Description: Public fear for environmental and health impacts or potential leakage of CO2 from geological reservoirs is among the reasons why over the past decade CCS has not yet been deployed on a large enough scale so as to meaningfully contribute to mitigate climate change. Storage of CO2 under the seabed moves this climate mitigation option away from inhabited areas and could thereby take away some of the opposition towards this technology. Given that in the event of CO2 leakage for sub-seabed CCS the ocean would function as buffer for receiving this greenhouse gas, rather than the atmosphere, offshore CCS could particularly address concerns over the climatic impacts of CO2 seepage. In this paper we point out that recent geological studies confirm that leakage for individual offshore CCS operations may be highly unlikely from a technical point of view, if storage sites are well chosen, well managed and well monitored. But we argue that on a global long-term scale, for an ensemble of thousands or millions of storage sites, leakage of CO2 could take place in certain cases and/or countries for e.g. economic, institutional, legal or safety cultural reasons. We investigated what the impact could be in terms of temperature increase and ocean acidification if leakage would nevertheless occur, and addressed the question what the relative roles could be of on- and offshore CCS if mankind desires to divert the atmospheric damages resulting from climate change. For this purpose, we constructed a top-down energy-environment-economy model, with which we performed a probabilistic cost-benefit analysis of climate change mitigation with on- and offshore CCS as specific CO2 abatement options. One of our main conclusions is that even if there is non-zero leakage for CCS activity on a global scale, there is high probability that both onshore and offshore CCS could – on economic grounds – still account for anywhere between 20% and 80% of all future CO2 abatement efforts under a broad range of CCS cost assumptions.

Description: Abstract Legal requirement in Europe asks for Ecosystem-Based Fisheries Management (EBFM) in European seas, including considerations of trophic interactions and minimization of negative impacts of fishing on food webs and ecosystem functioning. Focusing on the interaction between fisheries and ecosystem components, the trophic model presented here shows for the first time the “big picture” of the western Baltic Sea (WBS) food web by quantifying structure and flows between all trophic elements and the impact of fisheries that were and are active in the area, based on best available recent data. Model results show that fishing pressures exerted on the WBS since the early nineties of the past century forces not only top predators such as harbour porpoises and seals but also cod and other demersal fish to heavily compete for fish as food and to cover their dietary needs by shifting to organisms lower in the trophic web, mainly to benthic macrofauna and / or search for suitable prey in adjacent ecosystems such as Kattegat, Skagerrak, central Baltic Sea and North Sea. While common sense implementations of EBFM have been proposed, such as fishing all stocks below Fmsy and reducing fishing pressure even further for forage fish such as herring and sprat, few studies compared such fishing to alternative scenarios. Different options for EBFM, with regards to recovery of depleted stocks and sustainable future catches, are presented here based on the WBS ecosystem model, the legal framework given by the new Common Fisheries Policy (CFP) and the Marine Strategy Framework Directive (MSFD) of the European Union. The model explores four legally valid future fishery scenarios: 1) business as usual, 2) maximum sustainable fishing (F = Fmsy), 3) half of Fmsy, and 4) EBFM with F = 0.5 Fmsy for forage fish and F = 0.8 Fmsy for other fish. In addition, a “No-fishing” scenario demonstrates, that neither individual stocks nor the whole system would collapse when all fishing activities from 2017 on would cease. Simulations show that “Business as usual” would perpetuate low 2016 catches from depleted stocks in an unstable ecosystem where endangered species may be lost. In contrast, an “EBFM” scenario - with herring and sprat fished at 0.5 Fmsy level and cod and other stocks fished at 0.8 Fmsy level - allows the recovery of all stocks with strongly increased catches close to the maximum (at Fmsy) for cod and flatfish and catches similar to the 2016 level for herring and sprat but with strongly reduced fishing effort. Model and methodology presented here are considered suitable to assess MSFD Criterion D4C2 in the WBS.

Description: Summary The Bathymetrists Seamounts (BSM) are located north of the volcanic Sierra Leone Rise in the eastern Atlantic between 6° and 9°N. The three W-E, N-S and NE-SW striking directions of the seamounts indicate a clear structural control for the emplacement of these volcanoes. The origin of the melts, their relationship to the Sierra Leone Rise and the role of the faults in the formation of the melts are unknown as the BSM could be explained by plume related volcanism or decompression melting beneath deep (transform) faults. The SEDIS-cruise M152/2 of RV METEOR strove for a better understanding of the life cycle of submarine volcanoes and their effect on the oceanic lithosphere in the oceanic intraplate setting of the BSM and the relationship to the Sierra Leone Rise. The aims were: 1) to understand the interaction between crustal thickness, tectonics and volcanic phases, 2) to investigate the structural, chronological and petrological evolution of individual seamounts and seamount chains, 3) to review slope failures and resulting mass flow processes. We addressed these objectives by more than 4000 km highresolution reflection seismic and more than 5000 km of parametric echosounder, multi-beam, and gravity and magnetic profiles. Rock samples for ground truthing and geochemical research have been collected during 14 dredge stations. We further determined the concentrations in surface seawater and air and the state of air-sea exchange of a number of nowadays globally banned pesticides, polychlorinated biphenyls, brominated flame retardants, polycyclic aromatic hydrocarbons and their derivatives. Zusammenfassung Die Bathymetrists Seeberge liegen nördlich der Sierra Leone Schwelle, einer vulkanischen Plattform im östlichen Atlantik zwischen 6° und 9° N. Diese submarinen Vulkane gruppieren sich entlang W-E, N-S und NE-SW Trends, was eine strukturelle Kontrolle der Vulkanentstehung indiziert. Die Schmelzentstehung sind unbekannt und können mit PlumeVulkanismus oder Dekompressionsschmelzen unter bisher nicht untersuchten Störungen und tiefen Transformstörungen zusammenhängen. Der Bezug zur Sierra Leone Schwelle ist ebenfalls unbekannt. Im Zuge der SEDIS-Expedition M152/2 mit FS METEOR wurde der Lebenszyklus von Unterwasservulkanen und deren geochemischen Einfluss auf die ozeanische Lithosphäre der Bathymetrists Seeberge untersucht. Anhand der profilhaften geophysikalischer Messungen und Dredge-Proben wollen wir 1) die Wechselwirkung zwischen Krustenmächtigkeit, Tektonik und Vulkanismus verstehen, 2) die strukturelle, chronologische und petrologische Entwicklung von Vulkanen und Vulkanketten untersuchen, und 3) Auslösemechanismen, Transportprozesse und Volumina von Hangrutschungen studieren. Zur Bearbeitung der wissenschaftlichen Fragen sammelten wir mehr als 4000 km mehrkanal-reflexionsseismischer und mehr als 5000 km parametrische Sedimentecholot, Fächerlot, Schwere und Magnetik-Profile. Für die geochemischen Arbeiten sammelten wir an 14 Stationen Gesteinsproben unter Einsatz einer Dredge. Die regelmäßige Beprobung der Luft und des Oberflächenwassers diente der Bestimmung der Konzentration von heute weltweit verbotenen Pestiziden, polychlorierten Biphenylen, bromierten Flammschutzmitteln, polyzyklischen aromatischen Kohlenwasserstoffen und deren Derivaten und um den Austausch zwischen Luft und Meer weiter zu verstehen.

Description: Report on the current observing status in the North Atlantic subpolar gyre and the South Atlantic subtropical gyre, containing the results of the investigation on regional observing activities, systems, and connectivity in relation to climate and ecosystems

Description: Rio Grande Rise: microcontinent, mantle plume, or both? The origin of the Rio Grande Rise (RGR) is debated. It could represent a continental sliver, or a large igneous province that was emplaced in the late Cretaceous after the opening of the South Atlantic Ocean. The interplay between the RGR and the nearby Jean Charcot Seamount Chain (JCSC) is also not understood. Cruise MSM82 dredge sampled rocks from the JCSC and the RGR and measured two seismic refraction profiles across the RGR where it is bisected by a long rift graben. A range of geophysical data were also collected during much of the expedition, including magnetics, gravity, bathymetry (Kongsberg EM 122), sub-bottom profiling (ATLAS PARASOUND DS P70) and ADCP data. The combination of geochronological, geochemical and geophysical information will provide a unique window on the relation between mantle plumes, continental fragments and the evolution of large igneous provinces.

Description: Assessment of the observing system fitness for storm surge forecasting and warning in the Atlantic

Description: Prior to the 4th annual AtlantOS meeting in month 48 a project progress report for the external project boards (EB and ISTAB) will be prepared to enable them to be as good as possible prepared for the meeting and to ensure consequently that AtlantOS receives as constructive as possible recommendations from the boards. This report, together with the two external summary board meeting reports, which will be requested from the EB and ISTAB, will represent D11.7.

Description: Species richness and abundance are two commonly measured parameters used to characterize invasion risk associated with transport vectors, especially those capable of transferring large species assemblages. Understanding the relationship between these two variables can further improve our ability to predict future invasions by identifying conditions where high-risk (i.e. species-rich or high abundance or both) and low-risk (i.e. species-poor and low abundance) introduction events are expected. While ballast water is one of the best characterized transport vectors of aquatic non-indigenous species, very few studies have assessed its magnitude at high latitudes. We assessed the arrival potential of zooplankton via ballast water in the Canadian Arctic by examining species richness, total abundance, and the relationship between the two parameters for zooplankton in ships from Europe destined for the Arctic, in comparison with the same parameters for ships bound for Atlantic Canada and the Great Lakes. In addition, we examined whether species richness and/or total abundance were influenced by temperature change and/or ballast water age for each shipping route. We found that species richness and total abundance for Arctic and Great Lakes ships were significantly lower than those for Atlantic ships. Differences in species richness and total abundance for ships utilizing different shipping routes were mostly related to ballast water age. A significant species richness–total abundance relationship for Arctic and Great Lakes ships suggests that these parameters decreased proportionately as ballast water aged. In contrast, the absence of such a relationship for Atlantic ships suggests that decreases in total abundance were accompanied by little to no reduction in species richness. Collectively, our results indicate that the arrival potential of zooplankton in ballast water of Arctic ships may be lower than or similar to that of Atlantic and Great Lakes ships, respectively.