The Arctic is undergoing rapid climate change and is projected to experience the most warming this century of any world region. We review the societal aspects of these current and projected changes. Indigenous knowledge and local knowledge holders living in communities across the Arctic have detected unprecedented increases in temperature, altered precipitation regimes, and changing weather patterns, documenting impacts on terrestrial and marine environments. These local observations situate climate change as one of multiple interacting stressors. Arctic societies have exhibited resilience to climate change, but vulnerabilities are emerging at the nexus of changing environmental conditions and socioeconomic pressures. Infrastructure is highly susceptible to permafrost thaw, coastal erosion, and sea level rise, compounded by the age of infrastructure, maintenance challenges, and cost of adapting. Livelihoods and cultural activities linked to subsistence harvesting have been affected by changes to wildlife, with coping mechanisms undermined by long‐term processes of land dispossession and landscape fragmentation. Reduced sea ice coverage and changing ice dynamics are creating opportunities for enhanced shipping, oil and gas production, and deep‐water fisheries. Legal, infrastructural, economic, and climatic challenges are expected to constrain such developments, with concerns over the distribution of potential benefits. Adaptation is already taking place in some sectors and regions, with efforts directly targeting climate impacts and also addressing underlying determinants of vulnerability. Barriers and limits to adapting are evident. Research that develops projections of future climate impacts is advancing, but studies examining the implications of such changes for communities or economies remain in their infancy.

随着北极战略价值的提升,北极旅游热不断升温,北极旅游发展影响因素研究理应得到重视。本文检索了科学引文索引（Web of Science）和中国知网（CNKI）中北极旅游研究的相关文献,借助CiteSpace文献计量分析软件的关键词共现分析和时区视图分析等功能,分析了北极旅游的研究热点及其演化过程,系统综述了北极旅游影响因素的研究进展。研究表明：①北极旅游研究还未成规模。相对来说,国外起步较早,研究涵盖面较广,积累了比较丰富的经验;而国内起步较晚,仅从气候变化与地缘政治等方面进行探讨,广度和深度不足。已有研究中涉及影响因素的多从目的地角度开展分析,经济水平、游客构成等客源市场方面还有待加强。②前10位北极旅游研究热点中,气候变化、治理、人为干扰、海冰、脆弱性、恢复力、旅游管理等都与北极旅游影响因素密切相关。③已有研究中北极旅游影响因素可以归纳为政治政策、气候变化、旅游资源、旅游气候舒适度和管理与基础设施5类。其中,政治稳定和气候变化是北极旅游发展的前提许可和宏观影响因素。前者是北极旅游能否开展的最基本也是最关键因素,后者则是北极旅游能否发展的重要影响因素,既能直接影响旅游资源,又能通过对天气的影响,进而影响游客行为。而旅游资源、旅游气候舒适度和管理与基础设施则是北极旅游可持续发展的直接影响因素。

With the improvement of the strategic value of the Arctic and Arctic tourism continues to become more popular, there are increasingly more publications related to Arctic tourism. At the same time, an increasing number of scholars pay more attention to the influencing factors of the development of Arctic tourism. Using the literature analysis method and CiteSpace software, this study analyzed the research progress of the influencing factors of Arctic tourism development in detail based on the relevant literature of Arctic tourism in China and internationally. This study shows that: (1) In China, there are few studies examining the influencing factors of the development of Arctic tourism at present. Related literature in China mainly discussed the influencing factors of Arctic tourism development in terms of climate change and geopolitics. International Arctic tourism research started earlier and the content is more comprehensive. In addition to the studies of climate change and geopolitical pattern, the impact of different stakeholders, weather conditions, and management on Arctic tourism development have also been actively discussed in the international literature. (2) Climate change, governance, human disturbance, sea ice, vulnerability, resilience and management are all closely related to the influencing factors of Arctic tourism. (3) The influencing factors of Arctic tourism in existing studies can be classified into five categories: politics and policy, climate change, tourism resources, tourism climate comfort, and management and infrastructure. Political stability and climate change are the prerequisite and macro influencing factors for the development of Arctic tourism, while tourism resources, tourism climate comfort, and management and infrastructure are the factors directly affecting the sustainable development of Arctic tourism.

This paper assesses the value and environmental feasibility of Arctic shipping by reviewing the relevant scientific and economic peer‐reviewed literature. From the physical perspective, this paper examines the impact of climate change on sea ice and marine weather and considers the resultant consequences for Arctic shipping accessibility. From an economic perspective, it reviews the major research investigating the economic feasibility of diverting ships from conventional shipping routes to Arctic routes, the attitudes of shipping stakeholders, and other major factors affecting the prospect of Arctic shipping. This review also identifies important research gaps. Ultimately, we find that the complex environmental and economic dynamics of the Arctic suggest that an appropriate understanding of Arctic shipping will require close collaboration between natural and social scientists.

Amplified climate warming has led to permafrost degradation and a shortening of the winter season, both impacting cost-effective overland travel across the Arctic. Here we use, for the first time, four state-of-the-art Land Surface Models that explicitly consider ground freezing states, forced by a subset of bias-adjusted CMIP5 General Circulation Models to estimate the impact of different global warming scenarios (RCP2.6, 6.0, 8.5) on two modes of winter travel: overland travel days (OTDs) and ice road construction days (IRCDs). We show that OTDs decrease by on average −13% in the near future (2021–2050) and between −15% (RCP2.6) and −40% (RCP8.5) in the far future (2070–2099) compared to the reference period (1971–2000) when 173 d yr−1 are simulated across the Pan-Arctic. Regionally, we identified Eastern Siberia (Sakha (Yakutia), Khabarovsk Krai, Magadan Oblast) to be most resilient to climate change, while Alaska (USA), the Northwestern Russian regions (Yamalo, Arkhangelsk Oblast, Nenets, Komi, Khanty-Mansiy), Northern Europe and Chukotka are highly vulnerable. The change in OTDs is most pronounced during the shoulder season, particularly in autumn. The IRCDs reduce on average twice as much as the OTDs under all climate scenarios resulting in shorter operational duration. The results of the low-end global warming scenario (RCP2.6) emphasize that stringent climate mitigation policies have the potential to reduce the impact of climate change on winter mobility in the second half of the 21st century. Nevertheless, even under RCP2.6, our results suggest substantially reduced winter overland travel implying a severe threat to livelihoods of remote communities and increasing costs for resource exploration and transport across the Arctic.

Degradation of near-surface permafrost can pose a serious threat to the utilization of natural resources, and to the sustainable development of Arctic communities. Here we identify at unprecedentedly high spatial resolution infrastructure hazard areas in the Northern Hemisphere's permafrost regions under projected climatic changes and quantify fundamental engineering structures at risk by 2050. We show that nearly four million people and 70% of current infrastructure in the permafrost domain are in areas with high potential for thaw of near-surface permafrost. Our results demonstrate that one-third of pan-Arctic infrastructure and 45% of the hydrocarbon extraction fields in the Russian Arctic are in regions where thaw-related ground instability can cause severe damage to the built environment. Alarmingly, these figures are not reduced substantially even if the climate change targets of the Paris Agreement are reached.

Transportation in the Pan-Arctic winter is highly dependent on ice roads, which are affected by surface air temperatures and snow cover. In the context of polar increased warming, there is an urgent need to quantify the uncertainties of ice roads and their contribution to terrestrial transport. We evaluated the spatiotemporal characteristics of potential ice road changes by calculating four indicators: potential ice road area (PIRA), potential ice road days (PIRDs), potential ice road onset date (PIROD), and potential ice road end date (PIRED) from October to May, 1979–2017. Taking port accessibility as an example, we constructed a port accessibility model to quantify the contribution of potential ice roads to terrestrial transport. All four indicators showed significant (p < 0.05) reductions in potential ice roads. PIRA experienced the largest share of losses in May (∼25%) and the sharpest reductions in April (2.77 × 104 km2 yr−1). PIRDs were shortened by an average of 0.41 d yr−1, and delayed PIROD (0.28 d yr−1 on average) was more severe than advanced PIRED (0.21 d yr−1 on average). A stability analysis showed that potential ice roads were changing from suitable to unsuitable during November to May. Between December and April, potential ice roads can increase port accessibility by more than 24 h in Canadian Arctic and Siberia and by more than 9 h in Alaska. However, the contribution of potential ice roads has reduced over the past decades, especially in Nunavut. The results provide insights into changes in potential ice roads in the Pan-Arctic and suggest that remote land accessibility has decreased significantly with warmer winters.

Climate change is already being experienced in the Arctic with implications for ecosystems and the communities that depend on them. This paper argues that an assessment of community vulnerability to climate change requires knowledge of past experience with climate conditions, responses to climatic variations, future climate change projections, and non-climate factors that influence people's susceptibility and adaptive capacity. The paper documents and describes exposure sensitivities to climate change experienced in the community of Ulukhaktok, Northwest Territories and the adaptive strategies employed. It is based on collaborative research involving semi-structured interviews, secondary sources of information, and participant observations. In the context of subsistence hunting, changes in temperature, seasonal patterns (for example timing and nature of the spring melt), sea ice and wind dynamics, and weather variability have affected the health and availability of some species of wildlife important for subsistence and have exacerbated risks associated with hunting and travel. Inuit in Ulukhaktok are coping with these changes by taking extra precautions when travelling, shifting modes of transportation, travel routes and hunting areas to deal with changing trail conditions, switching species harvested, and supplementing their diet with store bought foods. Limited access to capital resources, changing levels of traditional knowledge and land skills, and substance abuse were identified as key constraints to adaptation. The research demonstrates the need to consider the perspectives and experiences of local people for climate change research to have practical relevance to Arctic communities such as for the development and promotion of adaptive strategies.

Shipping volumes in the Northwest Passage are likely to increase under climate change due to the distance advantage over traditional routes and the special strategic location of the Arctic. However, the harsh environment and poor channel conditions may pose a considerable risk to ship navigation. To ensure the safety of ships, understand the navigability of the route, and plan the sustainable use of the Northwest Passage, it is crucial to provide a quantitative risk assessment. Here, we present an analysis of several natural risks faced by ships in the Northwest Passage based on available datasets and use climate model simulations to project the navigability changes. The results showed that: (1) The sea-ice risk to ships in the Northwest Passage has been significantly reduced over the period 1979–2019, and the risk for Polar Class 6 (PC6) ships has decreased more rapidly than for general open-water (OW) ships. The difference in ice-breaking capacity further affects the seaworthy season, with the second seaworthy month being August for OW ships and October for PC6 ships, in addition to the commonly best September. (2) Low visibility is a more common form of adverse weather than strong wind for navigation in the Northwest Passage, mainly on the northern route, although pilotage conditions appear to be improving in September. (3) According to the comprehensive risk map, the distribution of risk is dominated by sea ice. The southern route of the Northwest Passage is superior to the northern route in terms of both sea ice and weather conditions, but there is a risk of shallow water. (4) For the northern route, which has greater transport potential, projections suggest that the sea-ice risk will be steadily lower than any extreme light ice year observed historically whether for the ship class OW or PC6 by 2050, with an increase of 50–80 navigable days, and the navigable period could be from June to January of the following year for PC6 ships by 2100. Our results provide valuable information for ships planning to pass through the Northwest Passage.

Unmanned Aerial Vehicle (UAV) systems, sensors, and photogrammetric processing techniques have enabled timely and highly detailed three-dimensional surface reconstructions at a scale that bridges the gap between conventional remote-sensing and field-scale observations. In this work 29 rotary and fixed-wing UAV surveys were conducted during multiple field campaigns, totaling 47 flights and over 14.3 km2, to document permafrost thaw subsidence impacts on or close to road infrastructure in the Northwest Territories, Canada. This paper provides four case studies: (1) terrain models and orthomosaic time series revealed the morphology and daily to annual dynamics of thaw-driven mass wasting phenomenon (retrogressive thaw slumps; RTS). Scar zone cut volume estimates ranged between 3.2 × 103 and 5.9 × 106 m3. The annual net erosion of RTS surveyed ranged between 0.35 × 103 and 0.39 × 106 m3. The largest RTS produced a long debris tongue with an estimated volume of 1.9 × 106 m3. Downslope transport of scar zone and embankment fill materials was visualized using flow vectors, while thermal imaging revealed areas of exposed ground ice and mobile lobes of saturated, thawed materials. (2) Stratigraphic models were developed for RTS headwalls, delineating ground-ice bodies and stratigraphic unconformities. (3) In poorly drained areas along road embankments, UAV surveys detected seasonal terrain uplift and settlement of up to 0.5 m (>1700 m2 in extent) as a result of injection ice development. (4) Time series of terrain models highlighted the thaw-driven evolution of a borrow pit (6.4 × 105 m3 cut volume) constructed in permafrost terrain, whereby fluvial and thaw-driven sediment transfer (1.1 and 3.9 × 103 m3 a−1 respectively) was observed and whereby annual slope profile reconfiguration was monitored to gain management insights concerning site stabilization. Elevation model vertical accuracies were also assessed as part of the case studies and ranged between 0.02 and 0.13 m Root Mean Square Error, whereby photogrammetric models processed with Post-processed Kinematic image solutions achieved similar accuracies without ground control points over much larger and complex areas than previously reported. The high resolution of UAV surveys, and the capacity to derive quantitative time series provides novel insights into permafrost processes that are otherwise challenging to study. The timely emergence of these tools bridges field-based research and applied studies with broad-scale remote-sensing approaches during a period when climate change is transforming permafrost environments.

Three model scenarios of changes in road infrastructure sustainability under permafrost thawing and degradation due to global climate change in nine Russian Arctic regions are considered. Until the current mid-century, economic assessment of the aftermath of climate change in these regions was physicogeographically based on six model climate assessments of cryogenic conditions, reflecting the most negative (scenario RCP8.5) option of the IPCC global climate change forecasts, which best fits the conditions of the Russian Arctic. The data of Russia's Transport Strategy until 2035, updated by the authors, serve as the basis for predicting road infrastructure development. An inertial (conservative) scenario of road infrastructure development in 2020-2050 shows that capital costs to maintain road infrastructure sustainability and reduce damage risks under permafrost thawing and degradation will average at least & x20bd;14 bln a year and will exceed & x20bd;21 bln and & x20bd;28 bln, respectively, under the moderate and modernization scenarios. The maximum indicators will be relevant for the Republic of Sakha (Yakutia), Magadan oblast, and the Chukotka Autonomous Okrug. The implementation of the modernization scenario will require revision of the existing standards, technologies, and entire economy of the road infrastructure and capital construction favoring the development of innovative standards and construction technologies, as well as the improvement of the proposed methodology and methods of cost estimation for these purposes.

. The retreat of sea ice has been found to be very\nsignificant in the Arctic under global warming. It is projected to continue\nand will have great impacts on navigation. Perspectives on the changes in\nsea ice and navigability are crucial to the circulation pattern and future\nof the Arctic. In this investigation, the decadal changes in sea ice\nparameters were evaluated by the multi-model from the Coupled Model\nInter-comparison Project Phase 6, and Arctic navigability was assessed under\ntwo shared socioeconomic pathways (SSPs) and two vessel classes with the\nArctic transportation accessibility model. The sea ice extent shows a high\npossibility of decreasing along SSP5-8.5 under current emissions and climate\nchange. The decadal rate of decreasing sea ice extent will increase in March\nbut decrease in September until 2060, when the oldest ice will have\ncompletely disappeared and the sea ice will reach an irreversible tipping\npoint. Sea ice thickness is expected to decrease and transit in certain\nparts, declining by −0.22 m per decade after September 2060. Both the sea\nice concentration and volume will thoroughly decline at decreasing decadal\nrates, with a greater decrease in volume in March than in September. Open\nwater ships will be able to cross the Northern Sea Route and Northwest Passage\nbetween August and October during the period from 2045 to 2055, with a maximum\nnavigable percentage in September. The time for Polar Class 6 (PC6) ships\nwill shift to October–December during the period from 2021 to 2030, with a\nmaximum navigable percentage in October. In addition, the central passage\nwill be open for PC6 ships between September and October during 2021–2030.\n

Weather can influence travel demand, traffic flow, and traffic safety. A hypothesis—the type of weather determined the likelihood of a change in travel behavior, and changes in travel behavior because of weather conditions depended on trip purpose—was assayed. A stated adaptation study was conducted in Flanders (the Dutch-speaking region of Belgium). A survey, completed by 586 respondents, was administered both on the Internet and as a traditional paper-and-pencil questionnaire. To ensure optimal correspondence between the survey sample composition and the Flemish population, observations in the sample were weighted. To test the main hypotheses, Pearson chi-square independence tests were performed. Results from both the descriptive analysis and the independence tests confirm that the type of weather matters and that changes in travel behavior in response to these weather conditions are highly dependent on trip purpose. This dependence of behavioral adjustments on trip purpose provides policy makers with a deeper understanding of how weather conditions affect traffic. Further generalizations of the findings are possible by shifting the scope toward revealed travel behavior. Triangulation of both stated and revealed travel behavior on the one hand and traffic intensities on the other hand is a key challenge for further research.

. Using thresholds of physical climate variables developed from community observations, together with two large-scale datasets, we have produced local indices directly relevant to the impacts of a reduced sea ice cover on Alaska coastal communities. The indices include the number of false freeze-ups defined by transient exceedances of ice concentration prior to a corresponding exceedance that persists, false break-ups, timing of freeze-up and break-up, length of the open water duration, number of days when the winds preclude hunting via boat (wind speed threshold exceedances), the number of wind events conducive to geomorphological work or damage to infrastructure from ocean waves, and the number of these wind events with on- and along-shore components promoting water setup along the coastline. We demonstrate how community observations can inform use of large-scale datasets to derive these locally relevant indices. The two primary large-scale datasets are the Historical Sea Ice Atlas for Alaska and the atmospheric output from a regional climate model used to downscale the ERA-Interim atmospheric reanalysis. We illustrate the variability and trends of these indices by application to the rural Alaska communities of Kotzebue, Shishmaref, and Utqiaġvik (previously Barrow), although the same procedure and metrics can be applied to other coastal communities. Over the 1979–2014 time period, there has been a marked increase in the number of combined false freeze-ups and false break-ups as well as the number of days too windy for hunting via boat for all three communities, especially Utqiaġvik. At Utqiaġvik, there has been an approximate tripling of the number of wind events conducive to coastline erosion from 1979 to 2014. We have also found a delay in freeze-up and earlier break-up, leading to a lengthened open water period for all of the communities examined.\n

Climate change vulnerability research methods are often divergent, drawing from siloed biophysical risk approaches or social-contextual frameworks, lacking methods for integrative approaches. This substantial gap has been noted by scientists, policymakers and communities, inhibiting decision-makers' capacity to implement adaptation policies responsive to both physical risks and social sensitivities. Aiming to contribute to the growing literature on integrated vulnerability approaches, we conceptualize and translate new integrative theoretical insights of vulnerability research to a scalable quantitative method. Piloted through a climate change vulnerability index for aviation and marine sectors in the Canadian Arctic, this study demonstrates an avenue of applying vulnerability concepts to assess both biophysical and social components analyzing future changes with linked RCP climate projections. The iterative process we outline is transferable and adaptable across the circumpolar north, as well as other global regions and shows that transportation vulnerability varies across Inuit regions depending on modeled hazards and transportation infrastructures.

This paper explores the relationship between sea ice conditions and cruise tourism activities in the Arctic Archipelago of Svalbard. It analyzes how cruise tourism planning and organization depend on sea ice conditions and to what extent Arctic climate change influences tourism. A mixed-method approach, including sea ice analysis and interviews with 13 cruise tourism stakeholders, was applied to grasp the complexity of Svalbard's cruise tourism. The outcomes show that cruise traffic depends on the sea ice cover, but only to some extent. Other factors, such as a location's attractiveness or sailing regulations also influence cruise itineraries around Svalbard. Sea ice conditions are in general considered favorable for cruising around Svalbard, and sea ice is a not a decisive factor in cruise planning and organization. The sea ice cover around Svalbard is decreasing; thus, high annual and inter-annual unpredictability of sea ice poses challenges for cruise operations around Svalbard. Flexibility in itineraries, plus good cooperation and management help the cruise industry adjust to any challenges arising from uncertain sea ice conditions. However, issues of overcrowding and decreased attractiveness due to disappearing ice are more and more visible and may challenge the development of cruise tourism around Svalbard in the future.

Climate change is strongly impacting the Arctic environment, leading to rapid sea ice loss. In some sectors, the retreating ice edge is perceived as an opportunity to expand and develop economic activities. Previous studies show this development in the Canadian and Russian Arctic. This paper examines mobility patterns of cruise ships and fishing vessels around Svalbard, a major hotspot of maritime activity and retreating sea ice cover, in relation to sea ice variability between August 2012 and September 2019. The results show a slight overall increase in fisheries and cruise activity, as well as remarkable trends of stretching operational seasons and expanding navigational areas in these sectors. Overall increasing activity and changing mobility patterns provoke a discussion about the implications for safe navigation and sustainable management, thus raising issues of high pan-Arctic relevance.

The topic investigated is the social-ecological system of Arctic charr (Salvelinus alpinus) fishing and aquaculture as a tourism product in an era of climate change. Arctic charr is a resilient salmonid species that was traditionally an important part of the sustenance economy in Arctic and Subarctic communities as a source of fresh food throughout the year. Arctic charr populations have declined in recent years, in part due to climate change. These changes in the freshwater ecosystems in turn affect the cultural and economic traditions of freshwater fishing and consumption. This development has consequences for the tourism industry as hunting, fishing and consuming local and traditional food is important in branding tourism destinations. Fisheries are no longer the source of this important ingredient in the Nordic culinary tradition, instead aquaculture production supplies nearly all the Arctic charr consumed. In this paper, we pool the resources of an interdisciplinary team of scholars researching climate change, freshwater ecology, aquaculture and tourism. We integrate knowledge from these fields to discuss likely future scenarios for Arctic charr, their implications for transdisciplinary social ecosystem approaches to sustainable production, marketing and management, particularly how this relates to the growing industry of tourism in the Nordic Arctic and Subarctic region. We pose the questions whether Arctic Charr will be on the menu in 20 years and if so, where will it come from, and what consequences does that have for local food in tourism of the region? Our discussion starts with climate change and the question of how warm it is likely to get in the Nordic Arctic, particularly focusing on Iceland and Norway. To address the implications of the warming of lakes and rivers of the global north for Arctic charr we move on to a discussion of physiological and ecological factors that are important for the distribution of the species. We present the state of the art of Arctic charr aquaculture before articulating the importance of the species for marketing of local and regional food, particularly in the tourism market. Finally, we discuss the need for further elaboration of future scenarios for the interaction of the Arctic charr ecosystem and the economic trade in the species and draw conclusions about sustainable future development.

This paper presents the results of a community survey that was designed to better understand the effects of permafrost degradation and coastal erosion on civil infrastructure. Observations were collected from residents in four Arctic coastal communities: Point Lay, Wainwright, Utqiaġvik, and Kaktovik. All four communities are underlain by continuous ice-rich permafrost with varying degrees of degradation and coastal erosion. The types, locations, and periods of observed permafrost thaw and coastal erosion were elicited. Survey participants also reported the types of civil infrastructure being affected by permafrost degradation and coastal erosion and any damage to residential buildings. Most survey participants reported that coastal erosion has been occurring for a longer period than permafrost thaw. Surface water ponding, ground surface collapse, and differential ground settlement are the three types of changes in ground surface manifested by permafrost degradation that are most frequently reported by the participants, while houses are reported as the most affected type of infrastructure in the Arctic coastal communities. Wall cracking and house tilting are the most commonly reported types of residential building damage. The effects of permafrost degradation and coastal erosion on civil infrastructure vary between communities. Locations of observed permafrost degradation and coastal erosion collected from all survey participants in each community were stacked using heatmap data visualization. The heatmaps constructed using the community survey data are reasonably consistent with modeled data synthesized from the scientific literature. This study shows a useful approach to coproduce knowledge with Arctic residents to identify locations of permafrost thaw and coastal erosion at higher spatial resolution as well as the types of infrastructure damage of most concern to Arctic residents.

Mercury (Hg) is a global pollutant with adverse health effects on humans and wildlife. It is of special concern in the Arctic due to accumulation in the food web and exposure of the Arctic population through a rich marine diet. Climate change may alter the exposure of the Arctic population to Hg. We have investigated the effect of climate change on the atmospheric Hg transport to and deposition within the Arctic by making a sensitivity study of how the atmospheric chemistry-transport model Danish Eulerian Hemispheric Model (DEHM) reacts to climate change forcing. The total deposition of Hg to the Arctic is 18% lower in the 2090s compared to the 1990s under the applied Special Report on Emissions Scenarios (SRES-A1B) climate scenario. Asia is the major anthropogenic source area (25% of the deposition to the Arctic) followed by Europe (6%) and North America (5%), with the rest arising from the background concentration, and this is independent of the climate. DEHM predicts between a 6% increase (Status Quo scenario) and a 37% decrease (zero anthropogenic emissions scenario) in Hg deposition to the Arctic depending on the applied emission scenario, while the combined effect of future climate and emission changes results in up to 47% lower Hg deposition.

The general aim was to assess dietary exposure to selected persistent organic pollutants (POPs) and metals among Eskimo (Inuit) and Chukchi of the Chukotka Peninsula of the Russian Arctic, and to establish recommendations for exposure risk reduction.A cross-sectional evaluation of nutritional patterns of coastal and inland indigenous peoples of the Chukotka Autonomous Okrug (in 2001-2003); assessment of the levels of persistent toxic substances (PTSs) in traditional foods and their comparison to Russian food safety limits; the identification of local sources of food contamination; and the recommendation and implementation of risk management measures.Community-based dietary survey of self reported food frequencies (453 persons), chemical analyses (POPs and metals) of local foods and indoor matters (397 samples), substantiation of recommendations for daily (weekly, monthly) intakes of traditional food.POPs in traditional food items are generally below the Russian food safety limits except marine mammal fat, while Hg and Cd are high mainly in mammal viscera. Lead is relatively low in tissues of all animals studied. For the Chukotka coastal communities, seals constitute the principal source of the whole suite of PTSs considered. Consumption restrictions are recommended for marine and freshwater fish, some wild meats (waterfowl and seal), fats (whale and seal), liver (most animals) and kidney (reindeer, walrus and seal). Evidence is presented that contamination of foodstuffs may be significantly increased during storing/processing/cooking of food due to indoor and outdoor environmental conditions.Based on the analytical findings and the local PTSs sources identified, guidelines on food safety are suggested, as well as measures to reduce food contamination and domestic and local sources. Important and urgent remedial actions are recommended to minimize PTSs environmental and domestic contamination. Waste clean-up activities started in coastal Chukotka in 2007.

Hydroclimatic changes may be particularly pronounced in high-latitude regions and can influence infectious diseases, jeopardizing regional human and animal health. In this study, we consider the example of tularemia, one of the most studied diseases in high-latitude regions, which is likely to be impacted by large regional hydroclimatic changes. For this disease case, we use a validated statistical model and develop a method for quantifying possible hydroclimatically driven shifts in outbreak conditions. The results show high sensitivity of tularemia outbreaks to certain combinations of hydroclimatic variable values. These values are within the range of past regional observations and may represent just mildly shifted conditions from current hydroclimatic averages. The methodology developed also facilitates relatively simple identification of possible critical hydroclimatic thresholds, beyond which unacceptable endemic disease levels may be reached. These results call for further research on how projected hydroclimatic changes may affect future outbreaks of tularemia and other infectious diseases in high-latitude and other world regions, with particular focus on critical thresholds to high-risk conditions. More research is also needed on the generality and spatiotemporal transferability of statistical disease models.

Major pandemics involving respiratory viruses develop semi-regularly and require a large flux of novel viruses, yet their origination is equivocal. This paper explores how natural processes could give rise to this puzzling combination of characteristics. Our model is based on available data regarding the emergence of historic influenzas, early COVID-19 cases and spreading, the microbiome of permafrost, long-distance airborne transport of viruses reaching stratospheric levels, ultraviolet immunosuppression, sunlight variations, weather patterns, Arctic thawing, and global warming. Atmospheric conveyance is supported by hemispheric distribution disparities, ties of COVID-19 cases to air pollution particulate concentrations, and contemporaneous animal infections. The following sequence is proposed: (1) virus emergence after hot Arctic summers, predominantly near solar irradiance maxima or involving wildfires, indicates release of large amounts of ancient viruses during extensive permafrost melting, which are then incorporated in autumn polar air circulation, where cold storage and little sunlight permit survival. (2) Pandemics onset in winter to spring at rather few locations: from climate data on Wuhan, emergence occurs where the North Polar Jet stream hovers while intersecting warmer, moist air, producing rain which deposits particulates with the viral harvest on a vulnerable human population. (3) Spring and summer increases in COVID-19 cases link to high solar irradiance, implicating ultraviolet immune suppression as one means of amplification. (4) Viruses multiplied by infected humans at close range being incorporated in atmospheric circulation explains rapid global spread, periodic case surges (waves), and multi-year durations. Pollution and wind geography affect uptake and re-distribution. Our model can be tested, e.g., against permafrost stored in laboratories as well as Artic air samples, and suggests mitigating actions.

Hundreds of isolates of viable bacteria and fungi have been recovered from ancient ice and permafrost. Evidence supports the hypothesis that viral pathogens also are preserved in ice repositories, such as glaciers, ice sheets, and lake ice. Proof may depend upon narrowing the search by applying specific criteria, which would target candidate viruses. Such criteria include viral pathogens likely to occur in great abundance, likely to be readily transported into ice, and then participate in ongoing disease cycles suggestive of their having been deposited in and subsequently released from ice. Caliciviruses, influenza A, and some enteroviruses appear to satisfy all three criteria. Environmental ice appears to be an important abiotic reservoir for pathogenic microbes. World health and eradication of specific pathogens could be affected by this huge reservoir.Copyright 2004 Elsevier Ltd.

Climate change is impacting ecosystem structure and function, with potentially drastic downstream effects on human and animal health. Emerging zoonotic diseases are expected to be particularly vulnerable to climate and biodiversity disturbance. Anthrax is an archetypal zoonosis that manifests its most significant burden on vulnerable pastoralist communities. The current study sought to investigate the influence of temperature increases on geographic anthrax suitability in the temperate, boreal, and arctic North, where observed climate impact has been rapid. This study also explored the influence of climate relative to more traditional factors, such as livestock distribution, ungulate biodiversity, and soil-water balance, in demarcating risk. Machine learning was used to model anthrax suitability in northern latitudes. The model identified climate, livestock density and wild ungulate species richness as the most influential features in predicting suitability. These findings highlight the significance of warming temperatures for anthrax ecology in northern latitudes, and suggest potential mitigating effects of interventions targeting megafauna biodiversity conservation in grassland ecosystems, and animal health promotion among small to midsize livestock herds.

Climate change is affecting human health worldwide. In particular, changes to local and global climate parameters influence vector and water-borne diseases like malaria, dengue fever, and tick-borne encephalitis. The Republic of Sakha in northern Russia is no exception. Long-term trends of increasing annual temperatures and thawing permafrost have corresponded with the northward range expansion of tick-species in the Republic. Indigenous communities living in these remote areas may be severely affected by human and livestock diseases introduced by disease vectors like ticks. To better understand the risk of vector-borne diseases in Sakha, we aimed to describe the increase and spatial spread of tick-bite cases in the Republic. Between 2000 and 2018, the frequency of tick bite cases increased 40-fold. At the start of the period, only isolated cases were reported in southern districts, but by 2018, tick bites had been reported in 21 districts in the Republic. This trend coincides with a noticeable increase in the average annual temperature in the region since the 2000s by an average of 1 °C. Maps illustrate the northward spread of tick-bite cases. A negative binomial regression model was used to correlate the increase in cases with a number of climate parameters. Tick bite case frequency per district was significantly explained by average annual temperature, average temperature in the coldest month of the year, the observation year, as well as Selyaninov’s hydrothermal coefficient. These findings contribute to the growing literature that describe the relationship between tick abundance and spread in Northern Latitudes and changes in temperatures and moisture. Future studies might use these and similar results to map and identify areas at risk of infestation by ticks, as climates continue to change in Sakha.

<p>The reduction in the extent of summer sea ice, associated with global climate change, offers the possibility<br>of new sea routes through the Arctic Ocean. Improving the skill of forecasting sea ice and weather<br>would strongly support Arctic navigation. Collecting international online information (including observational<br>data, forecast products, and historical analysis) of the high Arctic, and analyzing the characteristics of<br>sea ice extent and weather forecast information, could support the development of operational Arctic forecasting<br>by China. By comparing the information supplied by seven Arctic countries, three non-Arctic countries,<br>and three international information suppliers, it was found that sea ice and meteorological forecasting<br>capabilities have improved considerably, although further improvements could be made. For example, observational<br>data have not been applied fully, the prediction ability in the Central Arctic remains weak, sharing<br>of forecast information is insufficient, and comparison is needed when using online information. Furthermore,<br>the development of new information technologies is urgently required. To provide improved and<br>reliable protection in relation to sea ice and weather for Chinese Arctic expeditions and shipping activities, it<br>is strongly suggested that investment in Arctic scientific expeditions be increased, and that international cooperation<br>be sought for the development of forecasting technologies in relation to areas affected by Arctic<br>sea ice.</p>

北极快速升温为北极通航窗口期延长提供了重大机遇, 为北极航运和极区科考船只的空间信息提供服务, 海冰边缘区浮冰遥感信息产品的可靠性非常关键。对比和分析了9种海冰密集度数据产品, 并采用高分雷达数据开展面向海冰边缘区精度评估。结果表明, 北极地区的9种海冰密集度产品相对其平均值的最大日偏差出现在夏季6—8月航道窗口期, 其中采用被动微波高频算法的ASI产品和综合算法OSI SAF产品的整体平均偏差分别为0.59%和–0.65%。经对比发现各产品空间分布的不一致性主要存在于海冰边缘区。 2018年, 9种产品海冰范围的逐日最大和最小值之差为2.51×10⁶~6.26×10⁶ km²。在边缘区采用高分辨率雷达数据开展对比, 结果表明在密集压实型海冰边缘, 除基于ASI和NT2算法的三种产品外, 其余六种产品均呈低密集度区高估、高密集度区低估的特点; 基于AMSR2传感器的ASI-AMSR2和OSI SAF-AMSR2产品与雷达观测具有较高相关性, R²分别为0.85和0.82, 且均方根误差(RMSE)最小, 分别为12.19%和9.70%。在分散型冰边缘, 各产品对海冰密集度全面低估, OSI SAF-AMSR2相关性最高, R²为0.78, RMSE最小, 为6.19%。分析认为基于AMSR2的OSI SAF-AMSR2产品在现有9种产品中更能表征航道区海冰边缘与低密集区。

Recent rapidwarming of the Arctic has promoted extension of the Arctic navigation period.However, the reliability of spatial information regarding the edge of the seaice area, provided by remote sensing products, is critical for safe operationof Arctic shipping and polar research vessels. We compared and analyzed ninesea ice concentration (SIC) products, and used high-resolution synthetic apertureradar (SAR) data to evaluate their accuracy in determining the sea ice edgearea. Results showed that the largest daily deviations from the mean values ofthe nine products occurred during the summer navigable window (June–August).Average deviations of ASI products with a passive microwave high-frequencyalgorithm and OSI SAF products with an integrated algorithm were 0.59% and−0.65%, respectively. The greatest inconsistency in spatial distribution amongthe nine products was found in the sea ice marginal area. In 2018, thedifference between the daily maximum and minimum sea ice extent of the nineproducts ranged from 2.51 × 106 to 6.26 × 106 km2.The SAR data were used for comparison with the nine products in the ice marginarea. In the closed pack sea ice marginal area, apart from the three productsbased on the ASI and NT2 algorithms, the other products overestimated(underestimated) the low (high) SIC area. The ASI and OSI SAF products based onAMSR2 sensors produced the highest correlation with the SAR data, with R2 values of 0.85 and 0.82, respectively, and root mean square errors (RMSEs)of 12.19% and 9.70%, respectively. However, in the drift sea ice edge area, allproducts underestimated SIC; the OSI SAF product had the highest R2 value (0.78) and lowest RMSE (6.19%). Of the nine products tested, theanalysis indicated that OSI SAF products based on AMSR2 sensors could betterrepresent the sea ice margin and low SIC areas in Arctic navigation channels.

北极西北航道对北极资源开发与世界贸易格局有重要影响。针对当前西北航道通航适宜性时空变化分析研究中时空分辨率低、时效性差等问题，利用2015—2019年每年9月及2019年8月1日至9月20日的Sentinel-1 SAR数据，基于k均值非监督分类方法反演了十米级高空间分辨率海冰密集度。通过长时序宏观跟踪和短时序精细分析西北航道全线通航窗口，并以70%的海冰密集度作为阈值，测算了西北航道经过重要海湾及海峡累计不可通航的次数。结果表明：西北航道的航情随冰情而变，通航能力尚不稳定。具体来说，西北航道的冰情呈现东轻西重、南轻北重的格局，不可通航节点个数东少西多、南少北多。2018年9月西北航道通航情况最差，高于可通航阈值的海冰覆盖面积占总航道面积的35.24%，共有10个不可通航节点。2016年和2019年9月的通航情况较好，阿蒙森湾—科罗内申湾—毛德皇后湾—维多利亚海峡—富兰克林海峡—皮尔海峡—巴罗海峡—兰开斯特海峡段航道（航道C）可实现全线通航。进一步通过小尺度时间窗口研究发现，西北航道的最佳通航窗口为8月下旬至9月上旬，期间共出现3条全线通航的航道；最佳通航路线为航道C，其连续通航时间长达30天。

The Arctic Northwest Passage has an important impact on the development of Arctic resources and the pattern of world trade. To address the problems of low spatial and temporal resolution and poor timeliness in the current study of spatial and temporal variability analysis of navigable suitability of the Northwest Passage， this paper made the following research. High-resolution Sentinel-1 SAR data and k-means method are used to estimate the ten-meter high spatial resolution sea ice concentration （SIC）. The navigable window of the Northwest Passage is determined through macro-tracking of long-term series and precision analysis of short-time series. Taking 70% SIC as the threshold， the cumulative number of times that the Northwest Passage failed to pass through important bays and straits was analyzed. The results show that navigation in the Northwest Passage varies with ice conditions， and its navigability is still unstable. Specifically， the ice situation in the Northwest Passage shows a pattern of light in the east and heavy in the west， light in the south and heavy in the north. The number of non-navigable nodes is less in the east and more in the west， less in the south and more in the north. Navigation of the Northwest Passage in September 2018 was the worst compared to other years during the study period. The area covered by sea ice above the navigable threshold accounts for 35.24% of the total channel area， with a total of 10 non-navigable nodes. In contrast， September 2016 and 2019 have better navigation. The A.G.—C.G.—Q.M.G.—V.S.—F.S.—P.S.—B.S.—L.S. section of the channel （Channel C） is fully navigable. Further studies through small-scale time windows revealed that the best navigable window for the Northwest Passage is late August to early September， during which a total of three fully navigable channels occur. Channel C is the best navigable route of the Northwest Passage， and its continuous navigable period is up to 30 days.

论文检索了科学引文索引(Web of Science)和中国知网(CNKI)中北极地区地缘关系的相关文献,借助CiteSpace文献分析软件的关键词共现分析功能,系统综述了2000年以来国内外关于北极地区地缘关系的研究重点。从研究内容上看,国外研究主要关注主权政治、航道利用、资源管理和原住民权益等主体性议题,而国内则着重关注地缘政治、航道交通、资源经济和地区治理等参与性议题。就研究方法上看,国内外研究中定性与定量方法兼具,但仍以定性方法和描述性方法为主。随着北极地区的发展,研究方法和研究视角有待丰富,研究领域和研究深度亟需进一步拓展和加强。北极地区具有重要的战略意义,未来应结合现代技术,借鉴国际上的地区发展理论,开展北极地区的可持续发展研究和中国参与研究,并构建新时代北极地区地缘环境理论。

In recent years, with the impact of climate change, the Arctic has aroused extensive concerns worldwide. In this article, we systematically reviewed the publications on geo-relations in the Arctic from 2000 to 2017 in both the English and the Chinese literature. We identified 289 articles in English and 596 articles in Chinese by searching in Web of Science and China National Knowledge Infrastructure (CNKI), respectively. In terms of the number of publications, 10 or fewer papers were published in both English and Chinese each year from 2000 to 2008, but there was a significant growth in numbers after 2009. The Keyword Co-occurrence function of the CiteSpace software was used to visualize the keywords of the searched publications for analyzing the research trend. In terms of contents, the publications in English focused on sovereignty, mainly involving continental shelf, the Svalbard archipelago, and the legal status of the continental shelf. Some studies focused on the economy and feasibility of transportation routes in the Arctic, considering navigational conditions and costs. In addition, the natural resources in the Arctic region, such as oil, gas, and fishery, were major topics in the English publications. By the influence of critical and humanistic geopolitics, the survival, interests, and rights of indigenous population were also discussed. In the Chinese literature, many scholars focused on the geo-relations among Russian Federation, the United States, and Canada. China's participation in Arctic affairs and Arctic governance were often discussed, such as identity construction and cooperation approaches. Being different from the English publications, the impact of Arctic Passages on the international economic order has been paid more attention to in the Chinese literature. Furthermore, many scholars discussed the influence, particularly on the economic field, of developing the Arctic region from a national perspective. In general, publications in English have mainly focused on sovereignty and politics, channel utility, resource management, and indigenous people's rights and interests in the Arctic, while the Chinese publications have paid more attention to geopolitics, transportation, resource utilization, and regional governance in the region. Although some studies were conducted by using quantitative methods, the majority of publications were rather descriptive. The research methods and research questions need to be developed in this research field. The Arctic is a region with strategic significance. In the future, in combination with the development of research methods and international regional development theory, sustainable development in the Arctic and China's participation need to be further studied, and a theory of geo-relations needs to be constructed and applied in the study of the Arctic.