The BBNJ Agreement will affect legal frameworks for the conservation of marine biological diversity in various regions of the world ocean and the marine Arctic is no exception. As biological diversity in the marine Arctic is particularly vulnerable, the implications of the BBNJ Agreement for the conservation of biological diversity in the marine Arctic deserves serious consideration. Of particular note is the procedure for an environmental impact assessment (EIA). Given that damage to the environment may be irreversible, it is a prerequisite to conduct an EIA before authorizing planned activities, with a view to preventing environmental harm. An EIA constitutes a crucial element in the conservation of the marine environment, including biological diversity. Hence, this article examines the potential implications of the procedure for an EIA as set out under the BBNJ Agreement for the conservation of biological diversity in the marine Arctic beyond national jurisdiction.
The aim of this article is to examine the implications of environmental norms for fishing by analysing the South China Sea and Chagos Marine Protected Area cases. In so doing, the article considers the link between the regulation of fishing and the protection of marine biological diversity. Specifically, three issues are to be examined: (1) the implications of Articles 192 and 194(5) of the UN Convention on the Law of the Sea for the regulation of environmentally harmful fishing, (2) the implications of Article 194 of the Convention for the fishing rights of a state, and (3) balance between environmental considerations and the fishing rights of a state. In this connection, the article argues that environmentally harmful fishing can be regarded as a key concept when considering the regulation of fishing from the viewpoints of marine environmental protection.
The present paper deals with separation of long-crested regular waves into incident and reflected components. Such methods have been available for several decades for linear waves, but have recently been extended to cover nonlinear waves over horizontal foreshores. The overall goal of the present paper is to extend the separation method for nonlinear regular waves to also cover sloping foreshores. This requires the combination of the existing method with a nonlinear shoaling model. A nonlinear shoaling model was very recently found valid for the shoaling of the primary and bound components in regular waves when the slope angle is positive and mild. In the present paper this shoaling model is utilized and assumed valid also for the de-shoaling of the reflected waves, ie on a negative mild slope angle. However, if the reflected waves are nonlinear the de-shoaling process is much more complicated and will for example cause the release of free waves. Interactions among those free reflected wave components may cause nonlinear interactions not included in the mathematical model. For that reason, the applicability range is limited to mildly nonlinear reflected waves. Using numerical model data with various foreshore slopes, wave nonlinearities and reflection coefficients the reliability of the developed model is examined in detail.
In hydraulic model tests, it is common practice to relate the response of the tested structure to the incident wave parameters at the toe. Estimation of the incident wave parameters at the toe is thus an essential part of the analysis of hydraulic model testing. In many cases, the design conditions at the toe are given by waves that are highly nonlinear or even depth limited. Modelling such conditions requires reproducing the prototype foreshore slope in the model. The present paper provide guidelines on the accuracy of a nonlinear reflection separation algorithm when applied to nonlinear waves over sloping foreshores. A simple methodology has been established to estimate the expected errors on the incident wave parameters.
The present paper deals with overtopping prediction for berm breakwaters in line with the EurOtop methodology. The basis for the paper is the recent advances proposed for EurOtop for conventional breakwaters with respect to the influence of the wave steepness and the crest width. New model tests have been performed to investigate the applicability of these influence factors to berm breakwaters. To cover a white spot in existing data for berm breakwaters, the model tests included wave conditions with very low wave steepness. The results show that the recently developed influence factors for conventional breakwaters also improve predictions for berm breakwaters. Based on this, an additional influence factor for the dimensionless berm width is established. The berm width was in previous studies made dimensionless by the wave height, but the present study indicates that the wavelength is more appropriate.
For the design of the breakwater for the protection of Barra do Dande Ocean Terminal in Angola, a rock armor rubble mound structure was the obvious solution due to the proximity of a suitable quarry. For this type of breakwater there is a close relationship between damage resistance in terms of armor unit size and the required maintenance. Designing for small probability of damage generally infers high construction costs but lower maintenance costs. Breakwater roundheads are generally the most critical part of rubble mound breakwaters. In search of minimum lifetime costs, a stable low-cost solution for the breakwater head was investigated in terms of a three-layer rock armor solution applied in the most critical sectors of the roundhead. The aim was to avoid the production wise and construction wise costly large rock sizes while still maintaining a low probability of repairs. The three-layer rock armor solution applied in the critical roundhead sectors was studied in physical model tests at the Aalborg University Ocean and Coastal Engineering Laboratory, Denmark. This solution means that smaller rocks can be applied as failure occurs at significantly higher damage levels. The three-layer solution was a viable technical and economic solution for the port construction and operation.
Mobilization of residual oil droplets is the key process for enhanced oil recovery. Visualization of the droplet movement at a pore level provides insights on the underlying physical mechanisms. We couple a microfluidic droplet generator and a thin glass capillary to study the movement of oil droplets under salinity gradients with visualization of individual droplet movements. The driving forces that affect the movement of the droplets are discussed. We demonstrate experimentally that oil droplets in micro-confined channels can be mobilized and move against pressure under the concentration gradients of dissolved salts. The gradient-driven movement can be strong enough to drive a droplet through a narrow constriction in the middle of the capillary channel. The droplet movement can be understood by combining a Marangoni stress due to surfactant redistribution, electrostatic interaction and diffusiophoresis. This suggests that the abrupt change of salinity may be one of the physical mechanisms of smart waterflooding.
Despite a list of national and international efforts to harmonise data management procedures, the categorisation of space and time within datasets in marine spatial planning (MSP) has not been addressed so far. This paper proposes a conceptual framework to categorise the spatial and temporal dimensions of data used in MSP and introduces a method to jointly manage non-spatial information and spatial data in the same geographic information system (GIS). The presented categorisation provides easy and intuitive classifications for a more detailed and transparent data description of spatial and temporal data properties, which can be applied both in attribute tables and in metadata. It allows the differentiation of the vertical and the horizontal dimensions, enabling users to focus on operations taking place at specific parts of the marine environment. The categorisation with predefined attribute domains allows space and time based automatic analyses. The inclusion of non-spatial data within GIS repositories ensures the availability of all relevant data in one database minimising the risk of incomplete data. Overall, the framework provides effective steps towards a more coherent data management and subsequently may foster better use of information in MSP processes.
A two-dimensional (2D) Reynolds-averaged Navier–Stokes (RANS) equations solver with k–ω turbulence closure is developed, employing immersed boundary (IB) technique on Cartesian grids. Generalized wall functions are introduced to enhance computational efficiency for problems with high Reynolds numbers. To address existing challenges in applying wall functions within IB methods, a novel, effective and easy-to-implement strategy is proposed. Another distinguishing feature of this turbulent-flow solver is that it employs the highly accurate immersed-boundary generalized harmonic polynomial cell (IB-GHPC) method to solve the Poisson equation for fluid pressure. The new solver is firstly validated by simulating channel flows on both hydraulically smooth and rough walls, achieving excellent agreement with benchmark experimental and numerical studies for various flow parameters including velocity, turbulent kinetic energy and shear stress. For channel flow simulations, our implementation of generalized wall functions using the proposed strategy results in a remarkable reduction of grid nodes by over 80%. Moreover, the solver is applied to simulate flow around both smooth and rough cylinders, producing promising results for drag, lift, and pressure coefficients. Our analysis demonstrates a robust performance of the developed solver in modeling turbulent flows based on Cartesian grids, offering a substantial improvement in computational efficiency for tackling problems involving large Reynolds numbers.
A tension between two opposing forces, that is, the force of division and that of unity, is increasingly sharpened in the law of the sea today. An essential question that arises is how one can protect community interests in the divided ocean. The law of dédoublement fonctionnel advocated by Georges Scelle provides an insight into this question. According to Scelle’s theory of the law of dédoublement fonctionnel, State organs perform a dual function: the national function of protecting State interests and the public service function of safeguarding community interests. The law of dédoublement fonctionnel seeks to reconcile these functions. Scelle’s harmonistic vision of international law is well worth reconsidering in the law of the sea and beyond. This article examines the relevance of Scelle’s theory in the context of the law of the sea and explores two models for the protection of community interests at sea.