRS Charles Darwin cruises 170 and 177. 12 moorings were successfully recovered, however two of the shallow eastern boundary moorings failed to release. Intense fishing activity at these sites is likely to be the cause. 12 mooring and four bottom pressure landers were re-deployed. Data from two bottom mounted inverted echosounders was uploaded via acoustic telemetry. A total of 10 CTD casts to calibrate the mooring sensors were carried out and 3 Argo floats (from the UK Met Office) were launched. The moored sensors are CTD loggers for the most part but also bottom pressure sensors, different types of current meters and inverted echosounders are used to determine the strength and structure of the meridional overturning circulation.

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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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    This equipment trials cruise has provided opportunities for test and verification of technology under development at the Proudman Oceanographic Laboratory (POL), the Scottish Association for Marine Science (SAMS) and the National Oceanography Centre, Southampton (NOC,S). This includes equipment developed during the first year of funding under OCEANS 2025 (theme 8). Testing technology in the ocean environment is invaluable in assessing fitness for purpose. Specifically, the cruise tested: A Spar wave buoy (NOC,S) biogeochemical sensors (NOC,S); an UAV system (NOC,S); a video grab system "HyBis" (NOC,S), A benthic Multicore (NOC,S), A benthic lander and associated torroidal Telemetry buoy (POL), and a shallow tow towfish (POL). Testing in Spanish waters (near Tenerife, Gran Canaria and Fuerteventura) has been invaluable. The time on passage has been minimised (the transition from deep to shallow water is less than a days steaming) and the calm conditions to the southwest of the islands in the consistent prevailing north easterly winds have enabled deployment and recovery techniques to be tried and optimised in safety.

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    This project was a hydrographic section at latitude 24°N, with physical, chemical and biological measurements. The section was a complete section from continent to continent from North America (Caribbean) to Africa (off the coast of the Western Sahara). The section started and ended in 200 metres water depth, at the edge of the continental shelf. This was a contribution to the international CLIVAR/Carbon repeat hydrography program (http://ioc3.unesco.org/ioccp/Hydrography/New_GlobalMap.html). Climate change will be studied by comparing the new data with historical measurements. Ocean heat transport plays a major role in the coupled ocean-atmosphere climate system. We will study the present-day circulation by calculating the heat and freshwater transported by the ocean across the 24°N latitude. The ocean western boundary current system, in this case the Gulf Stream flowing through the Florida Strait, plays a crucial role in the oceanic heat transport. Therefore a crossing of the Florida Strait will be carried out to establish the status of this important ocean feature. All data arising from the cruise will be lodged and made available via the British Oceanographic Data Centre (BODC), UK.

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    The objective of cruise JC103 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. During passage from port of Spain to Nassau trial CTDs were completed in the waters of the Turks and Caicos Islands. After departing Nassau on 29th April work commenced on the western boundary sub-array comprising of moorings WBADCP, WBAL, WB1, WB2, WB2l, WB2h, WB4 and WB4L. The ship returned to Nassau on 6th May to disembark one person before sailing east once again. The final mooring of the wester sub-array was serviced on 8th May before continuing east to the mid-Atlantic Ridge (MAR) sub-array. Work on the MAR sub-array commenced on 13th May at mooring MAR0. The other moorings in this sub-array were MAR1, MAR1L, MAR2, MAR3 and MAR3L were all completed by 18th May. On the following day the NOG mooring was deployed and as the ship transited to the astern sub-array the first of 5 Argo floats was deployed on 21st May. The eastern boundary sub-array starts at EB1, which was serviced on 23rd May. Following this moorings at EB1L, EBHi, EBH1, EBH2, EBh3,EBh4 and EBH4L in the following days up until 31st May. A number of CTDs were completed form 31st may to 2nd June.

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    The goal of this cruise was to recover and redeploy some RAPID-MOC moorings near the Eastern Boundary as part of our six-month turnaround programme. Specific cruise objectives were to: 1. Recover moorings EB1 (24 microcats) and EB2 (MMP profiling from 50m to 2500m with microcats and current meters below), two principal tall eastern boundary moorings, sited on a Topex crossover point near 24N, 24W. 2. Redeploy EB1 (24 inductive microcats plus the telemetry system) and EB2 (MMP mooring). 3. Deploy EBADCP to replace the instrument deployed in April but trawled after 10days and recovered by the R/V Poseidon. 4. Deploy two URI Pressure Inverted Echo Sounders. One deployed in 1000m and one in 5000m next to the BPR lander at mooring EB1. 5. CTD stations for pre and post deployment calibrations of all mooring instrumentation. 6. Search for and if possible recover MMP mooring EB2 deployed in April 2004 and located 100km north south of Gomorra in October 2004.

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    Cruise D344 was primarily used for the annual servicing of the eastern boundary and mid-Atlantic ridge moorings that form part of the RAPID-MOC mooring array across the North Atlantic at 26°N. In addition, the easternmost western boundary mooring, WB6, was serviced and the trial current meter mooring off the island of Abaco, WB-CM, was recovered. As the Discovery had made a faster passage than anticipated, a number of CTD stations were performed along 24° 30'N to augment the hydrography section scheduled to take place in January 2010. The instruments deployed on the RAPID-MOC array consist of bottom pressure recorders, CTD loggers, and current meters which, combined with time series measurements of the Florida Channel Current, and wind stress estimates, will be used to determine the strength and structure of the MOC at 26.5°N.

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    There were five main objectives for the trials cruise: The first tests of the Autosub Long Range AUV, testing of the HyBIS video guided grab system, testing of the MYRTLE-X Lander systems, testing of a deep camera system for the Lake Ellsworth probe and test deployments of the PELAGRA neutrally buoyant sediment capture drifters. The working area was about 300 miles south west of the Canary Islands, in international waters, over benthic plains of 4000 m depth, with some tests of the video systems over a isolated sea mount rising to 1200 m depth. Most of the objectives of the cruise where met, with successful diving and control of the Autosub LR, tests of the HyBIS and Ellsworth camera systems, and 3 test deployments and recoveries of two PELAGRA floats. Several wire tests of MYRTLE-X systems were carried out, predominantly successful, but concerns over the release system prevented a deployment of the lander. The tests were all purely engineering, hence no science data were collected.

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    The cruise is a component of RAPID-WATCH, whose objectives are: to deliver a decade-long time series of calibrated and quality-controlled measurements of the Atlantic MOC from the RAPID-WATCH array and; to exploit the data from the RAPID-WATCH array and elsewhere to determine and interpret recent changes in the Atlantic MOC, assess the risk of rapid climate change, and investigate the potential for predictions of the MOC and its impacts on climate. Objectives of this cruise: to recover, calibrate and redeploy moorings from the eastern boundary and mid-Atlantic ridge subarrays of the 26.5N line of RAPID moorings.