Marine geodesy— a direction for the future

The sensitivity of the ocean mixed layer response to different parameters such as model horizontal resolution, vertical temperature gradient and eye size is investigated in response to moving Indian Ocean cyclone. For this, a one and one-half layer wind-driven reduced-gravity ocean model is forced with synthetic cyclonic vortex. The sensitivity studies are carried out for a cyclone moving along idealized tracks, initially and then for three observed cyclones (TC 01A), (TC02B) and (TC04A) during 2004. Increasing model resolution resulted in stronger ocean response. The role of initial vertical temperature gradient in modulating the ocean response is found to be important.     

Obtaining a social licence for MPAs – influences on social acceptability

The biological success of Marine Protected Areas (MPAs) depends to a large extent on their social acceptability, sometimes referred to as a social licence. Local resistance has slowed international progress towards a global network of MPAs. The causes of local resistance and limited social acceptability are poorly known, which constrains the development of new planning paradigms that could address these issues. Two case studies in New South Wales, Australia determined the factors that influenced community attitudes towards MPAs. The Port Stephens-Great Lakes Marine Park (PSGLMP) and Batemans Marine Park (BMP) underwent virtually identical and concurrent planning processes, however resistance to the BMP was more intense and sustained. Differences in the demographics, history, local media coverage and social impacts of each marine park contributed to these different community responses. The BMP demonstrated the ‘perfect storm’ of opposition triggers – a community struggling in the transition away from a primary production economy, a highly politicised media dominated by powerful elites with ideological objections to the park, and social impacts sufficiently profound to motivate local citizens to support an active campaign against the park. These impacts included loss of access, identity and increased competition for resources. This research points to the importance of developing a deeper understanding of the social, cultural and political landscape of the communities in which MPAs are proposed and a rethink of planning processes to better incorporate community objectives and knowledge.     

Green’s function approach for calibrating tides in a circulation model for the East Asian marginal seas

A simple effective method of inverse estimation provided by model Green’s functions is examined to calibrate tides in a regional circulation model for the East Asian marginal seas. The Green’s function optimization derived by perturbing the model parameters significantly improves the estimate relative to observation as compared with baseline integration. Among the optimized model parameters, the largest effects on cost function reduction come first from the harmonic constant of M₂ along the open boundaries with the optimized values of 89.7 ± 0.8% for amplitude, and second from the bottom friction with the optimized value of (3.06 ± 0.08) × 10⁻³.     

Inferred gas hydrate on the Barents Sea shelf — a model for its formation and a volume estimate

 On the southwestern Barents Sea shelf, sediments containing gas hydrates that overlie free gas have been inferred from multichannel seismic data. The volume of suspected gas hydrate is tentatively estimated to about 1.9×10⁸ m³. The gas hydrate zone probably formed from thermogenic gas leaking from a deeper source. The hydrate zone may have thickened during the Neogene by including gas originally trapped as free gas below the hydrate following a significant downward migration of the isotherms caused by erosion and/or subsidence. Within the present oceanographic conditions, gas hydrate is suspected to be stable or slowly decomposing. Received: 20 December 1996 / Revision received: 20 August 1997     

Upgrading or unhelpful? Defiant corporate support for a marine protected area

Fishing firms sometimes give political support to marine conservation measures that seem contrary to their commercial interest. To explain this apparent paradox, an analysis is made of the stance taken by a New Zealand company in response to a proposed marine protected area in the Ross Sea. The firm defected from its industry’s opposition to the proposal, choosing to support the reserve. The analysis uses concepts from corporate political strategy to identify why such support might be forthcoming, and under what conditions. The article argues that a firm endorsing a conservation initiative in defiance of its industry intends to engineer a redistribution of profit and control within its global production network, regardless of any public benefit. While there was in this instance a public benefit in the form of potential environmental upgrading, the firm’s strategy risks compromising the effectiveness and impartiality of marine governance organizations.     

Collection of mussel worms Pseudonereis variegata for bait — a legislative anachronism

The extent of damage caused to mussel and tube-worm Gunnarea capensis beds by the collection of mussel worms Pseudonereis variegata for use as bait is assessed. Between 0,4 and 5,0 m² of mussel bed and 0,7 m² of tube-worm reef is destroyed in the collection of the legal limit of 20 mussel worms. Such destruction has implications for ecological succession and is at variance with legislative restrictions governing the collection of mussels.     

Attitude determination using a multi‐antenna GPS system for hydrographic applications

A four‐antenna GPS attitude determination system was used to estimate roll, pitch, and heading parameters of a 52‐meter surveying vessel in an operational marine environment. The least squares algorithm for platform attitude estimation using multiple baseline vector observables is presented. An efficient on‐the‐fly carrier phase ambiguity searching method is derived, which utilizes the Cholesky decomposition method and the known baseline constraints between the GPS antennas to construct the potential ambiguity sets on the sphere. The accuracy of the estimated attitude parameters from the GPS multi‐antenna system was assessed with an independent inertial navigation system (INS). Results from sea trials show that the proposed GPS multi‐antenna system and processing algorithms delivered a satisfactory performance under various ship maneuvers. The accuracy of GPS estimated ship attitude parameters is better than 0.06 degrees at an output rate of 10 Hz. Such a performance demonstrates a new alternative means to provide accurate, reliable, and cost‐effective ship attitude information for hydrographic applications.     

Mammalian neuropathology: a paradigm for the study of teleost neurotoxicity?

In vertebrates, neurotoxicants are chemicals whose primary toxic effect is on the nervous system, either the central nervous system (CNS {brain and spinal cord}) or the peripheral nervous system (PNS {spinal roots, sensory ganglia, peripheral nerves}). Pathological aspects of neurotoxicity are well documented in experimental mammals. We illustrate the neurotoxicity of two chemicals, which both produce lesions in selective regions of the rat brain, a thiocarbamate herbicide (cycloate) and an industrial chemical, chloropropionic acid (L-CPA). Cycloate exposure results in neuronal cell death by apoptosis in specific areas of the forebrain, whereas L-CPA produces granule cell necrosis in the cerebellum. Our studies in rodents demonstrate the discriminative power of neuropathological tools for neurotoxicity. Many agrochemicals/industrial chemical products enter the aquatic environment, some with the potential for neurotoxicity. The teleost CNS is the most primitive among the vertebrates but has features in common with the CNS of more advanced forms. Even allowing for differences in phylogenetic organisation, neuropathological tools should have the potential to identify neurotoxicants that affect teleosts.     

Who gets what? Developing a more equitable framework for EU fishing agreements

The reform of the European Union’s Common Fisheries Policy (CFP) is focusing attention on EU distant water fishing activities, including the agreements signed with developing coastal states. Here, the EU’s fishing agreement with Madagascar, among the poorest countries to hold such an agreement, is examined. Incomes received by Madagascar since the first agreement with the EU in 1986 are documented, in both nominal and real terms, and discussed in the context of other conditions tied to the agreement, in particular support provided by the EU to improve Madagascar’s fisheries management capacity. Results indicate that since 1986, EU quotas increased by 30% while the fees paid by the EU decreased by 20%. Yet, Madagascar’s treasury income from these agreements decreased by 90%. This shows that the EU agreements with Madagascar are in direct contradiction to the goals set forth by the CFP, which states that benefits of agreements should be directed towards developing countries, and not towards private EU entities. This raises profound ethical questions that the CFP reform must address. A new framework is proposed, prioritizing fisheries sustainability and equitable benefit sharing, in which reasonable quotas are set, fees are indexed to the landed value of catches, and all costs of agreements are borne directly by the benefiting industries. EU development assistance should be decoupled from these agreements, and should focus on enhancing the host countries’ monitoring and enforcement capacities. This new framework would increase the benefits to Madagascar while reducing costs to EU taxpayers.     

Grouping Small Spacecraft for Global Meteorological Observations Using a Microwave Radiometer–Spectrometer

Izvestiya, Atmospheric and Oceanic Physics - The current state of microwave radiometry for remote sensing of the Earth is considered. There are currently some 30 satellite microwave radiometers...     

A note on a critical wind speed for air–sea boundary processes

Wind and wind-generated waves were measured in a wind-wave tank. A clear transition was found in the relation between the wind speed U ₁₀ and the wind friction velocity u _* near u _* = 0.2 m/s, where U ₁₀ is the wind speed at 10 m height extrapolated from the measured wind profile in a logarithmic layer, and u _* = 0.2 m/s corresponds roughly to U ₁₀ = 8 m/s in the present measurement. Quite a similar transition was found in the relation between the spectral density of high frequency wind waves and u _*. These results suggest the existence of the critical wind speed for air–sea boundary processes, which was proposed by Munk (J Marine Res 6:203–218, 1947) more than half a century ago. His original idea of the critical wind speed was based on the discontinuities in such phenomena as white caps, wind stress, and evaporation, which commonly appear at a wind speed near 7 m/s. On the basis of the results of our present study and those of earlier studies, we discuss the phenomena which are relevant to the critical wind speed for the air–sea boundary processes. The conclusion is that the critical wind speed exists and it is attributed to the start of wave breaking rather than the Kelvin–Helmholtz instability, but the air–sea boundary processes are not discontinuous at a particular wind speed; because of the stochastic nature of breaking waves, the changes occur over a range of wind speeds. Detailed discussions are presented on the dynamical processes associated with the critical wind speed such as wind-induced change of sea surface roughness and high frequency wave spectrum. Future studies are required, however, to clarify the dynamical processes quantitatively. In particular, there is a need to further examine the gradual change of breaking patterns of wind waves with the increase of wind speed, and the associated change of the structure of the wind over wind waves, such as separation of the airflow at the crest of wind waves, the turbulent stress, and wave-induced stress. Studies on the dynamical structure of the high frequency wave spectrum are also needed.     

Development of a real-time PCR method for Thalassiosira rotula rapid detection

Gene specific primers and DNA probe were designed based on the sequence of 18S rDNA cloned from the red tide alga Thalassiosira rotula. A real-time fluorescent quantitative PCR (RFQ-PCR) method was developed for quantitative detection of T.rotula. The RFQ-PCR assay data showed that the results obtained with the RFQ-PCR quite good agreement with those with the light microscope (LM) counting method, which suggested that the RFQ-PCR could be a useful method for red tide alga detection.     

Microform bed clusters as refugia for periphyton in a flood‐prone headwater stream

Flood effects on benthic algal communities grown upon three common substratum types were assessed in a gravel‐bed stream. Microform bed clusters (MBCs) and, to a lesser extent, boulders conferred resistance on their associated periphyton communities (i.e., reduced flood‐induced biomass loss; functioned as refugia) relative to cobble/gravel substrata. On all substrata, flooding significantly reduced the relative abundance of Diatoma hiemale, and increased the relative abundance of Gomphonema minutum f. syriacum and/or Ampithrix sp. Long‐term (>4 months) sampling indicated that MBCs generally supported more algal biomass than did boulders, which, in turn, supported greater biomass than cobbles/gravels. Manipulation of the abundance of refugial structures (e.g., MBCs) could possibly alter productivity of flood‐prone gravel‐bed streams. Stream periphyton biomass models may be improved by explicit consideration of the effects of refugial substrata. The interstitial spaces of MBCs may constitute a unique habitat, and deserve further study.     

The Ryukyu Trench may function as a “depocenter” for anthropogenic marine litter

While concern over anthropogenic marine litter around coastlines is increasing worldwide, information on this litter in trenches on the seafloor is very sparse. We investigated the amount of marine litter on the deep-sea bottom around the Ryukyu Islands in the Northwest Pacific, based on trawl samples. The density of litter observed in the axis of the Ryukyu Trench (7100 m) and in the basin of the Okinawa Trough ranged from 1.2 × 10³ to 7.1 × 10³ items km^?2, or 7.5–121.4 kg km^?2, which was significantly higher than that observed on the adjacent shallower continental slopes or abyssal plain (0.1 × 10³ to 0.6 × 10³ items km^?2; 0.03–9.2 kg km^?2). This suggests that trenches and troughs function as “depocenters” for anthropogenic litter because of their deeper and enclosed topographies.     

A combined thermographic analysis—Neural network methodology for eroded caves in a seawall

An application of an artificial neural network (ANN) combined with thermographic analysis for estimating the depth of eroded caves in a seawall is presented in this paper. A model experiment was first conducted in a sandbox using a thermographic device to detect the interior conditions of a structure from its temperature changes measured on the surface. The temperature difference calculated from the air temperature and the measured concrete surface point on a thermographic image was obtained for the neural network. Based on the laboratory data, an optimum ANN model for the estimation of the depth of eroded caves in a seawall was established by using four input factors: the site temperature, humidity, thermographic area, and the temperature difference. The model was verified using data from a seawall in Tainan City, Taiwan. From the results, it was found that the present ANN model efficiently estimates the depth of eroded caves in a seawall.     

Optimal Design for Main Dimensions of a 75000t Floating Production and Storage Vessel

The basis, process and results of the demonstration of the main dimensions of a 75000t floating production and storage vessel are discussed in this paper. A simple but reliable orthogonal design method is applied in the main dimension optimization. The ideas of gradual approximation and feedback from various aspects are put into effect. During the demonstration, in order to make the model tally with the actual situation, the draft design is closely related to the computational analysis, so that the demonstration model can be verified at any time; the handling of the overall system is closely related to the research of each item, which is beneficial not only to the mastery of various regularities, but also to the balance of decisions. Finally, according to the computational results and the regularities obtained from analysis, the main dimensions are determined.     

Inhibition of P-glycoprotein transport: a mechanism for endocrine disruption in the channel catfish?

P-glycoprotein (pgp), an efflux transporter localized in a variety of tissues including the intestinal mucosa, renal tubules and bile canaliculi, is known to participate in the disposition of a variety of chemicals, including steroid hormones. This study examined the relationship of pgp to the movement into the bile of the hormone estradiol (E2), and the potential for transport interactions between the environmental pollutant nonylphenol ethoxylate (NPE) and E2. Biliary-cannulated in situ-prepared isolated perfused livers were used to assess pgp transport function. E2, in competitive transport preparations with Rhodamine 123 (Rho123), a pgp substrate, demonstrated significant decreases in Rho123 transport into bile, as did the prototypic inhibitor and substrate verapamil. [3H]E2 (0.28 nM) transport into bile was significantly reduced with either 20 M NPE or verapamil. These results suggest that E2 is a substrate and/or modulator for the catfish biliary pgp transporter, and that NPE potentially influences biliary transport and excretion of E2.     

Human dignity: A fundamental guiding value for a human rights approach to fisheries?

Recently, a human rights approach has been center-staged within fisheries governance as a response to the limits of private property rights in reducing insecurity and vulnerability among fishers and fishing communities. Despite its growing adoption in international legal frameworks and among civil society organizations, the conceptual pitfalls of the human rights approach to fisheries (i.e., its neoliberal tendencies and the neglect of collective rights and social duties) raised by critical scholarship remain largely unsettled, leading to practical concerns about whether such a framework will ultimately benefit fishers on the ground. To further contribute to the debate, this article presents a nuanced discussion of the human rights perspective by introducing the concept of human dignity. Specifically, it argues that human dignity, with its greater conceptual scope and depth, could act as a foundational value with which to mitigate some of the shortcomings of the human rights approach. The purpose here is suggestive rather than definitive and is aimed at highlighting the link that has not been clearly made between human rights and human dignity. I argue that heightened attention to human dignity has the potential to create wider support for the human rights approach and ultimately help facilitate its efficacy in fisheries.     

The dispersion relations for surface plasmon in a nonlinear—metal—nonlinear dielectric structure

In the asymmetric and symmetric nonlinear--metal--nonlinear dielectric structures, this paper studies the analytic dispersion relation for surface plasmon in a system consisting of a thin metallic film covered on two sides media of intensity-dependent refractive indexes by applying a generalised first integral approach. Especially in the symmetric waveguide structure, two possible modes can exist: the odd mode and the even mode. The dispersion relations of the two modes are obtained. Due to the nonlinear dielectric, the squared magnitude of the electric field at the interface appears and alters the dispersion relations. Numerical results are compared to those from a certain approximate treatment.