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: 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: The ability of any satellite gravity mission concept to monitor mass transport processes in the Earth system is typically tested well ahead of its implementation by means of various simulation studies. Those studies often extend from the simulation of realistic orbits and instrumental data all the way down to the retrieval of global gravity field solution time-series. Basic requirement for all these simulations are realistic representations of the spatio-temporal mass variability in the different sub-systems of the Earth, as a source model for the orbit computations. For such simulations, a suitable source model is required to represent (i) high-frequency (i.e., subdaily to weekly) mass variability in the atmosphere and oceans, in order to realistically include the effects of temporal aliasing due to non-tidal high-frequency mass variability into the retrieved gravity fields. In parallel, (ii) low-frequency (i.e., monthly to interannual) variability needs to be modelled with realistic amplitudes, particularly at small spatial scales, in order to assess to what extent a new mission concept might provide further insight into physical processes currently not observable. The new source model documented here attempts to fulfil both requirements: Based on ECMWF’s recent atmospheric reanalysis ERA-Interim and corresponding simulations from numerical models of the other Earth system components, it offers spherical harmonic coefficients of the time-variable global gravity field due to mass variability in atmosphere, oceans, the terrestrial hydrosphere including the ice-sheets and glaciers, as well as the solid Earth. Simulated features range from sub-daily to multiyear periods with a spatial resolution of spherical harmonics degree and order 180 over a period of 12 years. In addition to the source model, a de-aliasing model for atmospheric and oceanic high-frequency variability with augmented systematic and random noise is required for a realistic simulation of the gravity field retrieval process, whose necessary error characteristics are discussed. The documentation of the updated ESA Earth System Model (updated ESM) for gravity mission simulation studies is organized as follows: The characteristics of the updated ESM along with some basic validation is presented in Volume 1. A detailed comparison to the original ESA ESM (Gruber et al., 2011) is provided in Volume 2, while Volume 3 contains the description of a strategy to derive realistic errors for the de-aliasing model of high-frequency mass variability in atmosphere and ocean.

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

Description: This publication is a result of the 12th TRACE conference (Tree Rings in Archaeology, Climatology and Ecology) organized by the Department of Agriculture, Forests, Nature and Energy (DAFNE) of the Università della Tuscia (Viterbo, Italy) on May 08th – 11th 2013 in Viterbo, Italy. [...] A total of 20 manuscripts were submitted. After review 19 short papers are published in this volume, giving an overview of the wide spectrum of fields in tree-ring research.

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: Mit dem Journal „System Erde“ berichtet das Deutsche GeoForschungsZentrum GFZ über die unterschiedlichen Facetten seiner Forschungsarbeiten. Die Reihe richtet sich vor allem an Entscheidungsträger in Wissenschaft, Gesellschaft und Politik, an interessierte Wissenschaftlerinnen und Wissenschaftler sowie an die fachinteressierte Öffentlichkeit.