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Arctic sea ice change is one of the critical factors affecting the global climate environment; hence, it is crucial to obtain sea ice thickness with high accuracy while studying polar and global climate change. In the process of using altimetry data to estimate sea ice thickness, the mean sea surface height will bring greater uncertainty to the extraction of sea ice freeboard, which will affect the accuracy of sea ice thickness. Also, the influence of snow cover on radar signal penetration will bring greater uncertainty to sea ice thickness. In this paper, we present a processing chain for sea ice thickness estimation. First, we compare the effect of four different MSS models on the freeboard estimation. Then, considering the incomplete penetration of radar signals and the different speeds of radar signals penetrating the snow layer and the vacuum, the traditional sea ice thickness model is optimized to obtain the sea ice thickness. Compared with the Operation IceBridge (OIB) sea ice thickness, the accuracy of sea ice thickness obtained by the optimized model is better than 0.350 m, with a root mean square error of 0.260 m and a mean bias of 0.048 m. The comparison results show that the combination of the latest DTU18 MSS model and sea ice thickness optimization model effectively improve the accuracy of sea ice thickness. [ABSTRACT FROM AUTHOR]

The on-going reduction of sea-ice in the Arctic is now facilitating maritime activities in areas previously considered inaccessible. Numerous statistics indicate that fishing and tourism are clearly gaining momentum within the wider region under discussion. Furthermore, a certain number of private companies and state-affiliated actors are setting into motion plans for promoting the use of the so-called arctic passages, while certain interesting business projects are already underway; the Yamal LNG Project is for example clearly standing out. As human presence and operations are expected to intensify within that inherently risky region, the first aim of this paper is to qualitatively identify certain business opportunities associated with the Arctic and then highlight their interrelation with the prevailing patterns of maritime traffic. Additionally, on the basis of the report titled 'Arctic Shipping Status Report – Heavy Fuel Oil (HFO) Use by Ships in the Arctic 2019' (ASSR #2) that was released during October 2020 by the Arctic Council's Working Group on the Protection of the Arctic Marine Environment (PAME), it explains the use of the various types of fuels in the region under discussion and highlights certain environmental risks. Finally, it briefly assesses the overall effectiveness of a (proposed) regulatory intervention of completely banning the use of HFO in the Arctic. This initiative can indeed have a positive contribution to protecting the region's pristine environment, but any regulations of this type must also consider the issue of fishing vessels, which are not covered under the scope of International Maritime Organization's (IMO) International Convention for the Safety of Life at Sea (SOLAS) and the International Convention for the Prevention of Pollution from Ships (MARPOL). [ABSTRACT FROM AUTHOR]

Due to the existence of seasonal or perennial sea ice cover, the determination of the Arctic sea surface is more difficult than that of mid-low latitudinal oceans. Focusing on the sea surface height in the ice-covered region, this paper constructs a new Arctic mean sea surface (MSS) model, named SUST22, by combining the measurements from ICESat and Cryosat-2 missions. The lead detection methods of ICESat and Cryosat-2 are first studied and modified to acquire sea surface measurements with better accuracy. The results have shown that the standard deviation of Cryosat-2-derived Arctic sea surface height is about 3–4 cm in 10-km resolution grids, while the value of ICESat is 5–6 cm. Then the MSS construction procedure is discussed and the SUST22 MSS model is constructed. The new model is compared with the other four Arctic MSS models. The best agreement is found between SUST22 and DTU21 with an average difference of −4.0 ± 5.2 cm. These models are also validated by ICESat-2 samples. The average difference between ICESat-2 and SUST22 is 15.8 ± 7.4 cm, which shows that the new model SUST22 presents better consistency with the ICESat-2 than any of the other models. [ABSTRACT FROM AUTHOR]

The rapid evolution of science compels renewal of a knowledge-based policy, particularly in cold regions. In the Arctic and Himalayas, which have undergone a significant climate change, there is a disconnect between scientific knowledge and the practices of policy. The rising air temperatures, decreasing ice and snow, increasing precipitation and plastic waste pollutants and the Atlantification of the Arctic Ocean by receiving warmer and saltier water from the Atlantic Ocean call for scientific research questions to strengthen the linkage between science and policy. The Arctic amplification can have remote impacts on other parts of the globe through oceanic and atmospheric teleconnections. Hence, researchers need to push the frontiers of scientific discoveries through multidisciplinary and collaborative approaches in the Arctic Ocean along with connections to the Third Pole – Himalayas. The overall objectives of this paper are to explore how a comparison of the Arctic and the Third Pole is valuable for understanding the Arctic and global biogeophysical processes in this epoch of anthropogenic climate change; provide a strong linkage between the Arctic scientific research and its relevance to society; and help advance a more sustainable future for the Arctic, the Third Pole and the globe. [ABSTRACT FROM AUTHOR]

The rapid decline of Arctic sea ice has been reminding us the significant impacts caused by global warming. However, the other side of the coin is that this opens a window to utilize the Arctic sea routes in the summer seasons, bringing remarkable economic benefits for ocean transportation between Asia and Europe. However, commercial vessels with low ice classes must tackle substantial environmental challenges in the Arctic sea routes, particularly those caused by variable sea ice, even in the melting seasons. Therefore, the science-based support for shipping safety in the Arctic sea routes is being given more prominence. Emerging satellite remote sensing technology plays a critical role in environmental monitoring in the Arctic. This paper reviews state-of-the-art satellite observations on monitoring sea ice and potential applications on supporting shipping activities in the Arctic Ocean. Moreover, we introduced a recently developed system based on satellite observations to support the safe transportation of Chinese cargo vessels in the Arctic northern sea route, demonstrating the efforts by both the science and business communities to promote the development of the polar silk road. [ABSTRACT FROM AUTHOR]

This paper discusses the state of the Arctic cryosphere during the second half of the twentieth century and describes major findings of observational evidence since the 1950s. Although glaciers have been retreating steadily from their Little Ice Age maximum positions for decades, Arctic sea ice extent and thickness began to decline and loss of mass from the Greenland ice sheet accelerated only in the 1990s. Rapid changes in cryospheric components have occurred in this century, affecting snow cover, Arctic sea ice extent, the mass balance of the Greenland ice sheet, and frozen ground temperatures. Projections for this century, based on model results from the Intergovernmental Panel on Climate Change, involve dramatic changes by 2100. [ABSTRACT FROM AUTHOR]

Information about the state of the Arctic sea ice is becoming increasingly important. This paper describes an approach for automatic retrieval of daily thin sea ice thickness maps around Svalbard. The algorithm uses thermal satellite imagery from MODIS to estimate the surface temperature of the ice and further uses a thermal model of the ice surface to estimate the thickness of the sea ice. The approach is usable for thin sea ice, up to ca. 50 cm thick, during cold weather (freezing) conditions and without cloud cover present. The algorithm is compared with helicopter-borne electromagnetic ice thickness measurements. The comparison yields increasing root-mean-square deviation (RMSD) for thicker ice. The lowest RMSD found is 8.7 cm for ice thickness in the range 10 cm < hi ≤ 20 cm. The highest RMSD found is 25.2 cm for ice thickness in the range 30 cm < hi ≤ 40 cm. The bias shows no such trend, and the overall bias is found to be −5.5 cm. The results show that this is a promising approach, allowing monitoring of thin sea ice thickness at relatively higher spatial resolution. [ABSTRACT FROM AUTHOR]

The climate is changing and the people in the Arctic are facing huge challenges. Many rely on natural resources for both subsistence and income. Successful adaptation to climate change and the sustainable use of resources requires observation of the environment. Scientific knowledge of the environment is incomplete and conventional scientific monitoring is logistically difficult. Local fishers and hunters observe the environment all year-round. Their observations and knowledge are, however, not consistently quantified, analyzed, or used for resource management. We present a simple, field-based system for monitoring and managing resources developed specifically to enable Greenlandic fishers and hunters to document trends in living resources and to propose management decisions themselves. This system was designed to build upon existing informal observing methods, and there is interest in the system among rural fishers and hunters. We describe correspondence between community members’ perceptions and professional scientists’ assessments of the abundance of sea-ice, shipping, fish, mammals, and birds. Community-based documentation can pinpoint particular species and areas that are in need of attention. At the same time, it can help link observed environmental changes to management action. We hope this paper will encourage other stakeholders to develop their own local monitoring systems so as to facilitate adaptive management responses at both local and national levels. [ABSTRACT FROM PUBLISHER]

The decreasing of Arctic sea ice is projected to continue with global warming, which makes the summer navigation conditions of the Arctic improve. Based on the multi-source remote-sensing data with inter-sensor calibration processing and the ship-based observational data from R/V Xuelong and M/V Yongsheng, the sea ice conditions of the Arctic Northeast Passage (NEP) during the 2002–2021 summer seasons were analyzed, and the navigability of the NEP between July and October from 2002 to 2021 was discussed. Inter-sensor calibration could effectively reduce the deviation from different passive microwave data. Sea ice extent and thickness in the NEP decreased annually, which resulted in the navigability of the NEP showing a potential tendency toward improvement in navigability. The navigation period was mainly concentrated in early August to early October. The middle part of the NEP was primarily affected by sea ice. This influence decreased over time, while the navigation period increased, especially in the Vilkitsky Strait, which is a key shipping area. This analysis of sea ice conditions and navigability in the past 20 years could provide a reference for future scientific investigations and aid in merchant ship navigation in the Arctic summer. [ABSTRACT FROM AUTHOR]

Everyday life in the Arctic has become increasingly digitalized. The academic discussion around it focuses on three aspects: digital infrastructures and access; digital promises; and digitalization risks and challenges to human security. The existing critical research on e-governance in the Arctic has been done in the North American and European Arctic, while digital governance in the Russian Arctic has mostly remained beyond the scope of research. In this article, we aim to fill the gap by demonstrating how Russian Arctic infrastructural geography affects digital governance in the region. To achieve this goal, we used a mixed methods approach. First, to grasp the structural differences between Arctic and non-Arctic Russia, we analyzed open data from the Russian e-procurement system concerning the share of contracts with local suppliers, the percentage of terminated contracts, and indicators of contract time sensitivity. Second, to explore the mechanics of e-procurement in the Arctic, we gathered interviews with procurers working in state organizations in three remote settlements in different parts of the Russian Arctic: The Republic of Sakha (Yakutia), Krasnoyarsk Krai, and Arkhangelsk region. By combining these data, we produce a detailed picture of e-procurement across the differentiated Russian Arctic infrastructural geography. [ABSTRACT FROM AUTHOR]

The Arctic is often cast as a site where natural resources can be extracted with processes eased by retreating sea ice. This article argues that Arctic resource euphoria is misplaced – at least partly – due to the worsening climatic, ecological, and social crises that increase the costs and risks of extraction. Permafrost melt is making mineral and fossil fuel extraction riskier and more difficult, as extractive infrastructures – built with great sunk costs – are deteriorating. The climate catastrophe can already be observed, first-hand, in the Arctic. This can give insights into what kinds of dynamics can be expected globally. The deterioration of extractive infrastructures caused by the climate crisis is likely to dampen the forecasts for expanding extractivism. This article identifies interdisciplinary research gaps and needs, while offering new prognoses for the future in and through the Arctic at the interface of climate crises, global climate tipping points, and resource extraction. [ABSTRACT FROM AUTHOR]

Complex ecosystems characterize the Arctic Region, which experiences rapid environmental changes due to climate change. These changes are happening spatially as much as temporally. Spatiotemporal interactive three-dimensional visualization of environmental phenomena is eye-catching, while creating the foundations for the rapid understanding of Arctic complexity. The Arctic is a circumpolar region; cylinders seem suitable visual media for related data. In this case study, the visualization of anomalies of the sea ice illustrates abnormal changes, helping the viewer/user to focus on that filtered information rather than becoming lost in a multitude of information. A holistic view of dynamic environmental changes in a stand-alone visual could impact the quick understanding, response and policymaking regarding the visualized phenomena. [ABSTRACT FROM AUTHOR]

As global warming is causing a significant reduction in the extent and the thickness of Arctic sea ice, a narrative for future large-scale commercial shipping in the Arctic has started to evolve. However, while most efforts have aimed to assess the financial benefits along with potential savings in greenhouse gas emissions, few studies have explored risk patterns and safety issues associated with Arctic shipping and its current commercial alternatives in a geospatial manner. This study aims at addressing this gap in the literature, by assessing the risk factors associated with Arctic shipping, in particular, risks along the Northern Sea Route (NSR) connecting European and Asian ports. Its main component includes a global least-cost analysis, aiming to assess global and Arctic risk factors associated with commercial shipping, to derive the least risk paths from 10 major ports in Europe to 10 in Asia. To project the results into the future, and thus assess the future potential of the NSR as a viable and less risky alternative, a dataset on predicted sea ice thickness within 2010–2099, restricted the analysis based on the penetration capabilities of three selected vessel types. Ultimately, the study concludes that maritime transportation, bound for East-Asia, commencing from most northern European ports, could benefit from the NSR, not just in terms of distance savings, cost reduction and less CO2 production, but also as a safer alternative. Lastly, two recommendations drawn from our results aim to assist decision-makers in facilitating future Arctic transportation by addressing accessibility and safety issues. Highlights We explore risk patterns and safety issues associated with Arctic shipping and its current commercial alternatives in a geospatial manner. We assess the future potential of the northern sea route (NSR) as a viable and less risky alternative for European-Asian shipping. We provide a discussion on pros and cons of utilising the NSR in terms of distance savings resulting in cost reduction as well as less CO2 production, and as a safer alternative. [ABSTRACT FROM AUTHOR]

The potential of Arctic routes (ARs) has attracted global attention, and exploiting the Arctic has become an important strategy for many countries. However, there are still some challenges for ships sailing in Arctic ice zones, including harsh marine environments and the insufficient service capacity of sea ice information service systems. To better understand the route changes in the Arctic and extract real-time ship navigation routes, we developed an online interactive route planning system (RouteView) for ships sailing in the Arctic based on big Earth data. RouteView includes two main features: (1) an online calculation interface is provided for optimal routes along the Arctic Northeast Passage (NEP) 60 days into the future by utilizing reinforcement learning (RL) based on sea ice and meteorological data, and (2) an online ice-water classification is established based on synthetic aperture radar (SAR) data and deep learning to help users extract the sea ice distribution in real time. This work can potentially enhance the safety of shipping navigation along the NEP and improve information extraction methods for ARs. [ABSTRACT FROM AUTHOR]

According to the boundary conditions between two adjacent layers, a method for calculating the acoustic reflection coefficient of the layered ice-snow model is proposed, which is called the boundary condition method (BCM). Based on the actual ice parameters chosen from Schwarz and Weeks data, reflection coefficients under different conditions are analyzed. Comparing the BCM with the impedance transfer method (ITM), the results verified the validity of the BCM. After calculating and analyzing the multilayer ice-snow, it can be found that snow layer has more influence on the low-frequency sound waves. Snow layers have varying effects on the sound reflection coefficient depending on ice thickness: the thicker the ice layer is, the less influence the snow layer has on the sound reflection coefficient. The ice reflection coefficient model is combined with the Bellhop sound field simulation model, and the sound field simulation results are compared with the ninth Chinese polar scientific expedition results. [ABSTRACT FROM AUTHOR]

The Arctic is rapidly transforming into a navigable ocean because of global warming. Consequently, a large percentage of the sailing distance between Europe and Asia could be saved by alternatively sailing through the Arctic. However, taking Arctic routes is fraught with risks and additional costs due to sea ice. The major purpose of this study is to improve safety and fuel efficiency of Arctic ships, which is achieved by voyage optimization upon frequently updated meteorological, oceanographic and ice forecasting. The resistance model accounts for both ice thickness and ice concentration of unconsolidated Arctic sea ice in summer. Ice-induced risks defined in the Polar Operational Limit Assessment Risk Indexing System (POLARIS) are dealt as constraint. Other constraints such as avoidance of land and shallow water are also included. These functions are demonstrated by the two case study vessels sailing between Rotterdam and Shanghai via both the Arctic and the traditional routes. [ABSTRACT FROM AUTHOR]

The Devon Ice Cap (DIC) is one of the largest ice masses in the Canadian Arctic. Each summer, extensive supraglacial river networks develop on the DIC surface and route large volumes of meltwater from ice caps to the ocean. Mapping their extent and understanding their temporal evolution are important for validating runoff routing and melt volumes predicted by regional climate models (RCMs). We use 10 m Sentinel-2 images captured on 28 July and 10/11 August 2016 to map supraglacial rivers across the entire DIC (12,100 km2). Both dendritic and parallel supraglacial drainage patterns are found, with a total length of 44,941 km and a mean drainage density (Dd) of 3.71 km−1. As the melt season progresses, Dd increases and supraglacial rivers form at progressively higher elevations. There is a positive correlation between RCM-derived surface runoff and satellite-mapped Dd, suggesting that supraglacial drainage density is primarily controlled by surface runoff. [ABSTRACT FROM AUTHOR]

Improving situational awareness and crisis response are key priorities in reducing potential risks associated with sea ice and environmental-related hazards in the Arctic. This research explores the opportunities and challenges associated with leveraging arctic system science research to coproduce sea ice decision support tools. The research is based on information derived from a coastal radar operated as part of university research in Utqiaġvik, Alaska as well as decision context analysis from 12 interviews with marine operators and responders, subsistence users, and service providers. Findings revealed a diversity of information preferences and needs, decision thresholds, capacities, and constraints. A sea ice notification framework is presented, which illustrates how near-real time observations can be integrated into existing trusted notification systems. Key challenges to using Arctic system science research to support decision maker needs include the logistics of operating and maintaining near-real time observations. Innovative partnerships and informal networks may be especially important in overcoming these challenges. [ABSTRACT FROM AUTHOR]

Profound changes in Arctic sea-ice, a growing desire to utilize the Arctic's abundant natural resources, and the potential competitiveness of Arctic shipping routes, all provide for increased industry marine activity throughout the Arctic Ocean. This is anticipated to result in further challenges for maritime safety. Those operating in ice-infested waters require various types of information for sea-ice and iceberg hazards. Ice information requirements depend on regional needs and whether the stakeholder wants to avoid ice all together, operate near or in the Marginal Ice Zone, or areas within the ice pack. An insight into user needs demonstrates how multiple spatial and temporal resolutions for sea-ice information and forecasts are necessary to provide information to the marine operating community for safety, planning, and situational awareness. Although ship-operators depend on sea-ice information for tactical navigation, stakeholders working in route and capacity planning can benefit from climatological and long-range forecast information at lower spatial and temporal resolutions where the interest is focused on open-water season. The advent of the Polar Code has brought with it additional information requirements, and exposed gaps in capacity and knowledge. Thus, future satellite data sources should be at resolutions that support both tactical and planning activities. [ABSTRACT FROM AUTHOR]

The world's icy and snowy regions—the cryosphere—are where the most profound changes will occur as the globe continues warming. In many areas, the levels of cryospheric change today are surpassing any seen in the past hundreds to thousands of years. This amplified response has a simple explanation: Most of the cryosphere is, on average, near the freezing point. Small shifts in temperature push large regions to a different physical state. However, while the processes leading to the loss of ice are quickly started, they do not quickly stop. We are on the verge of committing ourselves to sizable increases in sea level. The 2007 Intergovernmental Panel on Climate Change (IPCC) report estimated sea level rise in this century at just 20 to 60 centimeters, but that total did not include contributions from the break-up and flow of ice sheets. The melting of mountain glaciers and ice in Greenland and Antarctica could add an additional meter of sea level rise. An equally important effect may be the feedback that changes in ice—especially the ice-covered ocean—have on climate in both the polar and the temperate regions of the world. The author describes the processes that are rapidly eroding polar ice. [ABSTRACT FROM AUTHOR]

Fluctuations in arctic sea ice are perhaps the most vivid signs of a warming global climate, yet relatively little is known about sea ice dynamics. A leading sea ice researcher unpacks the mysteries behind climate change's leading edge. [ABSTRACT FROM AUTHOR]

Mapping of sea ice in the Arctic region is essential for environmental monitoring and ship navigation. Synthetic Aperture Radar can be used to observe sea ice at high spatial and temporal resolutions over an extended range at high latitudes. The sea ice discrimination method based on Support Vector Machine was applied to 226 scenes of Sentinel-1 acquired in Extra Wide Swath Mode with dual-polarization (HH & HV) from 1 July 2016 to 31 August 2016 along the Northern Sea Route from the Kara Sea to the Chukchi Sea. The discriminated sea ice results were evaluated using both manually classified ice maps and Multisensor Analyzed Sea Ice Extent (MASIE). It is revealed that the proposed method based on the backscattering coefficient (σ0), incidence angle, air temperature, and wind speed improves the sea ice and water discrimination, showing matching rates of approximately 93.4% for manual classification and 82.8% for MASIE. It is concluded that the method could be considered for an operational use to discriminate summer sea ice from open water in the Northern Sea Route. [ABSTRACT FROM AUTHOR]

A new seasonal and annual dataset describing Arctic sea ice extents for 1901–2015 was constructed by individually re-calibrating sea ice data sources from the three Arctic regions (North American, Nordic and Siberian) using the corresponding surface air temperature trends for the pre-satellite era (1901–1978), so that the strong relationship between seasonal sea ice extent and surface air temperature observed for the satellite era (1979-present) also applies to the pre-satellite era. According to this new dataset, the recent period of Arctic sea ice retreat since the 1970s followed a period of sea ice growth after the mid-1940s, which in turn followed a period of sea ice retreat after the 1910s. Arctic sea ice is a key component of the Arctic hydrological cycle, through both its freshwater storage role and its influence on oceanic and atmospheric circulation. Therefore, these new insights have significance for our understanding of Arctic hydrology.EDITOR D. KoutsoyiannisASSOCIATE EDITOR not assigned [ABSTRACT FROM PUBLISHER]

Arctic sea ice data from a variety of historical sources have been synthesized into a database extending back to 1850 with monthly time-resolution. The synthesis procedure includes interpolation to a uniform grid and an analog-based estimation of ice concentrations in areas of no data. The consolidated database shows that there is no precedent as far back as 1850 for the 21st century's minimum ice extent of sea ice on the pan-Arctic scale. A regional-scale exception to this statement is the Bering Sea. The rate of retreat since the 1990s is also unprecedented and especially large in the Beaufort and Chukchi Seas. Decadal and multidecadal variations have occurred in some regions, but their magnitudes are smaller than that of the recent ice loss. Interannual variability is prominent in all regions and will pose a challenge to sea ice prediction efforts. [ABSTRACT FROM AUTHOR]

The article discusses the impact of sea ice melting in the Arctic on the entire global environment and the tensions existing between expanding Arctic oil operations and reducing future threats of climate change. It cites calls from Nobel Women laureates to protect the Arctic Ocean and the Earth's global climate by ending future oil and gas operations as they called attention to serous risks of offshore drilling in remote and sensitive resources necessary to indigenous communities and wildlife.

With the rapidly melting sea ice in the Arctic, and developing shipping traffic, emerged the idea, popular with the media, that sea ice would soon be completely dominated by first-year ice, and would thus be comparable to ice present in the Gulf of St. Lawrence: this would allow for the setting up of shipping year-round along Arctic passages. In fact, contrary to this idea, even with the vanishing of multi-year ice, ice conditions will remain very different in the Arctic from ice prevailing in the Gulf. Besides, naval technology certainly helps overcoming challenges of ice navigation, but they do not mean it is economically or technically much easier. Year-round shipping in the Arctic remains a difficult challenge to overcome. [ABSTRACT FROM PUBLISHER]

This manuscript presents an evaluation of global climate models to guide future projections of Arctic sea ice extent (SIE). Thirty-five model simulations from Coupled Model Intercomparison Project, Phase 5 were examined to select model subsets using comparison to observational data (1979–2013). The study extends previous work by highlighting the seasonality of sea ice trends, utilizing a multi-step selection process to demonstrate how the timing of an ice-free Arctic varies with the hindcast performance of the models, and extending the analysis to include sudden ice loss events (SILE). Although the models' trends for the historical period are generally smaller than observed, the models' projected trends show a similar seasonality, largest in September and smallest in March to April. A multi-step evaluation process is applied to obtain progressively smaller subsets of the best-performing models. As the number of models retained becomes smaller, the simulated historical trend becomes larger and the median date of a projected ice-free Arctic becomes earlier. An examination of SILE through the historical period and model projections from 2014 through 2099 shows that SILE can account for between half and all of the future net loss of SIE. We created an application for exploring sea ice data:http://spark.rstudio.com/uafsnap/sea_ice_coverage/. [ABSTRACT FROM PUBLISHER]

In order to assess whether the Arctic region is evolving into a region of cooperation or one of confrontation, a thorough understanding of the existing (and evolving) bilateral, regional and international institutional frameworks with relevant regulations for the Arctic and their adequacy for solving possible controversies is paramount. Disputes can flare up over various issues, as the Arctic has aptly demonstrated in recent years. Whether these disputes erupt into conflict or are handled cooperatively depends significantly on the rules and regulations that parties have put in place. While most of the literature deals with resource ownership, it is argued here that the more significant potential sources of controversy between Arctic states are issues of responsibility, liability, precaution and preparedness concerning possible transboundary environmental risks and dangers and, generally, protection of the fragile Arctic ecosystem. [ABSTRACT FROM PUBLISHER]

Indigenous sea ice experts from three Alaskan communities, geophysicists, an anthropologist, and information technology specialists collaborated to develop an observational framework and a database to record, archive, disseminate, and analyze sea ice observations. Observations are based on ice uses and information about ice conditions, weather, ocean state, and animal behavior relevant to hunters and to community members. Daily logs kept during the ice season have been archived since 2006, with key variables extracted for subcategories pertaining to weather and ice observations, ice-related activities, and wildlife. The observation program and the development of the associated database are discussed in terms of community wishes and information needs and the potential uses for hunters, students, and others in coastal Alaska. Database records for Gambell, Wales, and Barrow, Alaska, are analyzed to arrive at a representative seasonal cycle of ice conditions for 2006/2007. This single year is placed into a longer-term context by examining interannual variability for freeze-up and breakup dates from 2006 through 2011 extracted from the database. We discuss the adaptive nature of the database framework and its relevance to coastal communities in gathering and transmitting knowledge about the ice environment that can help in adapting to rapid Arctic change. [ABSTRACT FROM PUBLISHER]

The Arctic is opening. Global warming is leading to seasonal sea-ice retreat, which in turn opens hitherto impassable shipping routes and new areas for resource exploitation. Such changes are elevating the Arctic's geostrategic value and stoking inter-state competition. The admission of five Asian states as Arctic Council observers in 2013 underlines the increased importance of the High North in global politics. And as the sea ice retreats, so military forces are redeployed northwards, raising the prospect of conflict. Christian Le Mière and Jeffrey Mazo bring much-needed sobriety to the discussion of change in the Arctic, outlining the possibilities of and limits to economic opportunities in the High North while providing a detailed examination of the political and military changes this might bring. Their analysis provides an invaluable guide as the region transforms from a parochial concern to a global interest. [ABSTRACT FROM AUTHOR]

A grant maker provides insight into how philanthropy can work with Arctic communities experiencing rapid change from the simultaneous impacts of climate change and globalization in the North Pacific. The focus is on the role that philanthropy can play in assisting communities in coping with changing sea ice conditions by recognizing that communities are an integral part of the social-ecological system. The role of resilience and how philanthropic organizations can increase resilience in Arctic communities and build upon their own initiatives is examined. Though private philanthropic investments are small relative to all funding in the north, they have the advantage of being nimble and are able to experiment with new ideas and novel approaches, though these efforts are not without their challenges. [ABSTRACT FROM AUTHOR]

The treatment of sea ice in USA and Canadian law has failed adequately to allocate and manage demands on Arctic sea ice among competing uses. Decision makers have generally categorized sea ice as either land or water, a binary approach that ignores its unique characteristics and the services it provides to many different users. Agency action and related litigation in the USA demonstrate sea ice user conflicts and highlight the tendency of US law to protect only one type of user at a time. In Canada, two recent Inuit Land Claims Agreement create zones that encompass sea ice. Yet both systems are beginning to acknowledge sea ice as a component of larger systems and as a resource with multiple uses and users. Both countries have the seeds of mechanisms in place to allow multiple users of sea ice to provide input on planning decisions affecting sea ice. While much work lies ahead, and none of these steps on its own clarifies the legal status of sea ice, combined they provide a modest foundation for beginning to better balance competing uses of sea ice in a warming Arctic. [ABSTRACT FROM AUTHOR]

Shorefast ice, present along Alaska's Arctic coastline from late fall through early summer, provides a platform for subsistence hunting by coastal indigenous communities. At Barrow, Alaska, Iñupiat hunters build trails each spring across the shorefast ice to connect the community to the adjacent lead where they hunt migrating bowhead whales. Building on efforts initiated by Alaska's North Slope Borough and in collaboration with the Barrow Whaling Captains Association, a systematic ice trail mapping and surveying project was developed in spring 2008. Using electromagnetic induction sounding, ice thickness surveys were completed along trails just prior to whaling. Semi-directed interviews with hunters addressed the impact of ice conditions on the hunt, choice of trail and hunting locations, and safety concerns. Four years of results (2008–2011) have shown that (1) tracking of local ice conditions along ice trails reveals the interannual variability of the shorefast ice thickness distribution, (2) documenting trail building and hunting strategies provides a baseline for how the community copes with variability, and (3) developing information resources for the community facilitates interaction with hunters and maintains project relevance to environmental challenges facing the community. [ABSTRACT FROM AUTHOR]

The sea ice cover decreases and human activity increases in Arctic waters. Fisheries and bycatch issues, shipping and petroleum exploitation (pollution issues) make it imperative to establish biological baselines for the marine fishes inhabiting the Arctic Ocean and adjacent seas (AOAS). Species richness, zoogeographic affiliations and Red List statuses among chondrichthyan fishes (Chondrichthyes) were examined across 16 AOAS regions as a first step towards credible conservation actions. Published literature and museum vouchers were consulted for presence/absence data. Although many regions are poorly sampled, 49 chondrichthyan species have been reported from the AOAS. Skates and rays are the most species-rich taxon, represented by 27 species in family Rajidae and one species in family Dasyatidae. The sharks comprise 20 species in 13 families and the chimaeras one species in family Chimaeridae. The Norwegian Sea (28), Barents Sea (19) and Bering Sea (18) are particularly species-rich, and despite similar species numbers the two latter seas have no species in common. The remaining AOAS regions are inhabited by six species or less. Large-scale commercial fisheries for chondrichthyans are yet to be developed in the AOAS, but the precautionary principle should be implemented as abundances, basic taxonomy and biology are still largely unknown. [ABSTRACT FROM AUTHOR]

The dispersal abilities of terrestrial mammals are severely constrained by water crossings, resulting in islands generally supporting less diverse mammal faunas than similar continental areas. In ice-affected Arctic regions, seasonal or permanent ice cover provides a bridging mechanism for dispersal, allowing water gaps to be crossed more rapidly and with less energy cost than is entailed in swimming. Consequently, islands that might be out of reach if waters were open become much more readily colonised in the presence of ice. We reviewed the distribution of terrestrial mammals on selected islands throughout the Arctic and analyse historical data for several sites in the Canadian Arctic where mammal populations have undergone extirpation and re-colonisation. We use these data to assess the value of ice for the dispersal of Arctic terrestrial mammals. Given observed dispersal distances we estimate the likely impact of future ice reduction on island faunas. We predict that, as ice cover duration shortens, immigration will decline leading to increased extinctions of island populations and potentially, in the long-term, local genetic differentiation. The eventual disappearance of ice bridges, preventing the immigration of southern species, may leave certain arctic archipelagos as the last refuge for typical Arctic mammals. [ABSTRACT FROM AUTHOR]

Arctic sea ice undergoes a very strong annual cycle. This study sets out to look at the transition when the Arctic sea ice starts to melt using satellite-obtained passive microwave brightness temperatures and satellite-derived albedo data for 13 points within the Arctic, including both first-year and multiyear ice locations, for 1995–2000. Special sensor microwave imager (SSM/I) brightness temperature differences are used to determine melt onset dates once surface temperatures approach freezing. Independently, satellite-derived albedo data are obtained and a melt onset date is derived. Generally, the two methods produce the same date for melt onset with optimum conditions. However, in most cases there are clouds present, which for the albedo data restrict observations and generate melt dates that are several days later than the passive microwave melt onset which is not affected by cloud cover. Melt onset dates, determined from the passive microwave brightness temperatures, are compared to those from the albedo observation to determine differences between the two methods. For first-year ice (FYI) locations, the average differences in melt onset dates for the study locations between the passive microwave and albedo-derived methods are +/−3 days. The average difference for multiyear ice (MYI) locations melt onset dates is around 8 days, slightly longer than the (FYI) locations, however, this is due to more cloudy conditions. The results indicate that the passive microwave-derived melt onset dates and albedo-derived dates are very close and either method could be used to determine melt. The advantage of using microwave data would be the independence of having to have cloud free conditions. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

Climate change has reduced the extent and thickness of sea ice in the Arctic, making international shipping in the Northwest Passage a virtual certainty in the foreseeable future. Such future shipping raises the question of whether the Passage is or might become an international strait, with the consequent right of transit passage. This article examines the two possible legal bases for Canada's claim that the waters of the Canadian Arctic Archipelago are internal waters: a historic title and straight baselines. It also addresses the issue of the possible internationalization of the Passage, if Canada does not take preventive measures. Some such measures are recommended in the last part of the article. [ABSTRACT FROM AUTHOR]

Angular distributions of spectral reflectance for four common arctic surfaces: snow-covered sea ice, melt-season sea ice, snow-covered tundra, and tundra shortly after snowmelt were measured using an aircraft-based, high angular resolution (1°) multispectral radiometer. Results indicate bidirectional reflectance is higher for snow-covered sea ice than melt-season sea ice at all wavelengths between 0.47 and 2.3 μm, with the difference increasing with wavelength. Bidirectional reflectance of snow-covered tundra is higher than for snow-free tundra for measurements less than 1.64 μm, with the difference decreasing with wavelength. Bidirectional reflectance patterns of all measured surfaces show significant reflectance maxima in the forward scattering direction of the principal plane with identifiable specular reflection for the melt-season sea ice and snow-free tundra cases. The snow-free tundra had the most significant backscatter (similar to other vegetative bidirectional reflectance patterns such as for Cerrado in Brazil), and the melt-season sea ice the least. For sea ice, bidirectional reflectance changes due to snowmelt were more significant than differences among the different types of melt-season sea ice. The spectral-hemispherical (plane) albedo of each measured arctic surface was also computed. Comparing measured nadir reflectance to albedo for sea ice and snow-covered tundra shows nadir reflectance 5-40% smaller, with the largest difference at wavelengths beyond 1 μm. For snow-free tundra, nadir reflectance is 30-50% smaller than the plane albedo. [ABSTRACT FROM AUTHOR]