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1.
This paper summarizes the interim Phase II results of the Arctic Tanker Risk Analysis Project, which examined the risk of oil shipment by tankers in the Canadian Arctic. The objectives were to identify the hazards most likely to produce an oil spill on the MV Arctic, and to institute measures to reduce that risk. Phase I indicated that a high potential exists for a shipping accident at the terminals, the St. Lawrence River and in the High Arctic. However, environmental sensitivity was shown to be greatest along the coastal zone of the Gulf of St. Lawrence and the St. Lawrence River. Phase II involved further examination of environmental sensitivity and the task of ice navigation. These results resulted in a revised risk profile. Three spill scenarios were then designed to estimate clean-up costs and other economic impacts. A cost effectiveness analysis was conducted which compared spill costs to risk mitigation. As the project enters Phase III, the scope has widened to include all product tankers operating in the Arctic. A new Canadian Standards Association Risk Management Standard Q850 is being implemented with the objective of providing prototype tanker Bridge Risk Management System software.  相似文献   

2.
Responding to the world’s growing demand for oil and gas, Arctic resources have been given much attention by the energy and shipping industries. In addition, global warming has accelerated oil and gas development in the Arctic, particularly in its western region. Ice-diminishing Arctic has inspired the world’s shipping industry to explore the feasibility of the historical Arctic routes, the Northwest Passage and Northern Sea Route, as seasonal commercial sea lanes. The background aspects of the Passages and the main issues to be solved for their commercial openings are discussed in this paper. Challenges to an internationally agreeable Arctic regime, likely the Antarctic Treaty, are crucial for clean production and safe transport of the Arctic resources and the transit passages across the Arctic Ocean.  相似文献   

3.
The correlation between areas of open water in ice-covered seas and increased biological productivity has been noted for some time. To date, most attention has been focused on larger polynyas, such as the Northeast Water and the Northwater. Although spectacular in their own right, these large polynyas represent only part of a vitally important continuum of biological productivity that varies significantly between geographic areas and ice habitats, that includes the multi-year pack of the polar ocean and small localized polynyas in annual ice. Surveys of the distribution and abundance of ringed seals in the Canadian Arctic Archipelago have shown differences in density that are correlated with the presence or absence of polynyas. There is also significant variation in the biological productivity of polynya areas of the Canadian High Arctic Archipelago and northern Greenland, all of which receive inflow from the polar basin. Long-term studies of polar bears and ringed seals in western Hudson Bay and the eastern Beaufort Sea show significant but dissimilar patterns of change in condition and reproductive rates between the two regions and suggest that fundamentally different climatic or oceanographic processes may be involved. Projections of climate models suggest that, if warming occurs, then the extent of ice cover in Hudson Bay may be among the first things affected. Long-term studies of polar bears and ringed seals in the eastern Beaufort Sea and Hudson Bay would suggest these two species to be suitable indicators of significant climatic or oceanographic changes in the marine ecosystem.  相似文献   

4.
The Arctic Council, an intergovernmental forum of the eight Arctic states, is currently embarked on a comprehensive assessment of Arctic marine activity in the 21st century — the Arctic Marine Shipping Assessment (AMSA). One of the challenges for theAMSA study team has been to identify the major uncertainties that will be central to shaping the future of Arctic marine use in 2020 and 2050. Using scenario planning, AMSA has identified two primary drivers and uncertainties: (A) Resources and trade; and, (B) Governance. Four scenario narratives have been developed with these two, key uncertainties as the framework elements. The main arguments focus on the fact the Arctic has experienced globalization early in the century and that the global maritime industry has already ventured into the Arctic Ocean. Marine access in the Arctic Ocean is also changing in unprecedented ways and the extraordinary transformation Arctic sea ice is undergoing — thinning, extent reduction, and a reduction in the area of multiyear ice in the central ocean — has significant implications for longer seasons of navigation. However, the high prices of global commodities such as oil, gas, and hard minerals (for example, copper, nickel and zinc) have generated high levels of demand for Arctic natural resources. The Arctic states are challenged by an overall lack of maritime infrastructure to adequately support current and future levels of Arctic marine operations; ports, communications, environmental monitoring, search & rescue, incident response, aids to navigation, and coastal charting, to name a few, require substantial and timely investment by the coastal states and marine operators. A second challenge is the ongoing development of an integrated system of rules and regulations governing Arctic navigation that will enhance marine safety and ensure marine environmental protection throughout the basin. These challenges will require historic levels of cooperation among the Arctic states and broad engagement with the many, non-Arctic stakeholders and actors within the global maritime industry.  相似文献   

5.
The objective of this article is to take stock of integrated management in the Canadian North, assessing its contribution to the advancement of knowledge and practice regarding the role of indigenous knowledge and community-based monitoring. This is done in three steps. (1) The Beaufort Sea, designated a Large Ocean Management Area under Canada's Oceans Action Plan, is used as an example of a consultative planning process, with special attention to indigenous peoples. (2) How specifically can indigenous knowledge contribute to integrated management? The problem of Arctic marine food web contamination is used to illustrate the strengths and limitations of traditional ecological knowledge and its relationship to science. (3) The discussion of community-based monitoring relies on Voices From The Bay study involving the Inuit and Cree of Hudson and James Bay, and Inuit observations of climate change study in the Canadian western Arctic. The examples together address integrated coastal management and the health of ocean ecosystems, showing how stakeholder participation and knowledge helps widen the range of knowledge to understand and help monitor environmental change.  相似文献   

6.
The distribution and diet of larval and juvenile Arctic cod (Boreogadus saida) were studied during summer 2005 in the coastal Canadian Beaufort Sea. A total of 275 individuals were captured and the highest abundance was observed at station depths of 20–30 m. This corresponds well with the location of the frontal zone where the Mackenzie River plume water and open sea water meet. Diet examinations were performed on 220 Arctic cod, which were found undamaged from sampling. We observed a gradual decrease in prey number per fish and increase in prey size as larvae grew which corresponded to a shift from Rotifera and nauplii towards larger copepodid stages. However, at all sizes, the larvae remain generalists and feed on a broad range of organisms. Environmental changes due to climate warming could have a two-fold impact on fish larvae feeding in the studied region. First, the potential for increased primary production may lead to increased zooplankton production that may impact the feeding and nutrition positively. On the other hand, greater discharge of turbid water from the Mackenzie River may reduce light penetration in the water column that may negatively influence the ability of visual predators to successively forage.  相似文献   

7.
方瑞祥 《世界海运》2010,33(8):63-65
以未来15年北冰洋气候变暖以及大量的海冰融化作为背景,分析北极"西北航道"贯通后的巨大经济利益,并对在北冰洋开设新的航线进行了探讨。北极的自然变化过程深刻影响着中国未来海上运输。由于北极地区具有夏季通航的前景,我国应及早动手制订北极战略,研究北极航线,保证最大的经济利益。  相似文献   

8.
There is wide recognition that the process of climate change may be affecting the Arctic region at a faster pace than other regions. What is uncertain is the full impact of climate change on ice cover, and in particular whether there will be a significant decrease of summer ice from the current three months to a longer period and accompanied by navigation conditions suitable and safe for commercial shipping. New international navigation routes through the Canadian and Russian Arctic sectors could significantly reduce the length of sea voyages from Asia to North America and Europe. However, on the basis of what is known to date, there are significant differences of view as to the feasibility of international commercial navigation in the Northwest Passage.  相似文献   

9.
ABSTRACT

Recently, the Arctic Route has become busier with the continuous melting of Arctic ice. However, navigation on the Arctic Route would be much more complex than in normal water as harsh environmental conditions, such as ice-covered water and scarce costal ports that may cause more uncertainty. Nowadays, with the rapid development of sensors on board, more related data has become available. Thus, implementing comprehensive Arctic maritime risk assessment is urgent and necessary in practice. This study proposes an Arctic maritime risk state assessment method including real-time risk state assessment and risk prediction. Specifically, real-time observation samples’ numerical risk state would be firstly obtained with projection pursuit method from 10 risk indicators. Due to the fuzzy uncertainty of single observation set, information diffusion would be applied to provide diffusion estimation on risk probability distribution in order to depict risk state precisely. Also, the accumulated distribution can be regarded as the risk prediction for next time slot and risk entropy is introduced to depict risk tendency directly. Case study based on ‘Yongsheng’ is conducted to demonstrate and verify the effectiveness of the proposed method. The findings can be useful for the operators and management on board during the Arctic voyage.  相似文献   

10.
Primary production events in both the Arctic and the Antarctic are highly localized. Carbon-14 incubations that did not account for this caused antarctic primary production estimates to be revised too far downwards from the historic view of high productivity. The primary production regime in the Arctic is even more heterogeneous than in the Antarctic. Arctic primary production rates are in the process of being revised upwards because of a better spatial and temporal distribution of incubation experiments and a re-awakening of interest in estimating new production from the distribution of chemical variables. Similarly, recent examination of temporal changes in nitrate concentrations and recognition of the importance of ice-edge blooms has caused antarctic primary productivity to be revised upwards. In both the Arctic and the Antarctic, the ratio of “new” to total primary production is high, and neglect of this fact can lead to an underestimation of the potential that these regions have for influencing global cycles of bioactive chemicals. Some recent data on temporal changes in nitrate from Fram Strait emphasize the poor state of our knowledge by suggesting an unexpectedly high “new” production rate of 1 g C m−2 d−1 for a 35 day experiment that encountered an early Phaeocystis bloom. Chemical distributions suggest that new production over the shelf seas that border the Polar Basin is about 50 g Cm−2 yr−1.The shelves in the Arctic Ocean's marginal and adjacent seas comprise 25% of the total global continental shelf. These extensive shallow regions have much higher rates of primary production than the Polar Basin and may be globally significant sites of denitrification. Globally significant silica deposition could occur on these shelves or on the adjacent slopes.Because of the differences in geomorphology and stratification, global warming is likely to increase primary production in the Arctic and will probably decrease antarctic primary production.In addition to sharing high ratios of “new” to total primary production, high ammonium concentrations occur in the Arctic and Antarctic. It is possible that these accumulations arise from a strong repression of nitrification at low temperatures.  相似文献   

11.
Abstract

The Lancaster Sound Regional Study serves as a pilot project for regional planning in the Arctic. Probably the most biologically productive area of all arctic regions, Lancaster Sound represents a unique Canadian heritage. And since it occupies the strategic eastern entrance to the Northwest Passage, the Sound has long been a summer shipping route. Now, proposals are under review that would permit year‐round shipping of oil and gas from the Beaufort Sea by means of ice‐breaking tankers. Also proposed are the exploration and development of possible hydrocarbon reservoirs within the Sound. Actual decisions for the area's use must respect the interests of the native Inuit who have lived there for centuries as well as the preservation of the environment. This paper describes the preliminary phase of the regional planning for the region: the preparation of a public discussion paper to elicit informed comment and opinion on future uses of the Sound. It is a first step toward recommending suitable management and use options for the region.  相似文献   

12.
喷水推进在现代舰艇的应用分析   总被引:4,自引:0,他引:4  
简要介绍了喷水推进的基本原理和优点;列举并分析了喷水推进在现代海军高速攻击艇、隐身型舰艇、高速运输舰、护卫舰和驱逐舰等大中型舰艇、登陆舰及两栖攻击车辆上的应用,归纳了喷水推进在现代舰艇应用的特点;最后就喷水推进未来在我海军的应用作了展望。  相似文献   

13.
Projected reductions in the extent and thickness of the seaice cover in the Arctic Ocean could substantially benefit shipping, perhaps opening the Arctic Ocean as a major trade route. However, despite the economic benefits of such changes, the emergence of such a route through the Arctic Ocean presents a number of challenges to Arctic coastal States and policy makers in general. Of particular concern is the potential for significant environmental damage. Historically, strong objections have been raised over restrictions on navigation for environmental purposes, on the grounds that these run counter to the freedom of navigation enshrined in international law. Notwithstanding this, a broad range of measures exist for those coastal States wishing to address the threat from shipping.  相似文献   

14.
This paper presents new data on distribution patterns of modern benthic foraminifera and other microfossils from the Canadian Arctic, specifically the Beaufort Shelf and slope. The material was collected in June to August of 2004 and is the first of its kind in this area to be collected since 1970. We examined the smaller sizes (45–63µm) as well as > 63µm and discovered that many species had been severely underrepresented in previous studies. Deep sea forms, that had been overlooked previously, were common on the shelf; two species (Elphidiella arctica and Ammotium cassis) appeared in preliminary results to be indicators of methane seepage; and it was possible to make determinations of sea-ice coverage using a combination of foraminifera and tintinnids (planktic ciliates). Our data indicated the presence of many of the same species as previous studies from this area, but improved techniques of sample processing greatly increased the number of specimens and species found (particularly the small deep sea arctic species Buliminella hensoni and Bolivina arctica) which provide much more reliable data for paleoceanographic determinations. One of the primary objectives for this work was to provide baseline data to help determine paleo-ice cover; these data cover a broad range of conditions on the Beaufort Shelf that make it possible to achieve this objective as well as improving what it is known about the assemblages on this shelf as compared to other arctic shelf areas, such as the Siberian Shelf).  相似文献   

15.
The existing risk weighing on vessel, crew and ecosystem in the Arctic and more globally in Polar waters promoted the adoption of the Polar Code (PC) early 2017, a mandatory international legal framework intended for enhanced safety and environmental protection. While the substance of the PC has been extensively analyzed, few studies have focused on the underlying relationships between the PC and underwriters. Based on an extensive literature review, documentary materials and interviews with insurance companies, this article conceptualizes the PC as a “toolbox” and analyzes how underwriters can exploit it in their work within the emerging Arctic market. The PC does not only regulate the navigation in Arctic waters in legal terms, but is also aimed at mitigating risks in the Polar areas through the identification of hazard sources and proceduralization of risk assessment. As a result we observe a certain “Polar Code paradox”. Even though the PC is a risk-based instrument and constitutes a key step for improving ship insurability, it has only limited capacity to assist underwriters in assessing risks and insuring vessels. Marine insurers still face a lack of data and high pending uncertainties leading them to exercise extreme caution with Arctic risks appraisal.  相似文献   

16.
Mercury (Hg) levels in the Beaufort Sea beluga population have been increasing since the 1990's. Ultimately, it is the Hg content of prey that determines beluga Hg levels. However, the Beaufort Sea beluga diet is not understood, and little is known about the diet Hg sources in their summer habitat. During the summer, they segregate into social groups based on habitat use leading to the hypothesis that they may feed in different food webs explaining Hg dietary sources. Methyl mercury (MeHg) and total mercury (THg) levels were measured in the estuarine-shelf, Amundsen Gulf and epibenthic food webs in the western Canadian Arctic collected during the Canadian Arctic Shelf Exchange Study (CASES) to assess their dietary Hg contribution. To our knowledge, this is the first study to report MeHg levels in estuarine fish and epibenthic invertebrates from the Arctic Ocean. Although the Mackenzie River is a large source of Hg, the estuarine-shelf prey items had the lowest MeHg levels, ranging from 0.1 to 0.27 μg/g dry weight (dw) in arctic cisco (Coregonus autumnalis) and saffron cod (Eleginus gracilis) respectively. Highest MeHg levels occurred in fourhorn sculpin (Myoxocephalus quadricornis) (0.5 μg/g dw) from the epibenthic food web. Beluga hypothesized to feed in the epibenthic and Amundsen Gulf food webs had the highest Hg levels matching with high Hg levels in associated food webs, and estuarine-shelf belugas had the lowest Hg levels (2.6 μg/g dw), corresponding with the low food web Hg levels, supporting the variation in dietary Hg uptake. The trophic level transfer of Hg was similar among the food webs, highlighting the importance of Hg sources at the bottom of the food web as well as food web length. We propose that future biomagnification studies incorporate predator behaviour with food web structure to assist in the evaluation of dietary Hg sources.  相似文献   

17.
Climatic changes in the Northern Hemisphere have led to remarkable environmental changes in the Arctic Ocean, which is surrounded by permafrost. These changes include significant shrinking of sea-ice cover in summer, increased time between sea-ice break-up and freeze-up, and Arctic surface water freshening and warming associated with melting sea-ice, thawing permafrost, and increased runoff. These changes are commonly attributed to the greenhouse effect resulting from increased atmospheric carbon dioxide (CO2) concentration and other non-CO2 radiatively active gases (methane, nitrous oxide). The greenhouse effect should be most pronounced in the Arctic where the largest air CO2 concentrations and winter–summer variations in the world for a clean background environment were detected. However, the air–land–shelf interaction in the Arctic has a substantial impact on the composition of the overlying atmosphere; as the permafrost thaws, a significant amount of old terrestrial carbon becomes available for biogeochemical cycling and oxidation to CO2. The Arctic Ocean's role in determining regional CO2 balance has been ignored, because of its small size (only  4% of the world ocean area) and because its continuous sea-ice cover is considered to impede gaseous exchange with the atmosphere so efficiently that no global climate models include CO2 exchange over sea-ice. In this paper we show that: (1) the Arctic shelf seas (the Laptev and East-Siberian seas) may become a strong source of atmospheric CO2 because of oxidation of bio-available eroded terrestrial carbon and river transport; (2) the Chukchi Sea shelf exhibits the strong uptake of atmospheric CO2; (3) the sea-ice melt ponds and open brine channels form an important spring/summer air CO2 sink that also must be included in any Arctic regional CO2 budget. Both the direction and amount of CO2 transfer between air and sea during open water season may be different from transfer during freezing and thawing, or during winter when CO2 accumulates beneath Arctic sea-ice; (4) direct measurements beneath the sea ice gave two initial results. First, a drastic pCO2 decrease from 410 μatm to 288 μatm, which was recorded in February–March beneath the fast ice near Barrow using the SAMI-CO2 sensor, may reflect increased photosynthetic activity beneath sea-ice just after polar sunrise. Second, new measurements made in summer 2005 beneath the sea ice in the Central Basin show relatively high values of pCO2 ranging between 425 μatm and 475 μatm, values, which are larger than the mean atmospheric value in the Arctic in summertime. The sources of those high values are supposed to be: high rates of bacterial respiration, import of the Upper Halocline Water (UHW) from the Chukchi Sea (CS) where values of pCO2 range between 400 and 600 μatm, a contribution from the Lena river plume, or any combination of these sources.  相似文献   

18.
Helicopter-borne sensors have been used since the early 1990s to monitor ice properties in support of winter marine transportation along the east coast of Canada. The observations are used in ice chart production and to validate ice hazard identification algorithms using satellite advanced synthetic aperture radar (ASAR) imagery. In this study we evaluated the sensors' additional capability to monitor the freshwater plume characteristic beneath land-fast ice. During the Canadian Arctic Shelf Exchange Study (CASES) data were collected over the Mackenzie Delta in the southern Beaufort Sea where a buoyant river plume exists. Results showed that the electromagnetic–laser system could describe not only the ice properties but also the horizontal distribution of the freshwater plume depths that decreased in depth stepwise offshore as the flow of the buoyant plume was restricted by a series of ridge-rubble fields running parallel to the coast. Relative to the 2 m mean ice thickness, the plume layer depth varied from zero under mobile offshore pack ice to 3 m inshore of the third set of ridge-rubble fields.  相似文献   

19.
赵津  杨敏 《中国海事》2013,(7):53-54,59
文中分析了东北航道沿途各海域的特点,并通过收集、整理国内外专家对北极东北航道海冰变化规律的研究成果,给出了北极东北航道关键海区及冰情变化趋势。  相似文献   

20.
Climate change is predicted to have particularly challenging impacts throughout the Arctic. For instance, there is a great probability of sea ice melting, leading to increased vessel traffic and oil pollution. Eight major nation-states have vested concerns in the potential opening of Arctic sea routes. They each have pledged to take protective action through the Arctic Council. However, there is still a need to develop an international institution to simultaneously address Arctic marine pollution and protect the needs of these states. This article seeks to design a legally binding regime for oil pollution control in the Arctic. In creating this new regime, we shall utilize several shared design elements of historically effective international regimes and take advantage of the legal innovations of these agreements. Our new regime, entitled the Arctic Shipping and Environmental Management Agreement (ASEMA), will take into account both the economic and environmental interests of the parties involved.  相似文献   

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