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Hydraulic experiments using physical scale models of monopile scour protections typically have high ex-perimental uncertainties and data scattering. These uncertainties may severely affect the accuracy of the experimental results and need to be analysed quantitatively. This paper presents a study on the quantification of experimental uncertainties in monopile scour protection damage tests following the Guide to the expression of Uncertainty in Measurement (GUM) (ISO, 2008). The uncertainty analysis is performed using the three-dimensional damage number S3D and the widely applied STAB number. Through the analysis of the S3D number from individual test and repeated tests, it is found that the uncertainty analysis method for an individual test can be efficiently applied to predict the experimental uncertainty. The wave peak period and the current velocity are identified as the two major sources of uncertainties for the S3D number. The flow turbulence and correlations between input parameters can be neglected when estimating the uncertainty. The uncertainty analysis of the STAB number shows that the experimental uncertainty due to measurement can be up to 5% to 7% of the obtained STAB result. This uncertainty range is wide in comparison with the narrow margin of a dynamic scour protection design in DNV's recent recommended practice (DNV-RP-0618). The uncertainty of the STAB number is more affected by the armour stone density, wave peak period and significant wave height.

Earth’s biodiversity and human societies face pollution, overconsumption of natural resources, urbanization, demographic shifts, social and economic inequalities, and habitat loss, many of which are exacerbated by climate change. Here, we review links among climate, biodiversity, and society and develop a roadmap toward sustainability. These include limiting warming to 1.5°C and effectively conserving and restoring functional ecosystems on 30 to 50% of land, freshwater, and ocean “scapes.” We envision a mosaic of interconnected protected and shared spaces, including intensively used spaces, to strengthen self-sustaining biodiversity, the capacity of people and nature to adapt to and mitigate climate change, and nature’s contributions to people. Fostering interlinked human, ecosystem, and planetary health for a livable future urgently requires bold implementation of transformative policy interventions through interconnected institutions, governance, and social systems from local to global levels.

Abstract E-Motions wave energy converter is a promising device capable of harnessing energy from wave/wind induced roll oscillations onto a generic floating platform, whose development was initiated with an experimental proof-of-concept study that, despite demonstrating the potentialities of the device, also highlighted the need for further developments, aimed at improving its performance and efficiency. This justified a new phase of numerical modelling, where E-Motions was reproduced within the ANSYS® AQWA™ environment, a potential theory-based numerical model widely used in the field of wave energy converter development. The model was setup (first stage) and calibrated (second stage) with experimental data from a proof-of-concept study, carried out on a 1:40 geometric scale, with a good agreement being obtained for the hydrostatic properties (difference below 5%) and hydrodynamic roll response (minimum average error of 2.83°). From a follow-up third stage, focused on comparing eight different hull solutions with similar natural roll periods, it was determined that the half-sphere and trapezoidal prism geometries produced the highest power outputs for the studied conditions (maximum average outputs of nearly 5 kW/m and 8 kW/m, respectively). These two designs were then adapted to a 1:20 geometric scale alongside an updated version of the half-cylinder, which served as a “control” case, and subjected to a final stage of numerical modelling centered on assessing the Power Take-Off’s influence (namely through variable damping and mass) in their performance. Outcomes from this stage denote the necessity of a careful selection of Power Take-Off mass/damping combinations, as a disproportionate relationship could lead to scenarios where the conversion system would stall on one of the superstructure’s sides, moving within a very limited range of the available sliding amplitude. Maximum average power output values reach nearly 24 kW, 30 kW and 18 kW for the half-cylinder, half-sphere and trapezoidal prism, respectively, with a follow-up experimental study being planned for the near future, in order to evaluate the validity of these results.

Abstract Monitoring operations at the seafloor above a storage complex area are required to demonstrate that offshore storage of CO2 in the deep subsurface is safe and effective. Within the framework of the STEMM-CCS project, the Goldeneye area was identified as an offshore experimental site for CO2 storage. In this work, the physico-chemical characteristics of the water column at the Goldeneye site were determined by an in-depth analysis of measurements collated from CTD casts, discrete water samples and seafloor landers. The results showed a clear tidal, seasonal and inter-annual variability in the measured parameters within the monitoring period (Oct 2017- May 2019). Variations in pH and pCO2 over a single tidal cycle were in the order of ±0.008 and ±1.5 μatm, respectively. The temporal variability of water column carbonate chemistry parameters was further defined with the aim to provide a solid background for the discrimination from natural changes of potential impacts of CO2 emissions at the potential storage site. Here, we demonstrated how the combination of new and existing methods and technologies could be used for an effective assessment of water column conditions at a potential offshore carbon storage site.

In nature, a multitude of factors influences the fitness of an organism at a given time, which makes single stressor assessments far from ecologically relevant scenarios. This study focused on the effects of water temperature and predation stress on the metabolism and body mass gain of a common intertidal rock pool fish, Gobius paganellus, addressing the following hypotheses: (1) the energy metabolism of G. paganellus under predation stress is reduced; (2) G. paganellus shows thermal compensation under heat stress; and (3) thermal stress is the dominant stressor that may override predation stress responses. Individuals were exposed to simulated predation stress and temperature increase from 20 °C to 29 °C, and both stressors combined. Physiological effects were addressed using biochemical biomarkers related with energy metabolism (isocitrate dehydrogenase, lactate dehydrogenase, energy available, energy consumption rates), oxidative stress (superoxide dismutase, catalase, DNA damage, lipid peroxidation), and biotransformation (glutathione-S-transferase). The results of this study revealed that predation stress reduced the cellular metabolism of G. paganellus, and enhanced storage of protein reserves. As hypothesized, hyperthermia decreased the aerobic mitochondrial metabolism, indicating thermal compensation mechanisms to resist against unfavourable temperatures. Hyperthermia was the dominant stressor overriding the physiological responses to predation stress. Both stressors combined might further have synergistically activated detoxification pathways, even though not strong enough to counteract lipid peroxidation and DNA damage completely. The synergistic effect of combined thermal and predation stress thus may not only increase the risk of being preyed upon, but also may indicate extra energy trade-off for the basal metabolism, which in turn may have ecologically relevant consequences for general body functions such as somatic growth and reproduction. The present findings clearly underline the ecological importance of multi-stressor assessments to provide a better and holistic picture of physiological responses towards more realistic evaluations of climate change consequences for intertidal populations.

Abstract Within the framework of the STEMM-CCS project, a controlled CO2 release experiment was conducted under real-life conditions in the Goldeneye complex area, a depleted gas field located in the UK sector of the North Sea. Here, the viability of water column monitoring for the detection of the injected CO2 is evaluated. Real-time pH and pCO2 measurements were taken in the water column during the CO2 release experiment. Monitoring was carried out throughout the full water column, from the near-seafloor to the sea surface, in order to assess the spatial extent of the CO2 release. The dispersion of the CO2 plume was strongly influenced by tidal circulation in the area. The strongest signals were detected within 8 m of the bubble stream during low tide. The lowest pH and highest pCO2 values were 7.965 and 942.1 µatm, respectively, corresponding to variations of 16.4% [H+] and 125.6% from baseline values. The pCO2 baseline dynamics of Goldeneye area were assessed by the evaluation of the natural pCO2-O2 covariance. The estimation of seasonal thresholds for anomalous pCO2 (pCO2:O2 ratio May= 1.63 ± 0.04) allowed us to assess with confidence the non-biological origin of the detected CO2 during the release experiment.

AbstractGiven the accelerating rate of biodiversity loss, the need to prioritize marine areas for protection represents a major conservation challenge. The three‐dimensionality of marine life and ecosystems is an inherent element of complexity for setting spatial conservation plans. Yet, the confidence of any recommendation largely depends on shifting climate, which triggers a global redistribution of biodiversity, suggesting the inclusion of time as a fourth dimension. Here, we developed a depth‐specific prioritization analysis to inform the design of protected areas, further including metrics of climate‐driven changes in the ocean. Climate change was captured in this analysis by considering the projected future distribution of >2000 benthic and pelagic species inhabiting the Mediterranean Sea, combined with climatic stability and heterogeneity metrics of the seascape. We identified important areas based on both biological and climatic criteria, where conservation focus should be given in priority when designing a three‐dimensional, climate‐smart protected area network. We detected spatially concise, conservation priority areas, distributed around the basin, that protected marine areas almost equally across all depth zones. Our approach highlights the importance of deep sea zones as priority areas to meet conservation targets for future marine biodiversity, while suggesting that spatial prioritization schemes, that focus on a static two‐dimensional distribution of biodiversity data, might fail to englobe both the vertical properties of species distributions and the fine and larger‐scale impacts associated with climate change.