Validation of MERIS bio-optical products with in situ data in the turbid Lithuanian Baltic Sea coastal waters

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Testing the Potential for Predictive Modeling and Mapping and Extending Its Use as a Tool for Evaluating Management Scenarios and Economic Valuation in the Baltic Sea (PREHAB)

Peer reviewe

Characterization of biomethanol–biodiesel–diesel blends as alternative fuel for marine applications

The ambitious new International Maritime Organization (IMO) strategy to reduce greenhouse gas emissions from ships will shape the future path towards the decarbonization of the fleet and will bring further ecological challenges. In order to replace the larger oil-based part of marine fuel with components from renewable sources, it is necessary to develop multi-component blends. In this work, biomethanol and biodiesel with two additives—dodecanol and 2-ethylhexyl nitrate—in 20 blends with marine diesel oil (MDO) were selected as alternative components to replace the pure marine diesel oil-based part of marine fuel. For this purpose, two base blends of diesel and biodiesel with and without additives were produced with biomethanol from 0 to 30% (volume basis). Of all the blends, the blends with 5% (volume basis) methanol had the best property profile in terms of density, kinematic viscosity, calorific value, cloud point, and cetane index according to the ISO 8217:2017 standard (DMB grade) in compliance with the IMO requirements for marine fuels. However, the flash point must be increased. The boiling behavior of the blends was also investigated. A cluster analysis was used to evaluate the similarity between the blends based on their different physical properties

Vertical distribution of polycyclic aromatic hydrocarbons in the brackish sea water column: ex situ experiment

Background Oil spills can cause severe damage within a marine ecosystem. Following a spill, the soluble fraction of polycyclic aromatic hydrocarbons is rapidly released into the water column. These remain dissolved in seawater over an extended period of time, even should the insoluble fraction be removed. The vertical distribution of the aromatic hydrocarbon component and how these become transferred is poorly understood in brackish waters. This study examines the vertical distribution of polycyclic aromatic hydrocarbons having been released from a controlled film of spilled oil onto the surface of brackish water. Methods The study was undertaken under controlled conditions so as to minimize the variability of environmental factors such as temperature and hydrodynamics. The distribution of polycyclic aromatic hydrocarbons was measured in the dissolved and suspended phases throughout the 1 m water column with different intensity of water sampling: 1, 2, 4, 7, 72, 120, 336, 504 and 984 h. Results The total concentration of polycyclic aromatic hydrocarbons ranged from 19.01 to 214.85 ng L–1 in the dissolved phase and from 5.14 to 63.92 ng L–1 in the suspended phase. These hydrocarbons were released immediately following a controlled spill attaining 214.9 ng L–1 in the dissolved phase and 54.4 ng L–1 in the suspended phase near the cylinder bottom after 1–2 h. The 2–3 ring polycyclic aromatic hydrocarbons dominated in the dissolved phase (60–80%), whereas the greater amount of 4–6 ring polycyclic aromatic hydrocarbons (55–90%) occurred in the suspended phase. A relatively low negative correlation (rS = –0.41) was determined between the concentration of phenanthrene and suspended matter, whereas a high negative correlation (r = − 0.79) was found between the concentration of pyrene and suspended matter. Despite the differences in the relationships between the concentration ratio and amount of suspended matter the obtained regressions allow roughly to predict the concentration of polycyclic aromatic hydrocarbons

European marine biodiversity monitoring networks: strengths, weaknesses, opportunities and threats

By 2020 EU Member States are obliged to demonstrate achievement of Good Environmental Status (GES) for their marine waters to fulfill the Marine Strategy Framework Directive (MSFD). By the end of 2015, through the Regional Seas Conventions, each EU Member States was required to develop a marine strategy for their waters, together with other countries within the same marine region or sub-region. Coherent monitoring programs, submitted in 2014, form a key component of this strategy, which then aimed to lead to a Program of Measures (submitted in 2015). The DEVOTES FP7 project has produced and interrogated a catalogue of EU marine monitoring related to MSFD descriptors 1 (biological diversity), 2 (non-indigenous species), 4 (food webs) and 6 (seafloor integrity). This details each monitoring activity at the regional and sub-regional level for these descriptors, as well as 11 biodiversity components, 22 habitats and the 37 anthropogenic pressures addressed. The metadata collated were subject to a SWOT (strengths, weaknesses, opportunities and threats) analysis of/to existing monitoring networks across Europe.JRC.D.2-Water and Marine Resource