393 research outputs found

    Monitoring the Norwegian Atlantic slope current using a single moored current meter

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    Monitoring the Atlantic inflow (AI) of warm and saline water into the Nordic Seas (Norwegian, Greenland and Iceland Seas) is of great importance becauce of its impact on climate and ecology in Northern Europe and Arctic. In this study, an observation system for establishment of simple, robust and cost effective monitoring of the AI is validated in the Svinøy section, cutting through the AI just to the north of the Faroe-Shetland Channel. We concentrate on the eastern branch of the AI, the Norwegian Atlantic Slope Current (NwASC), an about 40km wide flow along the steep Norwegian slope. The database is an array of 15 current meters on 4 moorings covering the NwASC over a 2-year period 1998–2000. We test the hypothesis that long-term monitoring of the NwASC can be performed by using one single current meter suitable placed in the flow. The volume flux can then be estimated by construction of simple regression models using the single current meter record as the independent variable. For validation of statistical properties as stability, confidence and stationarity, the time series is split into two 1-year segments: a model period and a test period. Gridded correlation fields between currents and volume transport show correlation maxima in the core of the NwASC, ranging from 0.84 on a daily timescale to 0.97 on a monthly timescale. A more comprehensive correlation/ coherence analysis for each current meter record against volume transport on 7-day timescales, enable us to choose the optimal current meter for a linear regression model with (correlation, slope) coefficients of (0.87, 0.13) for the model period and (0.80, 0.13) for the test period. The similarity of the statistical properties for the model and test periods substantiates the stationarity, stability and robustness of the model. A linear regression model underestimates large fluxes and is thus extended to a second degree polynomia. This improves the curve fitting for strong currents with a minor increase in overall correlation, but is more sensistive and less stable. Overall, we find a linear regression model to be more robust and applicable for monitoring the NwASC. The applicability of a linear regression model as an estimator for volume flux of the NwASC is demonstrated using a 2-year time series, and validated against calculated transport. The calculated transport agrees with the statistical analysis and reveals a noisy fit on daily timescale, while the curves coincide well on both 7- and 30-day timescales with correlation coefficients of 0.84 and 0.86, respectively. On all timescales, the calculated and model transport give an overall mean flow of 4.4 Sv and show fluctuations on timescales of days to months, with the seasonal cycle being the most prominent

    Opening Of New Arctic Shipping Routes

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    Neither the Northwest nor the Northeast Passage has so far become important in international shipping. Nevertheless, the prospects should be re-assessed in light of new circumstances in the Arctic, especially the changing ice situation which makes it possible to envisage a future with drastically increased shipping activity. This paper argues, however, that developments on the two sea routes in question today are not straight forward. In the case of the Northwest Passage, ice problems are expected to remain a major limiting factor for many years and the Canadian authorities are not actively promoting international usage of the route, something which is partly related to legal controversies over the status of the passage. In the case of the Northeast Passage, Russia actively advertises its Northern Sea Route, seeing rapidly improving ice conditions. However, the commercial conditions remain uncertain and necessary investments in icebreakers and infrastructure are so far missing. The Northern Sea Route may, besides its regional usage, especially in the western part, have the potential for limited transits in the most favourable season. The Russian vision of year-round transit traffic seems quite unrealistic within the perspective of this decade

    A Widespread Review of Smart Grids Towards Smart Cities

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    © 2019 by the authorsNowadays, the importance of energy management and optimization by means of smart devices has arisen as an important issue. On the other hand, the intelligent application of smart devices stands as a key element in establishing smart cities, which have been suggested as the solution to complicated future urbanization difficulties in coming years. Considering the scarcity of traditional fossil fuels in the near future, besides their ecological problems the new smart grids have demonstrated the potential to merge the non-renewable and renewable energy resources into each other leading to the reduction of environmental problems and optimizing operating costs. The current paper clarifies the importance of smart grids in launching smart cities by reviewing the advancement of micro/nano grids, applications of renewable energies, energy-storage technologies, smart water grids in smart cities. Additionally a review of the major European smart city projects has been carried out. These will offer a wider vision for researchers in the operation, monitoring, control and audit of smart-grid systems.publishedVersio

    The Responsibility of Farmers, Public Authorities and Consumers for Safeguarding Bees Against Harmful Pesticides

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    The worldwide decline in bees and other pollinating insects is a threat to biodiversity and food security, and urgent action must be taken to stop and then reverse this decline. An established cause of the insect decline is the use of harmful pesticides in agriculture. This case study focuses on the use of pesticides in Norwegian apple production and considers who among farmers, consumers and public authorities is most responsible for protecting bees against harmful pesticides. The extent to which these three different groups consider themselves responsible and the degree to which they are trusted by each of the other groups are also studied. This empirical study involves both qualitative interviews with Norwegian apple farmers, consumers and public authorities and survey data from consumers and farmers. The results show that consumers consider public authorities and farmers equally responsible for protecting bees, while farmers are inclined to consider themselves more responsible. Farmers, consumers and public authorities do not consider consumers significantly responsible for protecting bees, and consumers have a high level of trust in both farmers and public authorities regarding this matter. This study also finds that a low level of consumer trust in farmers or public authorities increases consumers’ propensity to purchase organic food, suggesting that those who do not trust that enough action is adopted to protect the environment take on more individual responsibility. This paper adds to the existing literature concerning the allocation of responsibility for environmental outcomes, with empirical evidence focusing specifically on pesticides and bees.The Responsibility of Farmers, Public Authorities and Consumers for Safeguarding Bees Against Harmful PesticidespublishedVersio

    Context-dependent demographic and genetic effects of translocation from a captive breeding project

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    Translocations are a widespread approach to conserve threatened populations. Given the rapid decline and genetic deterioration of many natural populations, translocations are expected to become even more common in the future. The success of translocations is, however, dependent on multiple context-dependent factors, such as demographic and genetic status, habitat quality and animal behaviour. The Scandinavian arctic fox (Vulpes lagopus) exists in a small, fragmented population that is demographically vulnerable and exposed to inbreeding depression. In the early 2000 s, releases of arctic foxes from the Norwegian Captive Breeding Programme were initiated with the purpose of reintroducing populations to formerly inhabited areas and promoting connectivity. Since 2008/2009, 61 foxes have been released in Junkeren, Norway to re-establish an unoccupied area. We used a combination of field observations and microsatellite genotyping from the release site and two neighbouring subpopulations to investigate (i) the probability of establishment and reproduction for released foxes at the release site and in neighbouring subpopulations, and (ii) the impact on litter size and genetic composition in the recipient populations. Results showed that 18% of the released foxes were established at the release site, or in neighbouring subpopulations and 11.5% reproduced successfully. The extent of post-release dispersal into neighbouring subpopulations was also relatively high (11.5%). During the study period, the number of litters more than doubled in the subpopulations with released foxes contributing 29.5% to this increase, but no clear effect of immigration on litter size was found. There was a slight increase in genetic variation in one of the subpopulations, and a significant decline in genetic divergence between subpopulations. We conclude that despite extensive releases, demographic and genetic effects were highly context-dependent. This study highlights the challenges of reinforcement programmes in small populations and reintroductions to unoccupied sites, especially for highly mobile species in a fragmented landscape. conservation; immigration; translocation; genetic variation; demography; arctic fox; Vulpes lagopus; captive breeding; conservation breeding.publishedVersio

    Modeling of Environmental Fate and Effects of Oil Leakages from Abandoned Subsea Wells Using an Environmental Impact Factor Tool

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    Potential environmental consequences of oil leakages (i.e., continuous uncontrolled releases at low flow rate over a long period of time) need to be taken into consideration in the ongoing development of plug and abandonment (P&A) activities on the Norwegian continental shelf. Regulations of P&A wells employ a “zero leakage” target; however, environmental risk monitoring strategies for permanent abandonment are not yet in place. Predicting and estimating the consequences of adverse environmental impacts through a modeling approach can play a key role in evaluating and monitoring environmental risk. In this paper, we present a modeling study of the fate and effects of an oil leakage from abandoned wells using a theoretical scenario on the Norwegian continental shelf. Environmental impact factors (EIFs) derived from the Dose related Risk and Effect Assessment Model (DREAM), previously designed to characterize the effects of produced water discharges, were used to assess impacts of leakages from abandoned wells. Exposure assessments for the EIFs were modified to include specific hydrocarbon contributions derived from different sized oil droplets from the leakages. Because DREAM is not generally used for chronic low-rate oil releases, an update of the database with chronic predicted no-effect concentrations, as input data for effects modeling, was conducted. In general, EIFs became stable after simulations of 30 d. The area from the release site and up to a few hundred meters southward had the most locations of high impact. Chronic exposure and effects on organisms potentially occurred as a steady-state effect over a long period. Risks, at which more than 95% of species will be negatively affected, appeared surrounding the release site, indicating a need for mitigation measures. These results show that the EIF tool can be used for risk management and P&A regulation by identifying potentially harmful leakages.publishedVersio

    Correlation analysis of two-dimensional gel electrophoretic protein patterns and biological variables

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    BACKGROUND: Two-dimensional gel electrophoresis (2DE) is a powerful technique to examine post-translational modifications of complexly modulated proteins. Currently, spot detection is a necessary step to assess relations between spots and biological variables. This often proves time consuming and difficult when working with non-perfect gels. We developed an analysis technique to measure correlation between 2DE images and biological variables on a pixel by pixel basis. After image alignment and normalization, the biological parameters and pixel values are replaced by their specific rank. These rank adjusted images and parameters are then put into a standard linear Pearson correlation and further tested for significance and variance. RESULTS: We validated this technique on a set of simulated 2DE images, which revealed also correct working under the presence of normalization factors. This was followed by an analysis of p53 2DE immunoblots from cancer cells, known to have unique signaling networks. Since p53 is altered through these signaling networks, we expected to find correlations between the cancer type (acute lymphoblastic leukemia and acute myeloid leukemia) and the p53 profiles. A second correlation analysis revealed a more complex relation between the differentiation stage in acute myeloid leukemia and p53 protein isoforms. CONCLUSION: The presented analysis method measures relations between 2DE images and external variables without requiring spot detection, thereby enabling the exploration of biosignatures of complex signaling networks in biological systems
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