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.

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.

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).

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).

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.

These mooring operations were completed as a part of the United Kingdom Natural Environment Research Council (NERC) funded RAPID Programme to monitor the Atlantic Meridional Overturning Circulation at 26.5°N. The primary purpose of this cruise was to service the Eastern Boundary and Mid-Atlantic Ridge sections of the 26.5°N mooring array first deployed during RRS Discovery cruises D277 and D278 (SOC cruise report number 53), and serviced in 2005 during RRS Charles Darwin cruise CD177 (NOCS cruise report number 5), in 2006 on RRS Discovery cruise D304 (NOCS cruise report number 16) and FS Poseidon cruises P343 and P345 (NOCS cruise report number 28) and in 2007 on RRS Discovery cruise D324 (NOCS cruise report number 34). Cruise D334 started and finished in Tenerife, Spain and covered the Eastern Boundary and Mid-Atlantic Ridge moorings deployed on D324 and P343. This cruise was the fourth annual refurbishment of the Eastern Boundary and Mid-Atlantic Ridge sections of the mooring array. The array will be further refined and refurbished during subsequent years. The instruments deployed consist of a variety of current meters, bottom pressure recorders, CTD loggers and Inverted Echosounders, which, combined with time series measurements of the Florida Straits current and wind stress estimates, will be used to determine the strength and structure of the MOC at 26.5°N.

This cruise is part of the UK science contribution to the international SOLAS project (Surface Ocean Lower Atmosphere Study www.uea.ac.uk/env/solas/) which aims to advance our understanding of environmentally important interactions between the ocean and the atmosphere. Data collected during the cruise will help to determine the influence of coastal/shelf regions (20-200 km offshore) on microbiological activity in the ocean and chemical interactions between the ocean and the atmosphere. Deep water containing high concentrations of nutrients such as nitrate, and gases such as nitrous oxide and methane, rises to the surface (upwells) at the Mauritanian shelf edge and moves offshore. These nutrients can be chemically altered by sunlight and used by bacteria and microscopic plants to grow. The gases escape to the atmosphere and contribute to global warming. This cruise will sample the upwelled water as it moves offshore measuring its temperature, salinity, nutrient and gas content and the impact this water has on microbiological growth and atmospheric composition in order to improve international global climate models. The cruise has three scientific objectives: 1. To determine the role of upwelling on the supply, loss and air-sea exchange of climatically important gases produced by plankton 2. To determine the role of light in breaking down upwelled and recently produced dissolved organic matter and in producing climatically important trace gases 3. To determine the impact of nutrient enriched upwelled water on the spatial and temporal variability of plankton community structure and activity and resultant influence on biogenic gas flux

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.

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.

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.