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With Oil and Gas exploration and production in low temperature arctic environment, new concerns arise concerning the application of the existing design rules for these conditions. Most codes and standards for bolted flange calculation do not include specific rules concerning application at low temperature. Especially, gasket performances under low temperature are neither tabulated nor easily available from other public sources. In this context, in collaboration with TOTAL, SCHLUMBERGER and SAIPEM sponsors, the CETIM has performed a program called ARCTICSEAL to characterize the flange gasket behavior in arctic environment. The goal is to check that gasket references, commonly used by these companies, are still usable under low temperature arctic conditions without main performance loss. The test program involves mechanical and sealing tests performed on 4 gasket types (sheet fiber based, sheet PTFE based, sheet graphite based and graphite spiral wound) with both NPS 8 and NPS 16 gasket sizes. Gasket performances are determined at −60°C, after loading at −25°C. Additional test involving hot/cold thermal cycling ageing (simulation of intermittent hot process fluid in the bolted flange) have also been performed. The result shows the ability of the tested gasket references to maintain good sealing behavior in most cases. Moreover, the hot/cold thermal cycling ageing improves the sealing performances for some of the tested gasket references. Moreover, a dedicated test stand has been developed to study the behavior of NPS 8 flange connection exposed to quick heat-up after exposure to low temperature environment.

Oil exploration in arctic regions is a very complex activity taking place in a sensitive environment, highlighted by social, wildlife and extreme weather conditions restricting operations to a very limited time window based on the opening of the Tundra season regulations which assesse the quality of the ice and snow coverage over frozen tundra, lakes and seas. Thanks to new technologies, oil exploration in the arctic environment takes a great steps in 3D seismic acquisition methods passing from cable recording equipment and the dependence of sensor connectivity to a recording center and replacing this system with a very versatile system of wireless receivers units equipped with GPS positioning and time stamp recording and storing the seismic data “in situ”. This new technology has allowed a high unit count of light receivers to operate in extreme conditions, which in the past was practically impossible given the limitations of the logistical support to carry out this type of operations in remote and difficult access areas. Definitely this technological development has allowed Repsol to explore a larger surface area in a single winter season acquiring high resolution seismic data that allows obtaining high quality images with better geophysical attributes. Seismic sources have also undergone a notable evolution through the use of high productivity techniques of vibrating trucks moving from a set of multiple vibrators to a single vibrator emission getting up to date simultaneous source acquisitions which allows recording more information without waiting for a second set of vibrators or single vibroseis truck to start shaking to emit energy to the ground. The ability to vibrate at the same time with many sets of single vibrators allows operation on frozen sea either with grounded ice or vibrating on floating ice expanding the exploration boundary to the open sea zones. The new technology has made it possible for Repsol to improve the operational capability of the crew without increasing the number of people or increasing the logistical support required to operate in remote and difficult access areas. This technological advance has allowed the improvement of the quality of oil exploration using 3D seismic techniques reducing the price per recorded trace or per surface source, increasing the possibility to acquire larger surfaces and better seismic data in a single winter season window. More importantly, these technologies have allowed affordable oil exploration with a high respect for the communities, the wildlife and the environment.

International audience; Coldness contributes significantly to the representation and definition of the Arctic. Thus, in a context of global warming, does the Arctic not reduce mechanically? Similarly, its common social representation associates it with a low-density settlement and traditional economies. Does accelerating integration of the boreal regions not affect their degree of nordicity? The index of nordicity of Louis-Edmond Hamelin dates back to the 1960s and the author has already pointed out effects of retraction and extension (Hamelin, 1968). This composite index still holds a special place (Petrov, 1977). It combines 10 criteria: one is latitude, six concern physical environment and, four concern human environment. For each of them, a place takes points according to its degree of nordicity. Finally, the sum of all its points forms its polar value. L.-E. Hamelin thus defined 'isonorths', lines of equal degree of nordicity, the one of ‘200’ laying the southern limit of the Arctic. We are attempting to update this index using as much as possible abundant, global and free downloadable databases. In order to get a view of spatio-temporal evolution of the ‘isonorths’, the nordicity index is calculated for the years 1960 and 2010. This presentation focuses on the first part of this work, which concerns the physical environment, ie 6 out of 10 criteria. A raster with a spatial resolution of 25 km x 25 km is developed for each criterion. Then, a conversion of the data into points of nordicity is carried out according to a matrix adapted from L.E. Hamelin. Finally, the new raster is added to the stack to make the final sum. The results for the environmental criteria show, on the scale of the Arctic basin, a retreat towards the north of the isonorths. Regional disparities appear and are discussed. The case study of Western Siberia for which all the criteria have been calculated could be presented.

Glaciers in the fjords of Svalbard have been receding over last decades. Tempelfjorden, a typical glaciated fjord in West Spitsbergen (78°24′06″ N, 17°02′30″ E), has been sampled in summer 1995 and 2001–2007 for modern benthic foraminifera. We have normalized the abundances and unified the taxonomy of all these published and unpublished data sets and then compiled the record of foraminiferal assemblages changing over years into a comprehensive database. The record includes data on living and dead abundances of benthic foraminiferal species in the surface sediments (0–2 cm) and downcore abundances of living foraminifera (only for 2004). This database portrays benthic foraminifera, this key group of microfossils, in a gradually changing Arctic environment.

Leachate from a humidity cell experiment provided a geochemical framework to evaluate the early evolution of weathering of the same waste rock in an Arctic environment. Comparison of laboratory and field results indicates the hydrogeochemical system within the higher sulfide (0.01–0.27 wt.% S) waste rock pile has attained a peak weathering state, indicated by a shift to acid neutralization by weathering products of Al-bearing minerals, stabilization of the pH near 4.5, mobility of metals from sulfide and Al-bearing minerals, and a highly correlated relation between SO 4 release and outflow from the waste rock pile. Further weathering of the waste rock should be driven by external environmental factors of temperature and precipitation/infiltration instead of internal factors of wetting and transient acid-neutralization processes. An evaluation of sulfide depletion indicates that 4% of the sulfide in the 4 . Weathering is strongly seasonal because of the Arctic climate, which produced a daily sulfide-depletion rate corresponding 0–0.02% and a peak annual depletion of 100 kg or 1.5% of the remaining sulfide content in the

Reliability, availability, maintainability and supportability analysis is an important step in the design and operation of production processes and technology. Historical data such as time between failures and time to repairs play an important role in such analysis. The data must reflect the conditions that equipment has experienced during its operating time. To have a precise understanding of the conditions experienced, all influence factors on the failure and repair processes of a production facility in Arctic environment need to be identified and collected in the database. However, there is a lack of attention to collect the effect of influence factors in the reliability, availability, maintainability and supportability database. Hence, the aim of this paper is to discuss the challenges of the available methods of data collection and suggest a methodology for data collection considering the effect of environmental conditions. Application of the methodology will make the historical RAMS data of a system more applicable and useful for the design and operation of the system in different types of operational environments.

The legal regulations on environmental issues that arise in the Arctic due to intensive exploitation of its oil and gas resources need to be explored. There are gaps in environmental regulations over the Arctic region both at international and domestic levels. For Russia, at least two basic problems can be seen in the legal norms: the absence of a coherent approach to the Arctic environmental legislation and policy, and the need to develop effective mechanisms of environmental protection in the process of the Arctic development. In recent years, the Arctic states have expanded legislation on the Arctic issues. Currently, the most effective legal instruments targeting the protection of the fragile Arctic environment have been created by the Arctic countries. The introduction of a system of integrated environmental management is the first step that should be taken. Deep scientific research should be the obligatory foundation of any Arctic project. Moreover, much attention should be paid to the analysis of biological diversity preservation schemes. Lastly, special laws are needed in Russia to ensure: the regulation, prevention, and response to pollution by oil and other containments; the protection and rational use of Arctic resources; and the conservation of the Arctic marine areas and natural landmarks. These ideas are based on a comparative analysis of the legal rules contained within the laws of Norway, Canada, and the United States.

Shorebirds seem to have evolved a number of strategies for adapting to and exploiting the unpredictable and inhospitable Arctic environment. Two such strategies put forth by Holmes and Pitelka suggest that species either conservatively or opportunistically select breeding locations based on local environmental conditions. “Conservative” species were characterized by strong site fidelity and territoriality, consistent population densities, relatively even spacing of individuals, and monogamous mating systems, while “opportunistic” species exhibited opposite traits and were polygamous. Here, we assessed whether 10 shorebird species consistently exhibited these settlement strategies over a 10-year period (2003–2012) near Barrow, Alaska, by comparing annual estimates of site fidelity, territoriality, and population density. Additionally, we determined the relative importance of past and current environmental and social conditions in predicting annual breeding densities of these same species. Data fro...

David Stone, a long-time government scientist in Canada, who began his career doing biological oceanography in northern Canada, played a key role in the development of the Canadian Northern Affairs...

Numerous scientific records of climate indicators and in-depth statistical analyses thereof testify that the impact of the phenomenon of global warming is becoming increasingly evident. Weather patterns have already been severely altered in various regions of the Earth, with the case of the Arctic clearly standing out. As ice coverage in this region maintains its downward trend, the creation of new and significant business opportunities should, however, be noted. Maritime routes that were previously covered with ice packs are now becoming available for shipping; the promise for shorter voyages from Asia towards Europe and/or the Americas (and vice-versa) is enticing to say the least. Additionally, the reduction of ice in the wider arctic region could facilitate the extraction of the numerous natural resources (and especially energyrelated ones) available in all those frozen areas, which were previously widely considered as unsuitable for any type of business.The analysis in hand will briefly highlight the decline of ice coverage in the Arctic and elaborate on its main consequence in relation to the contemporary global maritime transport system: the creation of the so-called "Arctic Passages". Additionally, it will provide a summary of the current regulatory framework associated with the region under discussion and especially the provisions of the International Code for Ships Operating in Polar Waters (Polar Code or PCD). Furthermore, considering petroleum is today the primary marine fuel source within commercial shipping, this analysis will expand upon previous research efforts into how to preserve the arctic environment by limiting the use of such oil fuels. Therefore, it will explore the use of alternative sources, specifically in the form of liquefied natural gas (LNG), as a way to reduce the environmental impact of petroleum spilled within the pristine arctic waters in the event of an accidental discharge, as well as to decrease air pollutants., De nombreux rapports scientifiques sur les indicateurs climatiques et leurs analyses statistiques approfondies témoignent que l'impact du phénomène du réchauffement planétaire est de plus en plus évident. Les modèles météorologiques ont déjà été gravement altérés dans diverses régions de la Terre, le cas de l'Arctique étant clairement visible. Comme la couverture de glace dans cette région maintient sa tendance à la baisse, la création d'opportunités d'affaires nouvelles et significatives devrait cependant être notée. Des itinéraires maritimes précédemment couverts par des banquises sont maintenant disponibles pour la navigation. La promesse de voyages plus courts en provenance d'Asie vers l'Europe et / ou les Amériques (et vice-versa) attire. En outre, la diminution de la glace dans l'ensemble de l'Arctique pourrait faciliter l'extraction des nombreuses ressources naturelles (et notamment énergétiques) disponibles dans toutes ces zones gelées, qui étaient auparavant considérées comme inaccessibles à tout type d'entreprise.L’analyse conduite met brièvement en évidence le déclin de la couverture glaciaire dans l’Arctique et élabore sa principale conséquence par rapport au système de transport maritime mondial contemporain : la création des « passages arctiques ». En outre, elle fournit un résumé du cadre réglementaire actuel associé à la région étudiée, et en particulier les dispositions du Code international pour les navires opérant dans les eaux polaires (code polaire arctique). De plus, compte tenu du fait que l’utilisation du pétrole est aujourd’hui la principale source de combustibles au sein de la navigation commerciale, cette analyse permet d’élargir les efforts de recherche antérieurs visant à préserver l’environnement arctique en limitant l’utilisation de ces carburants. Par conséquent, elle examine l’utilisation de sources alternatives, notamment sous forme de gaz naturel liquéfié (GNL), afin de réduire l’impact environnemental du pétrole déversé dans les eaux arctiques vierges, en cas de déversement accidentel, mais aussi afin de réduire les polluants atmosphériques.

This chapter concludes the examination of the predominant ideas by looking into the security ideas about the Canadian Arctic. It argues that the predominant security ideas about the Canadian Arctic have developed into two main themes—traditional security ideas and stewardship security ideas. The traditional ideas are centred upon the military dimensions of security while the stewardship ideas focus on Canada’s self-appointed role as the guardian of the Arctic environment and mediator between the romantic ideas of the pristine Arctic environment and the economic ideas of the Arctic as a frontier for economic development. Both fall under the overarching umbrella of the predominant security ideas because the notion of protection of Canada’s northern-most frontier region is at the core of narratives for both the traditional and stewardship ideas.

The development of Arctic oil and gas fields requires low temperature high strength steel materials that can resist critical loads in extreme environments. This paper investigates the mechanical properties such as stress–strain curves, elastic modulus, yield strength, ultimate tensile strength, and fracture strain of normal mild steel and high strength S690 steel to be used in low temperatures relevant to arctic environment. Tensile tests are carried out on steel coupons at different temperatures ranging from −80 °C to +30 °C in a cooling chamber. The influences of the low temperatures on the mechanical properties of mild steel and high strength steel are compared and their differences are discussed. Regression analyses are also carried out on the test data to develop empirical formulae to predict the elastic modulus, yield strength, and ultimate strength of the steels at ambient low temperatures. Finally, design formulae are recommended and their accuracies are further confirmed by the test data including those from the literature.

The study on Arctic sea ice change and its influence to the global climate has become one of the most important scientific propositions. It is necessary to development the equipment with high reliability for monitoring Arctic sea ice change. In this paper, we design a low cost and long life ice buoy based on GPS and ARGOS PMT. The MCU of the system adopts low power consumption enhanced 8051 SCM (Single-Chip Microcomputer), which could collect the environmental parameters by all kinds of sensors, such as atmospheric pressure, temperature (air and sea ice), humidity, position of sea ice, and so on. Through optimizing circuit design and adopting intelligent power management method, the system could operate under very low power consumption. Meanwhile, we adopt the supercapacitor to supply the required large electric current of data transmission. By above methods, it efficiently prolongs the batteries life so as to ensure the long life of the ice buoy. Several prototypes of the ice buoy were deployed on the Arctic sea ice one and a half years ago, and some of them have still operated normally until now. The buoys operating status and the data validity indicate that it is an effective means to observe Arctic sea ice environment by deploying this kind of ice buoy.

Arctic tundra vegetation communities are spatially heterogeneous and may vary dramatically from one meter to the next. Consequently, representing Arctic tundra vegetation communities accurately requires very high resolution raster maps (2 total) near the Toolik Lake research area in the Alaskan Low Arctic. The maps were built using a Random Forest model that was trained and tested on 800 ground reference plots, using classes derived from commonly used legends on existing polygon maps of the area. Withheld test plots (25% of dataset) had a balanced map accuracy of 0.57, kappa of 0.47, and weighted (fuzzy) kappa of 0.65. These maps provide high-resolution plant community information that can serve as important baseline reference data for vegetation monitoring and change detection in this rapidly changing tundra ecosystem, and as validation for coarser scale maps. They also permit fine-scale characterization of landscape phenomena such as community-level nutrient dynamics and wildlife habitat suitability in an important Arctic research site. Our approach demonstrates that very high resolution mapping results can be achieved and validated by integrating high-resolution remote-sensing datasets from multiple sensors in a machine learning model trained on simple field reference data.

Modern technologies are used to create competitive performance in industry, and highly specialized personnel are often needed to operate and maintain the technology. However, both the technology and the personnel are influenced by the environment in which the technologies are operated. In this paper we study how human performance is influenced by an Arctic environment in conjunction with a remote location. Based on a literature study, we map Arctic factors and study how they affect human performance in remote locations. The results show that operational and maintenance personnel may be significantly affected by the Arctic conditions. If not taken into consideration during the design phase, human and organizational performance may be significantly affected. Examples are discussed in relation to petroleum production in Arctic locations north of Norway.

Events shape and in turn are shaped by developments in Arctic ocean policy. Nowhere is this truer than of the ever-changing Arctic environment, which is in turn shaping and being shaped by a global demand for secure sources of future oil and natural gas supplies. As the polar ice cap progressively shrinks, and industry interest in the Arctic quickens, Canadians are confronting the challenges of developing their Arctic hydrocarbon resources. In Canada these conflicting objectives have led to innovative regulatory policies accommodating stakeholder desires on the one hand and environmental and economic considerations on the other. The European Union (EU) similarly has multiple objectives intersecting with its Arctic interests.

Thirty nonmetric traits were studied in two cranial series from prehistoric coastal cemeteries on the Chukchi Peninsula (hereafter Chukotka) – Welen (58 crania) and Ekven (107 crania), representing the Old Bering Sea culture. Both series are close not only to modern Eskimos, Chukchi, and Aleuts but also to Tungus-speaking groups. This may be due both to ancient contacts between continental and coastal populations and to their common origin. Comparisons with the Neolithic groups of Baikal and with southern Mongoloids suggest that Eskoaleuts originated in Siberia, and that admixture between migrants from continental Siberia and those from more southern areas of the Pacific coast was one of the key factors in this process. Another factor was adaptation to the extreme Arctic environment.

Protecting Arctic ecosystems against potential adverse effects from anthropogenic activities is recognized as a top priority. In particular, understanding the accumulation and effects of persistent organic pollutants (POPs) in these otherwise pristine ecosystems remains a scientific challenge. Here, we combine more than 20 000 tissue concentrations, a food web bioaccumulation model, and time trend analyses to demonstrate that the concentrations of legacy-POPs in the Barents/Norwegian Sea fauna decreased 10-fold between 1985 and 2010, which reflects regulatory efforts to restrict these substances. In contrast, concentrations of fossil fuel derived PAHs in lower trophic levels (invertebrates and fish) increased 10 to 30 fold over the past 25 years and now dominate the summed POP burden (25 POPs, including 11 PAHs) in these biota. Before 2000, PCBs dominated the summed POP burden in top predators. Our findings indicate that the debate on the environmental impacts of fossil fuel burning should move beyond the expected seawater temperature increase and examine the possible environmental impact of fossil fuel derived PAHs.

1. In species that actively maintain optimal conditions for offspring development, the quality of the breeding site may have a substantial effect on reproductive effort and breeding success. Here, we studied the effect of nest shelter on reproductive costs for incubating female common eiders (Somateria mollissima) nesting in an arctic environment using both a correlative and an experimental approach. 2. The correlative data showed that females that nested in naturally well-sheltered nests experienced milder temperatures, laid larger clutches, provided a more favourable thermal environment for their eggs and had a higher hatching success than those at exposed nest-sites. 3. We added artificial shelters to exposed nest-sites and compared them to unmanipulated exposed nest-sites to examine the effect of nest shelter in females of similar quality. Costs of nesting in exposed sites were greater as evidenced by the reduced female mass loss and more favourable thermal conditions for the eggs at artificially sheltered nest-sites relative to exposed nest-sites. However, there was no difference in hatchings success between artificially sheltered and exposed nest-sites. 4. This study shows even small changes in the climatic conditions at the nest-site can have substantial consequences for reproductive effort, but the association between nest-site quality and breeding success in eiders is due to better quality individuals occupying better nest-sites.

Geografisk Tidsskrift—Danish Journal of Geography 109(2):181–189, 2009 The paper will explore the sense of place in the Thule district, Northern Greenland, including the emotional topography by which people live. The analytical framework is the notion of a nomadic landscape, drawing from the essay on nomadology by Deleuze & Guattari (2004). The nomadic landscape is constituted by a network of spatial centres—or points of reference—from each of which an infinite spatial realm takes its beginning. The ambition is to demonstrate how, in a nomadic landscape, movement is integral to memory, sociability and experience; this is vital to the understanding of present day responses to the reduced mobility owing to changing weather and ice conditions in the Thule district.

Summary Several options (prevention and mitigation) for controlling wax deposition inside production wells operating in an Arctic environment are evaluated. Preventive measures include improved heat retention using vacuum-insulated tubing (VIT), active heating using electrical heating elements inside the well tubing, jet pumps using water as a power fluid, and downhole injection of paraffin inhibitors. In the field cases studied, none of these measures is 100% effective in preventing wax deposition. Mitigation methods include mechanical scraping using wireline tools and hot oiling. Again, the mitigation methods are not completely effective, and even a method with 99% effectiveness can damage the well seriously after several jobs. Cost of the wax jobs and the production downtime during the jobs are added losses. The current study showed that an optimal combination of appropriate prevention and mitigation measures is needed for adequate wax control and maximization of economic returns. Extensive field data (production rates and flowing wellhead temperatures) were collected to develop and tune the well thermal model. Laboratory flow-loop data were obtained for wax-deposition scaleup and predictions. The wax-deposition model was tuned to match the field data, including a production-rate decline attributable to wax deposition. An economic model was developed to evaluate the benefits of VIT with appropriate polyurethane coupling insulation in achieving higher production rates and lower production downtime during the wax jobs vs. the capital expense of the VIT segment. The results showed that it is highly beneficial to run the VIT, at least in the permafrost layer. Additional length of VIT below the permafrost layer has limited benefits.

Between 1994 and 2002, a series of experiments was conducted at Prudhoe Bay, Alaska, aimed at the development of an effective 4D (or time-lapse) gravity technique. Theoretical investigations had pointed out the potential for monitoring water injection in the [Formula: see text]-deep reservoir, but it was not clear that gravity measurements of sufficient accuracy could be made in the arctic environment. During the course of these experiments, new techniques and instrumentation were introduced and perfected for both gravity and position measurements. Gravity stations are located using high-precision global positioning system (GPS) techniques without permanent monuments. Robust methods for meter drift control have improved noise resistance in relative gravimeter surveys. Absolute gravity measurements with a field-portable instrument maintain absolute gravity levels among surveys. A 4D gravity-difference noise of [Formula: see text] standard deviation has been established at Prudhoe Bay for GPS-controlled relative gravimeter surveys. The lessons learned are now being applied to full-scale waterflood monitoring at Prudhoe Bay. The basic technique is applicable to microgravity surveys and 4D microgravity surveys for any purpose.

Surface water samples (river and lake) were collected from the Revelva catchment every summer from 2010 to 2013. This study concerns importance of the use of some analytical techniques for pollutants and parameters determination in Arctic environmental samples based on the example of total organic carbon, phenols, and formaldehyde determination and measurement of pH and electrical conductivity parameters. Significant average concentration levels of formaldehyde were observed in 2012 and reached 0.26 mg/dm3. Furthermore, the highest determined levels of total organic carbon and electrical conductivity were observed in samples collected in summer 2013. The average value of total organic carbon in that year was 9.54 mg/dm3, and electrical conductivity increased to 63.0 µS/cm. The results of surface water samples analyses show an increasing trend in pollutants concentration levels over the years what may suggest that each year the emission of contaminants from lower latitudes is bigger and, consequently, more of them are deposited in the Arctic. Graphical Abstract

Structural crashworthiness with regard to crushing and fracture is a key element in the strength performance assessment of ship collisions in the Arctic. The aim of this study is to investigate the crashworthiness characteristics of steel-plated structures subject to low temperatures that are equivalent to the Arctic environment. The effect of low temperatures on the material properties is examined on the basis of tensile tests. Crushing tests are undertaken on steel-square tubes subject to a quasi-static crushing load at both room and low temperatures. The crushing behavior of the square tubes in this test is compared with ls-dyna computations. It is found that low temperatures have a significant effect on not only the material properties but also the crashworthiness of steel-plated structures in terms of mean crushing loads and brittle fracture. It is suggested that the collision-accidental limit state design of ships intended to operate in the Arctic region should be carried out by taking the effect of low temperatures into account.

This chapter mainly focuses on the offshore oil and gas production in the southwestern Barents Sea, north of Norway, where the current oil and gas activities are focused and discusses other industrial operations as well. The chapter summarizes that a production facility's performance is dependent on the technology the organization and the humans involved in all phases of the life cycle. Modern industrial offshore production facilities are advanced, complex and integrated systems that are designed to safely, economically and continuously facilitate the transportation and processing of the oil, gas and water from the reservoir and the transformation into energy used by society. First the chapter looks on the general goals of production facility operations. Thereafter it discusses how the Arctic climate and locations affect these goals and finally what can be done to overcome the operational challenges in an Arctic environment.

The aim of the study reported herein was to investigate the effects of low temperatures on the crashworthiness of steel-plated structures. A series of material tensile tests were performed to examine the material behaviors at low temperatures. Then, unstiffened steel-plated structure and stiffened steel-plated structure were collided with a cone-shaped drop object to estimate the crashworthiness of steel-plated structures. The material tensile test specimens and test structures were made of Polar class steel for ships and offshore structures which is a sufficient condition of the IACS requirements concerning Polar Class and Strength of Ships. The tests considered room and low temperatures relevant to an Arctic environment and a cryogenic condition. LS-DYNA nonlinear finite element simulations applying a practical approach of modeling techniques were performed to investigate the structural crashworthiness of the steel-plated structures numerically with results of material tensile tests.Copyright © 2015 by ASME

Ringed seals are semi-aquatic marine mammals with a circumpolar Arctic distribution. In this study, we investigate the amphibious hearing capabilities of ringed seals to provide auditory profiles for this species across the full range of hearing. Using psychophysical methods with two trained ringed seals, detection thresholds for narrowband signals were measured under quiet, carefully controlled environmental conditions to generate aerial and underwater audiograms. Masked underwater thresholds were measured in the presence of octave-band noise to determine critical ratios. Results indicate that ringed seals possess hearing abilities comparable to those of spotted and harbor seals, and considerably better than previously reported for ringed and harp seals. Best sensitivity was 49 dB re 1 µPa (12.8 kHz) in water, and -12 dB re 20 µPa (4.5 kHz) in air, rivaling the acute hearing abilities of some fully aquatic and terrestrial species in their respective media. Critical ratio measurements ranged from 14 dB at 0.1 kHz to 31 dB at 25.6 kHz, suggesting that ringed seals—like other true seals—can efficiently extract signals from background noise across a broad range of frequencies. The work described herein extends similar research on amphibious hearing in spotted seals, the results of which were recently published in this journal [Sills et al., J. Exp. Biol., 217, 726-734 (2014)]. These parallel studies enhance our knowledge of the auditory capabilities of ice-living seals, and inform effective management strategies for these and related species in a rapidly changing Arctic environment.

This is accepted manuscript version. Published version available at http://dx.doi.org/10.1017/S003224741500039X This article engages with knowledge management in governing vulnerable polar areas and tourism. Since the 1870’s Svalbard has been a cruise tourism destination. Due to less ice during the summer period, the number of tourists visiting the remote northeast corner of the archipelago has increased significantly and the potential negative impact on this vulnerable natural environment has become an issue. The standard modes of managing these areas have either been to apply the precautionary principle or measures based on scientific evidence. As management models, both principles are however, for a number of reasons contested. This paper argues for a third model, partly practiced based on a form of monitoring knowledge circulating in 'communities of practice' developed over time. This form of knowledge constitute viable expertise for governing and management of the environment-tourism nexus in the areas but needs to be acknowledged as a complementary management platform. The article demonstrates how such monitoring can be done, and suggests some principles for developing monitoring knowledge for administrative and management puposes.

The Meadowbank Gold Project of Cumberland Resources Limited is located 70 km north of Baker Lake in the arid, arctic environment of Nunavut Territory, Canada. With a site annual average temperature of -11C, and 310 mm/year precipitation, the extrapolation of constituent loading rates from laboratory tests is particularly precarious. Three different scales of kinetic leaching tests were performed on waste rock samples: 1-kg and 100-kg laboratory leaching cells and 250-kg field cell tests. Field tests yielded considerably slower rates of buffering capacity depletion and sulfide oxidation than laboratory-derived rates, although the differences were not consistent between the various test scales. Additional

Reindeer, Rangifer tarandus, are terrestrial herbivores used by Alaskan Native herders for both subsistence food and commercial export. Reindeer are a renewable resource and as part of the food system are monitored for Mercury (Hg) levels in relation to the changing Arctic environment. In this study, both free-ranging reindeer from the Seward Peninsula, Alaska, and reindeer reared at the University of Alaska Fairbanks were analyzed for total mercury (THg) in their hair. Free-ranging reindeer of the Gray herd had mean hair THg levels of 75.4 ng g?1 (n=15), whereas the Noyakuk herd had mean THg levels in hair of 40.3 ng g?1 (n=12). The mean level in hair for THg in the university herd was 15.4 ng g?1 (n=46). Methylmercury also was analyzed in selected samples from both herds; the mean for the Gray herd (37.6 ng g?1, n=5) was higher than the mean for the Noyakuk herd (20.7 ng g?1, n=2). Higher THg concentrations in the Gray and Noyakuk herds, when compared to the UAF herd, support the hypothesis that reindeer with higher lichen and willow levels in their diet have higher levels of THg.

Since 1998, BHP Billiton has mined diamonds at the Ekati Diamond Mine™ near Lac de Gras in the Northwest Territories of Canada. Current operations are based on mining multiple pipes by the open-pit method, but as some pits deepen, converting to underground mining is being considered. As a test of underground mining methods and to provide access to the lower elevations of the Panda and Koala pipes, the Koala North pipe is being developed for underground mining. Initially, the top 40 m of the pipe were mined as an open pit to provide grade information and a prepared surface for the transition to underground mining. Currently, Koala North is being developed as an open-benching, mechanized, trackless operation. Although the method was successfully used at several De Beers diamond operations in South Africa, it has never been tested in an Arctic environment. This case study describes basic geology, mining method layout and ongoing geological and geotechnical investigation. From the beginning of underground development, geotechnical daily routines have been fully integrated within the technical services department, which supports the operation. Geotechnical, geological and structural information obtained from underground mapping and core logging is compiled, processed, reviewed and analyzed on site by the geotechnical staff. Conclusions and recommendations are implemented as part of the operations in a timely manner. This ongoing “live” process enables the operators to make the most efficient use of resources both for ground support and excavations as well as to address safety issues, which are the top priority.

Mandibular dislocations are rare in archaeological samples. This paper describes an unreduced dislocated mandible in an adult male skeleton from Point Hope, Alaska. The left mandibular condyle has been displaced anteriorly and two new articulations for the left coronoid process and remnant of the left condyle have formed. The left mandibular body and ramus exhibit severe atrophy, and all of the mandibular teeth have been lost antemortem. A review of historical accounts from the early contact period reveals that the Alaskan Eskimos suffered from a variety of disabilities of the musculoskeletal system. Despite these disabilities, however, many of these individuals were able to function with little or no assistance from other members of their group. The fact that this individual survived to an advanced age in the harsh arctic environment is a testament to the body's remarkable ability to compensate for and survive with physical disabilities. Copyright © 2003 John Wiley & Sons, Ltd.