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Eastern Boundary Upwelling Ecosystems (EBUEs) are associated with high biological productivity, high fish catch and they highly contribute to marine carbon sequestration. Whether coastal upwelling has intensified or weakened under climate change in the past decades is controversially discussed and different approaches (e.g., time-series of chlorophyll, wind, sea surface temperature, modeling experiments) have been considered. We present a record of almost two decades of particle fluxes (1991–2009) from ca. 600 to 3100 m water depth in the Canary Basin at site ESTOC (European Station for Time series in the Ocean Canary Islands; ca. 29°N, 15°30.W, ca. 3600 m water depth), located in the offshore transition zone of the northern Canary Current-EBUE. We compare these flux records with those measured at a mesotrophic sediment trap site further south off Cape Blanc (Mauritania, ca. 21°N). The deep ocean fluxes at ESTOC in ca. 3 km recorded the evolution of the coastal Cape Ghir filament (30–32°N, 10–12°W) due to lateral advection of particles, whereas the upper water column sediment traps in ca. 1 km reflected the oligotrophic conditions in the overlying waters of ESTOC. We observed an increased emphasis in spring-time fluxes since 2005, associated with a change in particle composition, while satellite chlorophyll biomass did not show this pattern. Due to its northern location in the CC-EBUEs, spring biogenic fluxes at ESTOC provide a better relationship to the forcing of the North Atlantic Oscillation than those recorded further south off Cape Blanc. Off Cape Blanc, deep fluxes showed the best overlap with the deep ESTOC fluxes during the spring season before 2005. On the long-term, both chlorophyll and particle fluxes showed an increasing trend at ESTOC which was not observed further south at the mesotrophic Cape Blanc site. This might indicate that, depending on their location along the NW African margin, coastal upwelling systems react differently to global change.

SONNE-Berichte

The hydrothermally active Menez Gwen seamount at 37��N on the Mid-Atlantic Ridge was selected as a key study site for interdisciplinary geological, chemical, and biological studies within the Research Area "Geosphere - Biosphere Interactions" of the MARUM Cluster of Excellence. The goal of cruise M 82/3 was to gain a better understanding of the hydrothermal processes at this neovolcanic system by closely integrating geochemical and biological investigations, using state of the art in situ technology together with interdisciplinary analyses on board and in the home laboratories. The key research goals of the cruise were achieved thanks to a total of 21 successful ROV dives that were used for video mosaicking of hydrothermal vent habitats, detailed measurements of physico-chemical environmental parameters with in situ instruments, coordinated microhabitat-specific collection of hot and diffuse vent fluids, biota and geological sample collection, deployment of in situ experiments, and the recovery of experiments that had been deployed during a R/V POSEIDON cruise in July 2010. A further achievement of the cruise was the discovery of new hydrothermal vent field. Hydrothermal activity was detected by combining gas bubble detection using R/V METEOR's new EM 122 multibeam echosounder with analyses of water column samples and in situ sensor data. This method allowed us to confirm hydrothermal activity at a new site named Bubbylon with the ROV and provided data indicating the presence of several other sites with hydrothermal activity in the Menez Gwen area., METEOR-Berichte

Cruise leg MSM 29 investigated the consequences climate changes and the decline in sea ice has on Arctic ecosystems, which is one of the most important challenges for Earth Sciences. Rapidly changing physical and chemical conditions, as observed and projected for the future, will affect the ecosystem functioning including productivity, remineralisation, and energy flow between ecosystem compartments. The cruise had two main working areas: the deep-sea long-term observatory HAUSGARTEN in the eastern Fram Strait, and the long-term Kongsfjord transect (3 sites on the continental shelf off Svalbard). HAUSGARTEN observatory includes 17 permanent sampling sites along a depth transect (1,000 - 5,500 m) and along a latitudinal transect following the 2,500 m isobath. Unfortunately it was not possible to reach all observatory sites due to the present sea ice cover in the region during the duration of our cruise. Sediment from TV-guided MUC sampling will be analysed to estimate the input of food/energy to the seafloor, benthic activities, and the total biomass of the smallest sediment-inhabiting organisms. Water samples from CTD/rosette casts are used to investigate biogeochemical parameters as well as phytoplankton and bacteria communities in surface layers. AUV dives at the ice edge were used to obtain high-resolution biogeochemical profiles in the water column. Targeted measurements and sampling at the seafloor and in the water column as well as the installation of bioturbation experiments were achieved by several ROV dives. The cruise added to the long-term ecosystem time-series study at the deep-sea observatory HAUSGARTEN and contributed to the HGF-Research-Program PACES, the ERC project Abyss and the BMBF project TRANSDRIFT., MARIA S. MERIAN-Berichte

The cruise leg MSM13/3 investigated chemosynthetic ecosystems of the deep Eastern Mediterranean. At fluid escape structures in water depths of 1000- 2000 m energy rich chemical substances such as sulphur and hydrocarbon compounds are available to fuel rich and abundant microbial life and diverse chemosynthetic ecosystems. The main objectives of leg MSM13/3 were 1) to obtain a quantitative insight in element cycling and export at different types of fluid seeps in the Eastern Mediterranean and 2) to understand the relation and interaction between fluid seepage and seep biodiversity and community distribution. Another special type of chemosynthetic ecosystem investigated during MSM 13/3 were large wood falls, which had been deployed 3 and 2 years ago, and which were now resampled to get a better understanding of temporal succession of wood degrading communities. The main technology used for these objectives were the ROV QUEST4000 (MARUM) with its diverse payloads operated by the MPI Bremen, allowing targeted, coupled videographic, biogeochemical and ecological investigations,as well as the online heat flux corer of IFM Geomar. We used these tools in a combination to quantify physical, biogeochemical and ecological processes in chemosynthetic ecosystems, and to study the link between the deep-water geosphere and biosphere in the Eastern Mediterranean. The expedition contributed to the ECs 7th FP HERMIONE, the GDRE DIWOOD and ESF EUROCORES project CHEMECO, as well as to the goals of the research centre MARUM (Geosphere- Biosphere Research)., MARIA S. MERIAN-Berichte

The aim of the cruise was to perform AUV and ROV pre-site surveys of potential drill sites which are planned to be drilled during a MeBo cruise in 2011 in the Black Sea. The selected locations represented deposits where shallow gas hydrates have already been sampled by gravity and piston coring and where gas emissions to the water column have been detected. For the first time we could acquire AUV bathymetric maps from five gas hydrate sites of the Black Sea in Ukrainian and Georgian waters. In the Sorokin Trough two mud volcanoes, the Dvurechenskii MV and the Helgoland MV were mapped by the AUV, which gave us very detailed information to plan and conduct ROV dives on the mud volcanoes. The maps allowed us to investigate mud pools for the first time in the center of Helgoland MV. Temperature measurements showed clearly higher temperatures in sediments of the Helgoland MV, in contrast to Dvurechenskii MV which showed a constant temperature of 16.5�� C between 10-30 mbsf. Since 16.5�� C marks the gas hydrate stability boundary the temperature is interpreted as a result of diverse gas hydrate dynamics (decomposition and formation of gas hydrates). Further site surveys have been performed at a new flare site in 1700 m water depth and at Kerch Flare which is a prominent gas emission site in the eastern Sorokin trough at 900 m water depth. Due to restrictions only one seep site in Georgian waters, the Colkheti oil seep on the western side of Kobuleti Ridge could be mapped in detail. The AUV surveys have been accompanied by ROV dives, which were used to quantify gas ebullition from the seabed, acoustic imaging of flares and bathymetric surveys of larger areas of gas hydrate presence., MARIA S. MERIAN-Berichte

R/V METEOR Cruise No. 61 was divided into three different legs, which all focused on the NEAtlantic to the west of Ireland from the Porcupine Seabight towards the Rockall Bank. Legs 1 and 3 concentrated on geo-biological studies on the carbonate mounds in this region, which are covered by a unique cold water coral fauna. Leg 2 dealt with seismic investigations in order to investigate the extension processes that led to the development of the Porcupine rift basin. The foci of the individual legs were on the following themes. M61-1 was a multidisciplinary cruise addressing biological, paleo-geological and hydrographical scientific objectives in the carbonate mound provinces west of Ireland in the eastern Porcupine Seabight and on the Rockall Bank. The cruise started in Lisbon (Portugal) and ended in Cork (Ireland). M61-1 activities were embedded within the ESF-DFG MOUNDFORCE project of the EUROMARGINS Programme. Together with the succeeding M61-3 cruise, these Meteor activities document Germany��s strong scientific and logistic support for the success of this challenging programme. Investigations are also designed as a preparatory cruise for the EUproject HERMES (Hotspot Ecosystem Research on the Margins of European Seas; start April 2005). All institutions participating in M61-1 are partners in HERMES Work package 2 "Coral Reef and Carbonate Mound Systems". M 61-2 was directed at researching the earth's crust in the vicinity of the Porcupine rift basin. During this leg, seismic research has been undertaken in the Porcupine Basin west of Ireland, an area that represents a natural laboratory for the investigation of extensional processes. Firstly, both sides of a rift basin occurring in close proximity to each other could have been studied here, allowing questions about the symmetry of extension to be addressed by several east-west profiles parallel to the direction of extension. Secondly, the amount of extension increases from north to south, so a series of east-west cross sections on different latitudes has provided information on crustal structure during variable extension. The spatial changes between these sections also represent the temporal development of the rift through continued extension. In order to achieve these research goals, a series of east-west oriented wide angle reflection profiles in the Porcupine Basin has been acquired. These profiles aid in the explanation of extensional processes and their development through continued extension. They also address insufficiently explained questions about the initiation of large scale magmatism and intrusion, the onset of mantle serpentinisation and the development of detachment faults. M61-3 During this leg, the only recently discovered 'carbonate mounds' on the NWEuropean continental margin have been investigated, which represent unique geo- and ecosystems for European waters. The broad scientific interest that is directed at these mounds is reflected in three EU-projects, which until recently almost exclusively concentrated their efforts on the mounds, as well as the currently operating ESF-EUROMARGINS project MOUNDFORCE M 61-3 focused on the use of a 'Remotely Operated Vehicle' (ROV) for the investigation of the carbonate mounds. The primary tasks of Bremen's QUEST ROV were a detailed characterization of individual mound structures, selective sample collection and the retrieval of sensor systems placed at the seafloor one year before. These ROV tasks have been supplemented by hydro-acoustic measurements and conventional sediment sampling in order to work - in close collaboration with M61-1 - on the main research focuses of the MOUNDFORCE project: (a) analysis of the environmental factors that drive the development of the 'carbonate mounds', (b) surveying the benthic communities in dependence of changing environmental factors and (c) investigations to the stabilization and lithification of the mound sediments., METEOR-Berichte

METEOR-Berichte

R/V METEOR Cruise No. 61 was divided into three different legs, which all focused on the NEAtlantic to the west of Ireland from the Porcupine Seabight towards the Rockall Bank. Legs 1 and 3 concentrated on geo-biological studies on the carbonate mounds in this region, which are covered by a unique cold water coral fauna. Leg 2 dealt with seismic investigations in order to investigate the extension processes that led to the development of the Porcupine rift basin. The foci of the individual legs were on the following themes. M61-1 was a multidisciplinary cruise addressing biological, paleo-geological and hydrographical scientific objectives in the carbonate mound provinces west of Ireland in the eastern Porcupine Seabight and on the Rockall Bank. The cruise started in Lisbon (Portugal) and ended in Cork (Ireland). M61-1 activities were embedded within the ESF-DFG MOUNDFORCE project of the EUROMARGINS Programme. Together with the succeeding M61-3 cruise, these Meteor activities document Germany´s strong scientific and logistic support for the success of this challenging programme. Investigations are also designed as a preparatory cruise for the EUproject HERMES (Hotspot Ecosystem Research on the Margins of European Seas; start April 2005). All institutions participating in M61-1 are partners in HERMES Work package 2 "Coral Reef and Carbonate Mound Systems". M 61-2 was directed at researching the earth's crust in the vicinity of the Porcupine rift basin. During this leg, seismic research has been undertaken in the Porcupine Basin west of Ireland, an area that represents a natural laboratory for the investigation of extensional processes. Firstly, both sides of a rift basin occurring in close proximity to each other could have been studied here, allowing questions about the symmetry of extension to be addressed by several east-west profiles parallel to the direction of extension. Secondly, the amount of extension increases from north to south, so a series of east-west cross sections on different latitudes has provided information on crustal structure during variable extension. The spatial changes between these sections also represent the temporal development of the rift through continued extension. In order to achieve these research goals, a series of east-west oriented wide angle reflection profiles in the Porcupine Basin has been acquired. These profiles aid in the explanation of extensional processes and their development through continued extension. They also address insufficiently explained questions about the initiation of large scale magmatism and intrusion, the onset of mantle serpentinisation and the development of detachment faults. M61-3 During this leg, the only recently discovered 'carbonate mounds' on the NWEuropean continental margin have been investigated, which represent unique geo- and ecosystems for European waters. The broad scientific interest that is directed at these mounds is reflected in three EU-projects, which until recently almost exclusively concentrated their efforts on the mounds, as well as the currently operating ESF-EUROMARGINS project MOUNDFORCE M 61-3 focused on the use of a 'Remotely Operated Vehicle' (ROV) for the investigation of the carbonate mounds. The primary tasks of Bremen's QUEST ROV were a detailed characterization of individual mound structures, selective sample collection and the retrieval of sensor systems placed at the seafloor one year before. These ROV tasks have been supplemented by hydro-acoustic measurements and conventional sediment sampling in order to work - in close collaboration with M61-1 - on the main research focuses of the MOUNDFORCE project: (a) analysis of the environmental factors that drive the development of the 'carbonate mounds', (b) surveying the benthic communities in dependence of changing environmental factors and (c) investigations to the stabilization and lithification of the mound sediments.

METEOR-Berichte

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