Arctic Research Articles

Arctic copepod copper sensitivity and comparison with Antarctic and temperate copepods.

The ongoing global climate crisis increases temperatures in polar regions faster and with greater magnitude than elsewhere. The decline of Arctic sea ice opens up new passages, eventually leading to higher anthropogenic activities such as shipping, fishing, and mining. Climate change and anthropogenic activities will increase contaminant transport from temperate to Arctic regions. The shipping industry uses copper as an antifouling coating. Copper is an essential element but becomes toxic at excess concentrations, and its use may inadvertently affect non-target organisms such as copepods. Copper affects copepods by lowering reproductive output, prolonging developmental time, and causing increased mortality. As data on copper sensitivity of polar copepods at low temperatures are rare, we conducted onboard survival experiments with the Arctic region's most common copepod species (Calanus finmarchicus, C. glacialis, C. hyperboreus). Acute survival tests were done for up to 8 days on individuals in 70 ml bottles at 1 °C with nominal copper concentrations ranging from 3 to 480 μg L-1. We used a reduced General Unified Threshold model for Survival (GUTS) to analyse the data, and placed our results in the context of the few published copper sensitivity data of the Antarctic and temperate copepod species at low temperatures. The sensitivity of Cu exposure was similar between the three Calanus species. However, a model comparison suggests that the tested C. glacialis population is less sensitive than the other two species in our experiments. Compared to published data, the three Arctic species appear slightly less sensitive to copper compared to their Antarctic counterparts but more compared to their temperate ones. Our literature search revealed only a few available studies on the copper sensitivity of polar copepods. In the future, this species group will be exposed to more pollutants, which warrants more studies to predict potential risks, especially given possible interactions with environmental factors.

Characteristics of the Gut Microbiota Composition of the Arctic Zone Residents in the Far Eastern Region

Background. In many studies over the past decade, scientists have made a connection between the composition of gut microbiota and human health. A number of publications have shown that gut bacteria are involved in many metabolic and physiological processes of the organism. The composition of the gut microbiome is unique for each person and is formed under the influence of various factors associated with both the individual characteristics of the body and the characteristics of the environment. Different regional characteristics make it necessary for the body to adapt to certain conditions, including temperature fluctuations. Living in areas with low temperatures, such as the Arctic zone, dictates the need for increased energy consumption, which affects the composition of the gut microbiome. Methods. In our study, an extensive questionnaire was conducted among the participants, where many questions were included about the dietary preferences of the study participants, which allowed them us to further divide them into groups according to their diets. Stool samples were collected from participants from 3 groups: Arctic native, Arctic newcomer and the control group. The next step was the isolation of bacterial DNA and sequencing the 16S rRNA gene. The analysis of the results of the diversity of the intestinal microbiota was carried out both with and without taking into account the dietary preferences of the participants. Results. As a result of comparing the intestinal microbiota obtained from residents of the Arctic zone with the gut microbiota of residents of other regions with a milder climate, significant differences are found. These differences may be related to limited food resources and a reduction in the variety of food products characteristic of this Arctic region. t was also found that representatives of the bacterial families Christensenellaceae and Muribaculaceae dominated the control group, both with traditional nutrition and with a dairy-free diet in comparison with the Arctic groups. The control group was dominated by representatives of the Prevotellaceae, Enterobacteriaceae and Comamonadaceae families compared to the Arctic group (with a traditional diet). The results also show that the number of representatives of the families Desulfovibrionaceae (with traditional diet) and Enterobacteriaceae (with milk-free diet) is growing in the Arctic group. Conclusions. In the course of this work, bacterial families characteristic of people living in the Arc-tic zone of the Far Eastern region of the Russian Federation were identified. Poor diet, difficult climatic conditions, and problems with logistics and medical care can have a strong impact on the health of this population. The main type of diet for the inhabitants of the Arctic is the traditional type of diet. They consume a large number of low-cost products, obtainget animal protein from poultry and canned food, and also eat a small number of fresh vegetables and fruits. Such a diet is due to the social status of the study participants and the climatic and geographical features of the region (difficulties in agriculture). With such a diet, we observe a decrease in representatives of the Christensenellaceae, Muribaculaceae, Eubacteriaceae, and Prevotellaceae families and an increase in representatives of the Enterobacteriaceae and Desulfovibrionaceae families among Arctic residents. This imbalance in the futuremay cause, this population may to develop various diseases in the future, including chronic diseases such as obesity, intestinal dysbiosis, inflammatory bowel diseases, and type 2 diabetes.

A review of climate change impacts on migration patterns of marine vertebrates in Arctic and Subarctic ecosystems

Climate change is impacting marine ecosystems throughout the circumpolar Arctic, altering seasonal habitats and the food bases for fishes, seabirds, and marine mammals. Arctic and Subarctic regions provide resources for resident species and for species that migrate to the north from more southerly regions. Changes in northerly latitudes thus impact endemic as well as non-endemic animals. Herein, we review what is known about climate-driven changes in the migration patterns of Arctic and Subarctic marine vertebrates, including: 1) Arctic residents with seasonal movements – those fishes, seabirds, and marine mammals that complete their entire life cycle within the Arctic but exhibit seasonal movements; 2) Breeding migrants – many seabirds enter the Arctic to breed and subsequently migrate south in the fall; and 3) Summer visitors for feeding – certain species of boreal fishes, seabirds and marine mammals arrive during the northern summer to feed on abundant prey though they breed elsewhere. Migratory movements are often driven by the timing and extent of sea ice, which defines suitable habitat for some animals and limits access to open water and prey for others. Longer open-water seasons, warmer ocean temperatures, and stronger winds have resulted in earlier production blooms in spring and often, extended open-ocean plankton blooms into late summer, resulting in altered prey types and distributions. A common thread among taxa is that shifts in distribution and timing of migrating animals indicate they are traveling farther north, or shifting longitudinally, and migrations are occurring over longer seasonal time frames. Species performing multiple lifetime migrations or long-distance migrants may need to adjust migration timing or routing iteratively to match changes in marine productivity. Altered animal distributions or phenology, and reduced sea ice, affects access to animals that are critical nutritional, economical, and cultural components of Indigenous people’s lives in the Arctic. Ongoing changes challenge the resilience and adaptability of Arctic people and ecosystems, and will require adaptive research and management approaches.

Aeolus Winds Improve Arctic Weather Prediction

AbstractIt has been proven that assimilating winds from the Aeolus global Doppler Wind Lidar (DWL) would enhance the predictive skill of weather forecast models. In this study, we use a series of observing system experiments to examine how currently assimilated “operational” wind products and Aeolus winds impact environment and climate change Canada's global forecast system over the data‐sparse Arctic region. Aeolus winds improve the tropospheric wind and temperature forecasts by about 0.7%–0.9% of error reduction (a 15%–20% effect compared to the impact of operational wind products) while having little impact on specific humidity. In particular, Aeolus winds have an impact on forecasts of strong wind days on the wind and temperature fields that is double the impact for weaker wind days. On the other hand, the operational wind products do not show as large a discrepancy in impact between forecasts of disturbed and normal days. These findings suggest significant potential for global DWL observations to enhance severe weather prediction in polar regions.

The Republic of Korea’s Foreign Policy in the Arctic Region: Prospects for the Northern Sea Route

The Republic of Korea’s Foreign Policy in the Arctic Region: Prospects for the Northern Sea Route

Snow as an Indicator of Atmospheric Transport of Anthropogenic Particles (Microplastics and Microfibers) from Urban to Arctic Regions

We report anthropogenic particles (AP) > 100μm, including microplastics and microfibers, from 70 surface snow samples collected from the urban Greater Toronto Area (GTA), remote and sparsely inhabited regions in the Yukon and Northwest Territories, and the unpopulated high Arctic. Concentrations and proportions of particles of anthropogenic origin were conservatively estimated after blank and ‘anthropogenic origin’ corrections were performed based on visual analysis and micro-Fourier transform infrared spectroscopy (µFTIR). AP were dominated by microfibers (95-100%), with variable concentrations across and within regions. Microfibers were distinguished as synthetic, regenerated semi-synthetic, anthropogenically modified cellulosic, and natural cellulosic or proteinaceous. Among microfibers with confirmed anthropogenic origin, most were polyester/PET (8-22%) and semi-synthetic rayon (1-18%), with anthropogenic cellulose comprising a small proportion (3-7%) across all regional areas. Greater diversity of coloured non-fibrous particles (fragments, films and foams) in settled regions (i.e., GTA and Carcross, Yukon) suggests direct input from local sources. Back trajectory analyses performed for days leading up to sample collection showed high frequency transport (>10%) from population centres exceeding 200km distance. Our findings of APs in snow from uninhabited areas support the hypothesis that APs, especially microfibers, undergo long-range atmospheric transport whereby snow can scavenge and deposit APs in remote northern regions.

Review article: Retrogressive thaw slump characteristics and terminology

Abstract. Retrogressive thaw slumps (RTSs) are spectacular landforms that occur due to the thawing of ice-rich permafrost or melting of massive ground ice, often in hillslope terrain. RTSs occur in the Arctic, the subarctic, and high mountain (Qinghai–Tibet Plateau) permafrost regions and are observed to expand in size and number due to climate warming. As the observation of RTSs is receiving more and more attention due to their important role in permafrost thaw; impacts on topography; mobilization of sediment, carbon, nutrients, and contaminants; and their effects on downstream hydrology and water quality, the thematic breadth of studies increases and scientists from different scientific backgrounds and perspectives contribute to new RTS research. At this point, a wide range of terminologies originating from different scientific schools is used, and we identified the need to provide an overview of variable characteristics of RTSs to clarify terminologies and ease the understanding of the literature related to RTS processes, dynamics, and feedbacks. We review the theoretical geomorphological background of RTS formation and landform characteristics to provide an up-to-date understanding of the current views on terminology and underlying processes. The presented overview can be used not only by the international permafrost community but also by scientists working on ecological, hydrological, and biogeochemical consequences of RTS occurrence and by remote-sensing specialists developing automated methods for mapping RTS dynamics. The review will foster a better understanding of the nature and diversity of RTS phenomena and provide a useful base for experts in the field but also ease the introduction to the topic of RTSs for scientists who are new to it.

Research on Monitoring the Speed of Glacier Terminus Movement Based on the Time-Series Interferometry of a Ground-Based Radar System

The Tibetan Plateau (TP) is the largest glacier reserve outside the Antarctic and Arctic regions. Climate warming has affected the reserve of freshwater resources and led to frequent glacier disasters. However, due to its extreme environment of hypoxia and low pressure, it is extremely difficult to obtain data. Compared with other traditional monitoring methods such as makers and satellite remote sensing technology, Ground-Based (GB) radar systems have the advantages of convenient carrying and installation, sub-second level sampling, and sub-millimeter measurement accuracy. They can be used as an effective way to study the short-term rapid movement changes in glaciers. Based on a self-built GB radar system, monitoring experiments were conducted on two glacier termini on the TP. The movement speed of the Rongbuk glacier terminus on Mount Qomolangma was obtained through time-series interferometric measurement as 4.10 cm/day. When the altitude was about 5200 m, the glacier movement speed was 7.74 cm/day, indicating the spatial differences with altitude changes. And in another region, the movement speed of the Yangbulake glacier terminus on Mount Muztag Ata was 198.96 cm/day, indicating significant changes in glacier movement. The cross-validation of Sentinel-1 data during the same period proved the effectiveness of GB radar system interferometry in measuring glacier movement speed and also provided field validation data for remote sensing inversion.

Evolution of the Arctic Strategy of the USA and its Influence on the Foreign Policy Strategy of Russia in the Arctic

"Arctic" is translated from Greek as "northern" or as "bear", which is often associated with Russia and its efforts to develop this region. This is a single physical and geographical region of the Earth adjacent to the North Pole and including the margins of the continents of Eurasia and North America, almost the entire Arctic Ocean with islands (except for the coastal islands of Norway), as well as adjacent parts of the Atlantic and Pacifi c Oceans. The southern border of the Arctic coincides with the northern border of the tundra zone. Now the actions of the United States and NATO in the Arctic region have acquired a clearly anti- Russian character, which was especially manifested in the latest edition of the Arctic Doctrine of the United States. NATO's expansion into the region continues, the scale of the alliance's military exercises conducted there is increasing, which actively involve non-Arctic member countries of the bloc, which does not exclude the emergence of an armed conflict with Russia in the Far North.

Eco-physiological approach to assessing the functional state of workers in geological prospecting expeditions during meridian movement between mid-latitudes and the Arctic region

BACKGROUND: The current challenge lies in defining the unique characteristics of compensatory and adaptive mechanisms formation, as well as the development of healthcare technologies for various forms of work in Arctic region conditions. AIM: To study associations between climate patterns and physiological responses to daily fluctuations in meteorological factors. Specifically, we aimed to investigate how these factors impact the cardiovascular system and psychophysiological well-being of workers during geological prospecting expeditions along the meridian travel between Tyumen (57° 09’ N) and Yamal (71° 11ʹ N). MATERIAL AND METHODS: A total of 115 men aged 20–40 years in mid-latitude conditions (baseline data) and during occupational relocation to the Arctic region comprised the sample. The examination included recording key indicators of the cardiovascular system (heart rate, blood pressure, mean arterial pressure, pulse pressure), ECG in standard unipolar and augmented leads, and psychophysiological assessments (evaluation of trait and state anxiety, stress diagnostics, regulation of self-control, and emotional lability). Additionally, to calculate the natural and climatic contrast of regions in Western Siberia, meteorological data and geomagnetic activity indicators were analyzed based on eight daily measurements over 12 months across 11 years using a unified system of meteorological station indicators in Tyumen and Kharasavey. RESULTS: The cardiovascular system experiences desynchronosis during meridian movement from middle latitudes to the Arctic region. This condition is influenced by the interregional climatic contrast and the differences in daily rhythm characteristics of meteorological data between the initial and final destinations. The interaction within the system of meteorological rhythms plays an important role in these variations. CONCLUSION: The established associations within the ‘meteorhythms–biorhythms’ system underscore the necessity for developing regional norms for chronophysiological parameters of a healthy individual under specific environmental and climatic conditions. It also highlights the importance of dynamic monitoring of deviations in these parameters during occupational relocations between mid-latitudes and the Arctic region across different seasons. This approach is essential for the effective monitoring of maladaptive disorders and for predicting the potential development of pathologies.

Bacterial phylotypes associated with rock-dwelling Umbilicaria Lichens from Arctic/Subarctic areas in North America and Northern Europe

AbstractThe diversity of bacteria associated with lichens has received increasing attention. However, studies based on next-generation sequencing of microbiomes have not yet been conducted in the Arctic and Subarctic regions. In this study, rock-dwelling lichens belonging to the Umbilicariaceae family were sampled from the Arctic and Subarctic biological zones. The primary research purpose was to undertake a comparative investigation of the bacterial composition and diversity, identify potential indicators, and explore their potential metabolic pathways. 18S rRNA gene sequences of the fungal partner belonging to the genus Umbilicaria (Ascomycota) and the algal partner affiliated with the lineage Trebouxia (Chlorophyta). Comparing Umbilicaria spp. with a previous study in the Antarctic zone, the fungal partners were more inclined to cluster by sampling region. Operational taxonomic units (OTUs) were established based on a predetermined similarity threshold for V3-V4 sequences, which were ascribed to 19 bacterial phyla, and ten of them were consistently present in all samples. The most distinct zonal indicator genera based on OTU frequencies from Arctic and Subarctic lichens were Capsulimonas (Armatimonadota) and Jatrophihabitans (Actinomycota), respectively. Although the Subarctic zone had higher biodiversity and species richness based on alpha-diversity, the beta-diversity showed that the main species of bacterial communities were not significantly different, and the predictions of metabolic pathways based on the bacterial microbiome in lichen samples from the two zones were similar. These findings provide evidence that the geographical and/or bioclimatic environment and the different lichen-forming fungal species mainly and partially influence bacterial microbiomes and metabolic pathways.

A study of cognitive functions in elderly men from the Arctic region of the Russian Federation with arterial hypertension using the auditory event-related potentials P300

AIM: To study the effect of arterial hypertension on cognitive functions by evaluating the auditory event-related potentials (ERP) Р300 in men aged 60–74 years from the Arctic region of the Russian Federation with the special emphasis on men receiving antihypertensive therapy with controlled arterial hypertension and those who either do not take antihypertensive drugs or take them both regularly and irregularly without controlling blood pressure. MATERIAL AND METHODS: The study included 64 men with arterial hypertension and 19 men without hypertension (n=19) in Arkhangelsk. Registration of the Р300 and N2 components was performed using the Neuron-Spektr-4/VPM electroencephalograph (Neurosoft, Russia), utilizing the oddball paradigm. Blood pressure (BP) was measured with an automatic tonometer AD Medical UA-668 (Japan). RESULTS: In men without arterial hypertension and in those with controlled arterial hypertension, where the median values of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were within normal ranges, there were no differences in the latency (LT) of N2 and P300, nor in the magnitude of the P300 amplitude between these groups. In contrast, men who do not take antihypertensive drugs or receive antihypertensive therapy both regularly and irregularly without controlling their blood pressure, and who have SBP and DBP above normal values, showed an elongation of LT N2 in the parietal (P3), central (C3), and middle temporal (T3) sections on the left, and in the frontal section on the right (F4). There was also an elongation of LT P300 in the middle temporal region on the right (T4) and frontal regions on the right (F4), along with a decrease in the median values of the P300 amplitude in the anterior-temporal (F8, F7) parts of the brain. This indicates a deficit in attention, an increase in the time required for primary recognition and differentiation of signals, and a reduction in the speed of information processing and decision-making. CONCLUSION: In older men, SBP above 140 mmHg and DBP above 90 mmHg are associated with cognitive impairment as determined by the auditory event-related potentials P300.

Artificial light at night reveals hotspots and rapid development of industrial activity in the Arctic

Climate warming enables easier access and operation in the Arctic, fostering industrial and urban development. However, there is no comprehensive pan-Arctic overview of industrial and urban development, which is crucial for the planning of sustainable development of the region. In this study, we utilize satellite-derived artificial light at night (ALAN) data to quantify the hotspots and the development of light-emitting human activity across the Arctic from 1992 to 2013. We find that out of 16.4 million km2 analyzed a total area of 839,710 km2 (5.14%) is lit by human activity with an annual increase of 4.8%. The European Arctic and the oil and gas extraction regions in Russia and Alaska are hotspots of ALAN with up to a third of the land area lit, while the Canadian Arctic remains dark to a large extent. On average, only 15% of lit area in the Arctic contains human settlement, indicating that artificial light is largely attributable to industrial human activity. With this study, we provide a standardized approach to spatially assess human industrial activity across the Arctic, independent from economic data. Our results provide a crucial baseline for sustainable development and conservation planning across the highly vulnerable Arctic region.

Artificial intelligence for predicting arctic permafrost and active layer temperatures along the Alaskan North Slope

AbstractClimate change in Arctic regions poses a threat to permafrost stability, potentially leading to issues such as infrastructure damage, altered ecosystems, and increased greenhouse gas emissions. The challenge of monitoring permafrost temperatures and identifying critical environmental factors is accentuated by the scarcity of subsurface thermal data in remote Arctic locales. To alleviate this lack of soil thermal data we set out to combine in situ observed soil temperatures with MERRA-2 reanalysis data and Machine Learning (ML) to develop local and season-specific subsurface soil temperature predictions in Alaska. First, reanalysis features are selected based on surface energy budget physics. Coupled with Julian calendar dates, reanalysis features are preprocessed and then fed to the ML prediction model. We conducted a series of computational experiments and tested the results against performance benchmarks to determine the optimal prediction models, length of look-back period of model inputs, and the training set size. Six conventional ML models (e.g., GBDT, RF, SVR) and five statistical baselines (e.g. ARIMA) using in situ time series of soil temperature data ranging from 0 - 1 m depth are considered for the prediction task. The models are trained using in situ soil temperatures at depths between 0 and 1 m, spanning 16+ years, from field sites at Deadhorse and Toolik Lake, Alaska. All prediction performances are assessed using root mean squared error (RMSE) and mean absolute error (MAE). Results show that locally trained ML models can estimate shallow soil temperatures with an average error of $$RMSE=1.308^{\circ }$$ R M S E = 1 . 308 ∘ C.

The strategic insights of Arctic sea routes for the sustainable development of Taiwan's shipping industry

In recent years, the Arctic Ocean has been experiencing the impacts of climate change. Global warming has led to the melting of ice caps and a significant reduction in ice coverage. As a result, the Arctic Ocean has indirectly opened up two new shipping routes known as the “Northeast Passage" and the “Northwest Passage." The opening of these new routes has the potential to transform Northeast Asia into a major transshipment hub, linking the Indo-Pacific and Europe regions. Novel business models are also generated and investigated within the maritime industry. This study involved conducting semi-structured interviews with potential stakeholders from industry, government, and academia. Additionally, qualitative analysis software- NVivo11 was utilized along with grounded theory for data analysis. The rationale supporting this view includes the advantages of Taiwan's shipping industry, its strategic geographic location, and the potential for shorter shipping routes through the Arctic. Additionally, Taiwan can establish conducive conditions to enhance its international standing and diplomatic relationships concerning Arctic Ocean matters. This initiative will facilitate the sustainable development of Taiwan's maritime industry in the Arctic region.

Consequences of the war in Ukraine on the Arctic: an analysis of post-conflict macro-scenarios

Russia’s invasion of Ukraine has opened a Pandora’s box with certain global consequences. From the beginning of the invasion, the first effects on government, research and economic activities also appeared. This conflict has radically changed the dynamics of security in the Arctic. The deterioration, unprecedented since the end of the Cold War, in relations between Russia and the West has meant that cooperation between the two blocs has also disappeared in the main and perhaps the only region of the globe still spared from political tensions.The outbreak of the conflict led to a breakdown in cooperation and an escalation of military tensions in the Arctic. How these disputes end will be decisive in determining the Arctic region’s future political and strategic balances.The seven remaining Arctic states denounced Russia’s operation in Ukraine from the start, thus suspending all activities related to the Arctic Council. This is an immediate consequence and it indicates rapid and challenging changes for Arctic governance.

Relevance of the “Polar Index” Project for Sustainable Development of the Russian Sector of the Arctic Zone

Introduction. The following study answers the question whether the “Polar Index” project is a reliable reflection of the development of the Russian Arctic region in the field of sustainable development. Within the framework of this scientific work, the analysis of the general methodology for calculating the "Polar Index" assigned to each of the companies operating in the Russian Arctic was carried out. The analysis made it possible to understand the logic of assigning an organization to one of the three groups, depending on how active its sustainable development policy is.Materials and methods. The materials used in the given article include studies of Russian scientists devoted to sustainable development of the Arctic region, as well as the materials published on the official web-sites of Russian energy companies. In terms of research methodology, the article pays special attention to event analysis aimed at identifying and interpreting key activities and projects that are implemented by Russian companies in the Arctic zone within the framework of sustainable economic, social and environmental development. In order to do this, three Russian energy companies of different levels of participation in the development of the region were selected. Next, for each of these companies, an analysis of its actions and development strategy regarding the Russian segment of the Arctic was carried out.Results of the study. The comparison of the assessment of Russian energy companies’ activities based on the Polar Index and the conclusions regarding the effectiveness of their activities obtained as a result of the event analysis proves that the Polar Index project indeed reflects the effectiveness of the activities of Russian companies in the Arctic region, as well as the degree of their involvement in sustainable development of the polar region in question, with a high degree of reliability.Discussion and conclusion. The research revealed Russian companies, the activities of which to a substantial degree comply with all the three criteria of sustainable development, namely, economic, ecological, and social. That being said, relevant scientific research on the given subject demonstrates that the companies, which managed to achieve the best results in the given sphere, are Rosneft, Norilsky Nikel and Gaspromneft.

Numerical evaluation of ground source heat pumps in a thawing permafrost region

Permafrost degradation poses significant environmental and geological challenges in Arctic and subarctic regions, particularly in areas like Umiujaq, Canada. The warming climate leads to thawing permafrost, causing ground instability, disrupting hydrology, and impacting local built environment. This study evaluates the use of Ground Source Heat Pump (GSHP) operation for mitigating ground subsidence in a permafrost region using a two-dimensional Thermo-Hydro-Mechanical (THM) coupled finite element analysis considering the ground poro-elastic and poro-plastic responses. The research uses a single-well scenario to demonstrate the interactions among thermal, hydraulic, and mechanical processes. The impact of GSHP operation under different temperature management strategies, including a scenario with a constant GSHP temperature of −5 °C throughout the year is numerically investigated. Results indicate that GSHP operation exacerbates ground deformation near the borehole, particularly during winter months. However, maintaining GSHP operation throughout the entire year can mitigate extreme subsidence fluctuations, leading to a more stable subsurface environment. While GSHP systems provide effective thermal regulation, their operation can introduce mechanical stresses that potentially disturb the ground close to the borehole. Therefore, careful design, operation, and further research are essential to balance thermal benefits with ground stability in permafrost regions.

The beetle fauna (Coleoptera) of the arctic mainland of Norway

This paper is the first attempt to summarize the beetles present in the arctic region of the mainland of Norway since 1946. In 1995 and 1998 beetles were collected by pitfall traps and other methods in Vardø municipality on the Varanger Peninsula in Finnmark county. This area is part of the small section of the Norwegian mainland that belongs to the southern arctic vegetation zone. A total number of 159 species from 18 families were recorded, including earlier findings by others. This probably covers a substantial part of the beetle fauna present in this marginal environment. Rove beetles (Staphylinidae) are the most abundant group and made up 46% of the recorded species, whereas diving beetles (Dytiscidae) and ground beetles (Carabidae) made up 16% and 15% of the species, respectively. Considering the regional distribution of these species in Norway, 8% are found only in northern Norway (Nordland/Troms/Finnmark), 19% have mainly an alpine distribution, 27% are mainly restricted to boreal areas, whereas 53% are common all over Norway. Diacheila polita and Simplocaria elongata belong to a characteristic arctic beetle community, and the present records of these two species are the only ones from Scandinavia. The study indicates that there are very few beetles that belong entirely to the arctic mainland of Norway.

Manifold increase in the spatial extent of heatwaves in the terrestrial Arctic

It is widely acknowledged that the intensity, frequency and duration of heatwaves are increasing worldwide, including the Arctic. However, less attention has been paid to the land area affected by heatwaves. Here, using atmospheric reanalysis and global climate models, we show that the area covered by heatwaves is substantially expanding in the terrestrial Arctic. Compared to the mid-20th century, the total land area affected by severe heatwaves in the Arctic has doubled, the area of extreme heatwaves has tripled, and the area of very extreme heatwaves has quadrupled. Furthermore, climate model projections suggest that the extent of heatwaves will continue to increase in the 21st century, but with large regional differences in heatwave magnitudes due to summer intraseasonal temperature variability. Our findings underscore the growing vulnerability of the Arctic region to extreme heat, potentially leading to severe impacts on both ecosystems and societies.