Description: Numerous potentially toxic plankton species commonly occur in the Black Sea, and phycotoxins have been reported. However, the taxonomy, phycotoxin profiles, and distribution of harmful microalgae in the basin are still understudied. An integrated microscopic (light microscopy) and molecular (18S rRNA gene metabarcoding and qPCR) approach complemented with toxin analysis was applied at 41 stations in the northwestern part of the Black Sea for better taxonomic coverage and toxin profiling in natural populations. The combined dataset included 20 potentially toxic species, some of which (Dinophysis acuminata, Dinophysis acuta, Gonyaulax spinifera, and Karlodinium veneficum) were detected in over 95% of the stations. In parallel, pectenotoxins (PTX-2 as a major toxin) were registered in all samples, and yessotoxins were present at most of the sampling points. PTX-1 and PTX-13, as well as some YTX variants, were recorded for the first time in the basin. A positive correlation was found between the cell abundance of Dinophysis acuta and pectenotoxins, and between Lingulodinium polyedra and Protoceratium reticulatum and yessotoxins. Toxic microalgae and toxin variant abundance and spatial distribution was associated with environmental parameters. Despite the low levels of the identified phycotoxins and their low oral toxicity, chronic toxic exposure could represent an ecosystem and human health hazard.

Description: This task set out to increase communication between the ocean monitoring and modelling communities in the Baltic Sea area. Through these improved communications, the goal was to advance and improve the HELCOM marine environmental assessments. To gain confidence in the numerical model outputs, an effort was undertaken to ensure ocean observing in-situ data, collected by multiple nations in the Baltic Sea, was assimilated into a numerical model. Here, we report on the development of indicators, as requested by our stakeholders, and we discuss if the Baltic Sea numerical modelling efforts are ready to augment regional environmental status reports, and can our results help guide environmental management in the region.

Description: Net-zero climate policies foresee deployment of atmospheric carbon dioxide removal wit geological, terrestrial, or marine carbon storage. While terrestrial and geological storage would be governed under the framework of national property rights, marine storage implies that carbon is transferred from one global common, the atmosphere, to another global common, the ocean, in particular if storage exceeds beyond coastal applications. This paper investigates the option of carbon dioxide removal (CDR) and storage in different (marine) reservoir types in an analytic climate-economy model, and derives implications for optimal mitigation efforts and CDR deployment. We show that the introduction of CDR lowers net energy input and net emissions over the entire time path. Furthermore, CDR affects the Social Cost of Carbon (SCC) via changes in total economic output but leaves the analytic structure of the SCC unchanged. In the first years after CDR becomes available the SCC is lower and in later years it is higher compared to a standard climate-economy model. Carbon dioxide emissions are first higher and then lower relative to a world without CDR. The paper provides the basis for the analysis of decentralized and potentially non-cooperative CDR policies.

Description: Identification of local and regional impacts of oxygen, heat and pH related “Extreme Marine Events”: Ocean model data products are overlaid with existing marine biological datasets to identify sensitive areas and organism vulnerabilities.

Description: Report on ASV-Network structure and roadmap

Description: This study uses an existing perturbed parameter ensemble (PPE) of simulated ocean CO2 removal (CDR) to better determine sustainable pathways of ocean-based NET deployment and to provide information to constrain the design of subsequent modelling experiments. The results show that ocean alkalinity enhancement (OAE) can only help meet SDG13 (Climate Action) when other ambitious mitigation efforts are taken. This reinforces that OAE is not a substitute for emissions reduction, but could contribute to meeting our climate goals (if other factors suggest OAE is worth doing). For SDG14 (Life Below Water), the results suggest OEA can contribute to limiting or even reversing ocean acidification. Meeting many other SDG14 objectives is closely linked to also meeting SDG13. A key recommendation is therefore, that subsequent simulations in OceanNETs should only use SDG13 compatible baseline scenarios, unless there is some specific need for process understanding at higher levels of climate change. The analysis has also determined that the idealized CDR in the PPE is not suitable for determining many socio-economic constraints and the implications that these have for meeting the SDGs. Another key recommendation is therefore, that subsequent simulations within OceanNETs should use more realistic scenarios of CDR deployment.

Description: This study sets out to assess the economic value of ocean observations in qualitative terms. The study aims to examine the perspective of selected co-developers and end users on the impact of the EuroSea Key Exploitable Results on them. While efforts were made to collect quantitative data on the economic impact of the results on the users, this report uses a focussed case study approach to qualitatively assess the value of the demonstration products and services for the co-developers and users. The report focusses on the main demonstration products and services with potential for commercialisation in EuroSea that were identified in the exploitation strategy.

Description: This document demonstrates the capability of seasonal forecasting systems to predict observable and user-relevant ocean climate indicators.

Description: Research undertaken in Task 2.2 identified a range of governance challenges to ocean-based NETs related to the global ocean governance framework, e.g., linked to the transboundary nature of the ocean, potential effects of ocean-based NETs on the ocean’s condition and marine ecosystem services, as well as the many unknowns and uncertainties linked to NET-deployment. The fragmented approaches and frameworks in place to govern the global ocean further complicate comprehensive governance of these emerging technologies. This deliverable presents results from a workshop that explored how oceanbased NETs should be governed to best confront these challenges and integrate international climate targets as well as global goals for ocean and biodiversity conservation, in addition to global ambitions towards sustainable development. The workshop is part of research undertaken by Task 2.2 to assess how ocean-based NETs are addressed by the current global ocean governance framework and develop governance scenarios and recommendations to policy makers for a “good governance” of NETs in the ocean.

Description: Report on assessment of the EuroSea observational (and thematic) networks coordination This Deliverable serves to present the initial situation, in terms of coordination, of the observation and thematic networks in EuroSea represented in work package 3 (WP3). The networks include the networks represented in EuroGOOS and additional ones. The study is based on a comprehensive questionnaire that was answered by all EuroSea WP3 tasks. In addition, information from the Global Observing Networks of GOOS was considered. An important basis for the questionnaire was the list of "Network Attributes, Commitment and Benefits -What it means to be an OPA network" which was compiled by the Observation coordination group (OCG) of GOOS. This deliverable is linked to the deliverable D3.10 that will repeat the assessment at the end of the EuroSea project to assess the evolution of the coordination over the period of the EuroSea project. The present study shows that the observation and thematic networks in EuroSea all have highly developed coordination mechanism elements, except for task 3.7 - ASV, which represents a new network to be established. Given the spectrum of coordination themes and envisioned targets significant heterogeneity across the networks is also evident. The coordination of ship-based observations is not fully represented in EuroSea (and thus in EuroGOOS) and ideally this task should have been divided into research vessels and commercial vessels (container ships, ferries) but as it stands currently is dominated by one technology only (Ferrybox). This reflects the situation in EuroGOOS. For the thematic networks it is interesting to note that the observatories that are operated in task 3.8 (Augmented observatories) are not represented in the observational networks (task 3.1-3.7). The assessment presented in this deliverable has its focus on the status quo. It does not question or analyze the necessity for individuals, institutions and countries to be represented in a network - “Why should individuals, institutions or countries feel a need or a motivation to engage with the networks?”. It seems logical that networks are only founded, maintained and developed when individuals see an advantage in their involvement in a network – for themselves, their institution or a country. The "characteristics" of the apparent advantage of contributing to a network is likely of central importance. For example, if the advantage is only that there are no disadvantages (e.g. fines), a further development and improvement of the network is questionable. This important investigation of the motivation of individuals will be part of final assessment prepared in D3.10.