Antarctic ice-free areas (<0.4% of the continent) represent Antarctic biodiversity oases, where microbial communities sustain terrestrial ecosystem functions. These habitats—encompassing mineral, ornithogenic soils, biological soil crusts, and hypolithic/endolithic niches—are shaped by environmental factors such as pH, organic C/N ratios, moisture, elevation, and trace element availability. The diversity of prokaryotes, eukaryotes, and viruses is lower than in other regions, yet the communities exhibit strong endemism, with site-specific uncultivated lineages. Microorganisms persist through cold and stress adaptations, performing organic carbon decomposition, phototrophy, and oxidation of trace gases to drive carbon and nitrogen cycling in various Antarctic soil habitats. Climate change and anthropogenic disturbances are shifting communities toward copiotrophic generalists, altering elementary cycling and feeding back to climate change. Culturation and genomic-based techniques reveal novel microbial taxa with broad biotechnological potentials on bioactive compounds and cryotolerant enzymes. In summary, this review offers a foundation for exploring Antarctic microbial biodiversity, ecosystem resilience, and the development of novel biotechnologies, while also highlighting the urgent need for effective monitoring and preservation strategies to mitigate the impacts of ongoing environmental changes on Antarctic soil ecosystems.

Under ongoing global warming, reliable projections of Arctic sea-ice conditions and future navigability are of strategic significance. Using a combination of observational and physical constraints, we systematically evaluated the performance of 48 Coupled Model Intercomparison Project 6 (CMIP6) models in simulating Arctic sea ice and selected 12 skillful models for detailed analysis. Navigability of the Northeast Passage (NEP), Northwest Passage (NWP), and Transpolar Sea Route (TSR) during 2015–2100 was assessed under Shared Socioeconomic Pathways (SSP) 2-4.5 and SSP5-8.5 scenarios. Results indicate that for open water vessels under the SSP2-4.5, TSR is not projected to become navigable until 2029. In contrast, under the SSP5-8.5 scenario, both NWP and NEP are expected to support year-round navigation by the late 21st century, while TSR is not anticipated to become fully operational until after 2090. Polar Class 6 vessels achieve near year-round navigation by 2100 under SSP2-4.5, and full-year operation as early as 2048 under SSP5-8.5.

Understanding the sediment record during the Little Ice Age (LIA) can help elucidate natural sea ice fluctuation and carbon cycle variability. This study analyzed the grain size composition (including ice-rafted debris), total organic carbon (TOC), total nitrogen (TN) content, and stable isotopic composition (δ¹³C and δ¹⁵N) of the sediment record (approximately 490 a) of core ARC7-R11 in the northern part of the Chukchi Shelf. The sediment grains comprise mostly (>90%) silt and clay components. The grain size composition suggests generally low-energy hydrodynamic conditions across the region, yet reveals a trend of enhancement in hydrodynamics from the bottom to top layers of the sediment core, particularly after the 1940s. It also shows occurrences of seasonal sea ice and retreat of the perennial sea ice margin during warmer periods of the LIA and the post-LIA period. The organic matter content is high throughout the core, with heavier δ¹³C values and moderate TOC/TN ratios indicating primarily marine origin; the terrestrial input is <37.5% according to the endmember model. The variation trend of marine-derived organic carbon (OC) content is similar to that of summer temperature anomalies; while variation trend of terrestrially derived OC shows significant correlation with that of the number of ice-free days in the southern shelf region, except for the period from approximately 1700s to the 1870s. During the LIA, the TOC content fluctuated and decreased, and the relative contribution of terrestrial OC was higher than during the modern warm period. The amount of OC buried in the sediment has increased with climate warming, especially after the 1940s, reflecting the enhanced ability of sediment to sequester carbon during warmer periods.

The extreme environment of the polar regions has driven the evolution of unique metabolic mechanisms in microorganisms, resulting in structurally diverse and highly active secondary metabolites. These metabolites are not only crucial for microbial adaptation to extreme conditions, but also exhibit significant potential for applications in medicine, agriculture (e.g., biocontrol), and industry. This review provides a comprehensive overview of 111 secondary metabolites derived from polar microorganisms reported between 2013 and 2025, with a focus on advances in their classification, biological activities, and biosynthetic gene cluster mining techniques. Additionally, it highlights key strategies for advancing future investigations, providing a valuable reference for continued exploration in this promising field. Notably, polar microbial secondary metabolites also hold promising applications in agriculture, particularly in biocontrol, soil health enhancement, and stress-resistant crop development.

On 19 June 2023, the Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction (BBNJ Agreement) was adopted. The BBNJ Agreement aims to regulate the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction, including the high seas and the international seabed area. The BBNJ Agreement enters into an already crowded institutional landscape as a global authority with broad objectives, inevitably interacting with existing institutions, frameworks, and bodies (IFBs). Existing research has primarily focused on two areas: the first examines the impact of the institutions established by the BBNJ Agreement on existing marine governance IFBs; the second explores its influence on issues currently lacking institutional arrangements. However, comparatively little attention has been given to the Agreement’s potential impact on governance gaps within established systems. This paper takes the case of marine genetic resource (MGRs) management in the Antarctic Treaty Area to explore how the BBNJ Agreement may address regulatory gaps in a competent governance framework. Due to shortcomings in addressing core issues, concerning the legal status of MGRs access regulations, benefit-sharing mechanisms, and disclosure of origin, the Agreement is unlikely to have a significant impact on the governance of MGRs in the Antarctic Treaty System (ATS) in the short term. On the other hand, the ATS, as an effective governance framework for the Antarctic Treaty Area, has mature regulations and practical experience in Antarctic governance. Over the years, the ATS has focused on regulating bioprospecting activities as scientific research ones and strict environmental impact assessment procedures. However, there has not been an effective consensus on the regulation of commercial biological prospecting. This paper further explores the coordination issue between the BBNJ Agreement and the ATS, suggesting that in the future, MGRs governance in the Antarctic Treaty Area may evolve into a polycentric governance system.

The Prydz Bay-Prince Charles Mountains region in East Antarctica constitutes an exceptional geological transect for investigating continental evolution from the Archean to the Phanerozoic and its relationship with supercontinent cycles. This region preserves a complex record of magmatism, metamorphism, and tectonic reworking. Studies by the Chinese National Antarctic Research Expeditions in this region have yielded critical insights into the geological evolution of Antarctica. Key advances over the past decades encompass the elucidation of the Pan-African and Grenvillian tectono-metamorphic history, the delineation of the continent’s crustal and lithospheric architecture, and the identification of extensive ultrahigh-temperature metamorphism and rare mineral assemblages. Despite these advances, many fundamental questions remain unresolved. The spatial and temporal extents of ancient orogenesis are poorly constrained across different crustal blocks, and the tectonic drivers of extreme metamorphism continue to be debated. The role of deep lithospheric architecture in controlling both past orogenic processes and present-day glacial isostatic adjustment remains underexplored. Furthermore, the origins of ancient cratonic nuclei and their constraints on early Earth geodynamics warrant further investigation. Future research should prioritize integrated, multi-disciplinary approaches that combine geological and geophysical analyses. Key objectives include delineating the architecture and evolution of subglacial basement, reconstructing the Phanerozoic uplift and erosion history of the orogens, and evaluating feedback mechanisms among lithospheric evolution, ice-sheet dynamics, and long-term climate. Holistic cross-disciplinary investigations will be essential to unravel the connections between deep Earth processes and surface systems in one of the planet’s most enigmatic and geologically significant regions.

Prydz Bay, East Antarctica, is a critical region for studying ocean–sea ice–ice shelf interactions and their role in the global climate system. This review synthesizes the advancements in numerical modeling of physical oceanographic processes in Prydz Bay, highlighting the evolution from early one-dimensional thermodynamic models to contemporary high-resolution, three-dimensional coupled ocean–sea ice–ice shelf frameworks. We discuss key milestones in understanding processes such as frazil ice dynamics and its impact on the basal mass balance of the Amery Ice Shelf, the pathways and mechanisms of Modified Circumpolar Deep Water intrusions, and the dynamic influences of large icebergs on regional circulation. Despite significant progress, challenges remain in integrating multi-component interactions and achieving long-term, high-resolution climate projections. Future efforts should focus on developing fully coupled models that incorporate atmosphere–ocean–sea ice–ice shelf–iceberg interactions, supported by enhanced observational networks and improved computational efficiency. This review underscores the importance of continued modeling advancement to better predict the responses of Antarctic ice shelves and polar climate to global change.

The North Water Polynya (NOW) is one of the largest and most productive polynyas in the Arctic. Compared to the surrounding sea ice, the combination of high winds and cold air, together with the thin ice or open water surface of the NOW, produces large turbulent heat fluxes (THFs). The accurate estimation of these parameters requires high-resolution atmospheric data, which can be provided by the reanalysis products from different sources. In this study, we calculated the winter latent heat flux (LHF) and sensible heat flux (SHF) over the NOW and its surrounding sea ice area from 2005/2006 to 2015/2016 using high-resolution (15 km) Arctic System Reanalysis version 2 (ASRv2) data and low-resolution (30 km) European Centre for Medium-Range Weather Forecasts ERA5 data. Results show that the LHF/SHF over the surrounding sea ice is about 82%/88% lower than over the NOW, as estimated using either dataset. Furthermore, within each area, the difference in the THFs estimated from the two datasets is small. The spatial distribution of the LHF/SHF estimated from both data sources is similar to that of sea ice concentration. The average LHF/SHF in the polynya obtained using ASRv2 data is only 5%/7% higher than that from the values obtained using ERA5 data. This is because the wind speed and air temperature from the ASRv2 data are higher than those of ERA5, and their effects on the THFs can cancel each other out. Furthermore, the estimated THFs do not necessarily improve with the refined resolution of ASRv2.

Fine-scale structures can be observed in small field-of-view (FOV) auroral observations, but they are often overlooked because they appear only sporadically in all-sky observations. Such forms are of great interest because they may embody specific magnetosphere-ionosphere coupling processes, reveal localized energy deposition pathways, and provide new insights into cross-scale plasma dynamics and instabilities. However, their limited spatial extent, transient occurrence, and scarcity in wide-FOV observations make systematic investigation challenging. Traditional manual analysis struggles to capture these subtle structures within vast all-sky datasets, while automated detection faces severe data imbalance and morphological ambiguity. To address these challenges, we propose a synthetic-to-real progressive learning framework for cross-FOV retrieval of rare auroral forms. A Generative Adversarial Network (GAN) is employed to perform cross-FOV transformation between unpaired small-FOV images containing rare aurora forms and all-sky images (ASI) without such structures, thereby generating large numbers of synthetic ASI with rare auroral morphology. These synthetic samples are used to train an initial detection model, which subsequently undergoes iterative fine-tuning through feedback-guided learning: The model performs inference on new all-sky data, and the progressively accumulated real detections are incorporated into the training set. Experimental results demonstrate that the proposed method achieves over 92% detection accuracy on ASI, enabling high-precision retrieval of small-scale auroral structures across large-scale observations. This framework provides a scalable and effective approach to rediscovering rare auroral phenomena in continuous all-sky monitoring, offering new opportunities for exploring the fine-scale dynamics of the upper atmosphere.

The Fildes Peninsula is among the Antarctic regions most affected by human activity. As the interface between terrestrial and marine ecosystems, the intertidal is a gateway for ecological and public health risks. Antibiotic resistance genes (ARGs) and virulence factor genes (VFGs) intensify these risks by transferring pathogenic traits via horizontal gene transfer. However, a comprehensive assessment of ARGs and VFGs in Fildes Peninsula intertidal sediments is lacking. We addressed this gap by performing shotgun metagenomic sequencing on 14 intertidal sediments. We detected 20 ARG types comprising 397 subtypes. Multidrug, bacitracin, and polymyxin resistance dominated the resistome, although their overall abundance was relatively low. A total of 4,204 VFGs were identified and were primarily associated with adherence, motility, immune modulation, and effector delivery. The abundance of VFGs was also relatively low and significantly correlated with the abundance of ARGs. Additionally, we also identified 787 mobile genetic elements (MGEs) that carried 138 VFGs but found no ARGs associated with MGEs at the contig level. Host assignment implicated taxa such as Ilumatobacter as major ARG carriers and detected opportunistic pathogen Pseudomonas aeruginosa carrying CAM-1, a metallo-β-lactamase gene. In summary, our results reveal a highly diverse but generally low-abundance resistome and virulome in Fildes Peninsula intertidal sediments, with limited evidence for MGE-mediated ARG dissemination. However, they emphasize the necessity of monitoring to protect Antarctic microbial integrity.

Global warming has made the regular operation of Arctic routes possible. This study selects hub ports based on infrastructure conditions and sea ice status, and then designs two pendulum route solutions for the Northeast Passage according to the distance between hub ports and ice-covered areas. We employ an evaluation framework combining annual profit metrics with discounted net present value (NPV) analysis, conducting probabilistic economic assessments through Monte Carlo simulations (20,000 iterations). Key findings indicate that (1) both solutions demonstrate >90% probability of economic viability and (2) Solution I′, with hub ports closer to ice-covered areas than those in Solution II, yields 5.02% higher mean annual profit and 4.69% greater NPV. The results indicate that pendulum routes in the Northeast Passage can achieve economic benefits by enabling year-round regular operations. Moreover, shorter shipping distances between hub ports and ice-covered areas enhance economic viability.

The correlation between the Soil Moisture and Ocean Salinity (SMOS) L-band brightness temperature and thin sea ice thickness has been widely exploited using semi-empirical retrieval approaches based on a single-tie point (STP). However, due to pronounced spatial heterogeneity in seawater and sea ice properties across the Arctic, the use of an STP often leads to regionally biased. To address this limitation, this study proposes a multi-tie point (MTP) sea ice thickness retrieval method based on SMOS brightness temperature and sea ice concentration time series. Multiple seawater and sea ice tie-point values are identified through point-by-point time series analysis, quality control, and statistical hypothesis testing, allowing spatial variability in radiometric properties to be explicitly considered. The MTP-based retrieval is applied to Arctic freeze-up conditions. Validation against independent SMOS thin sea ice thickness products shows that the MTP approach yields significantly reduced bias and root mean square error compared with the conventional STP method, with statistically significant improvements confirmed by paired t-tests. While retrieval accuracy stabilizes beyond a certain number of tie points, the preprocessing cost associated with tie-point selection increases substantially. Considering both accuracy and efficiency, the MTP framework provides a practical and robust approach for large-scale Arctic thin sea ice thickness retrieval and enables improved characterization of regional freezing processes and maximum ice thickness.

To investigate the use of the three-point bending method and supplement the corresponding strength data of compacted snow for transportation-related applications in cold regions, compacted snow beams with an average density of 592?kg·m^?3 were fabricated and tested at three distinct flexural strain rates. Each strain rate corresponded to the ductile, transitional, and brittle behavior of compacted snow, respectively. The flexural strength, ranging from 0.518 to 0.933 MPa, peaks at the ductile-to-brittle transition, while the flexural modulus, varying between 48.97 and 287.72 MPa, increases with strain rate within the tested range. At the same strain rate corresponding to brittle failure, both mechanical properties of compacted snow exhibit higher values than those of natural snow tested by the authors. Notably, the flexural strain rate at the ductile-to-brittle transition for compacted snow identified in this study is comparable to those previously reported for natural snow under uniaxial tension. Additionally, the obtained strength data are thoroughly compared with existing literature, with detailed discussions provided. The loading rates associated with typical failure modes of compacted snow under bending, together with the obtained strength values, provide methodological guidance and reference data for future in situ testing of compacted snow structures.

This study investigates the potential formation of subglacial lakes beneath the glaciers of the Franz Josef Land archipelago, Russian Arctic, under current and future climatic conditions. Using a one-dimensional heat and mass transfer model, the research evaluates the influence of geothermal heat flow, ice thickness, and surface temperature on basal melting. The model incorporates enthalpy formulation and boundary conditions derived from field data, including temperature profiles and geothermal measurements. Results indicate that subglacial lakes could form under ice masses exceeding 300 m thickness, driven by geothermal heating, though current basal temperatures remain below the melting point. Simulations under the IPCC SSP1-2.6 scenario suggest a gradual warming trend, highlighting the long-term thermal inertia of Arctic glaciers. The study underscores the need for enhanced observational data to validate models and improve predictions of glacial dynamics in response to climate change.

 In recent decades, the Arctic has experienced persistent warming, with near-surface warming three to four times higher than the global average, accompanied by the melting of sea ice, snow cover, and ice sheets. This anomalous warming phenomenon is referred to as Arctic amplification (referred to as AA). With the recent advances in AA research, significant understanding has been developed regarding its temporal evolution, spatial distribution, and influencing mechanisms. However, controversies remain concerning the primary drivers of AA, the quantitative contributions of various drivers, and some of the underlying processes. This paper synthesizes recent research findings, revisiting the spatiotemporal characteristics of AA and its driving factors, and analyzes the influencing mechanisms from four perspectives, including albedo feedback, temperature feedback, aerosol–water vapor–cloud feedback, and poleward energy transport via ocean and atmosphere circulation. Existing studies are summarized to several major conclusions, including: AA is characterized by a short emergence time (appearing in the last ~40 years), a strong influence from underlying surface properties, albeit with significant seasonal variations; AA is influenced by a combination of drivers both within and outside the Arctic, and the interactions among these factors are highly complex, preventing a conclusive, overarching understanding of the formation mechanisms from being established. We suggest that future research would benefit from the following three key foci: (1) enhancing studies on the impacts of land surface albedo feedback, aerosols, the Atlantic Meridional Overturning Circulation, and stratospheric processes on AA; (2) optimizing parameterizations of cloud–aerosol and land surface processes in climate and Earth system models, and integrating sea ice drift dynamics into these models; and (3) investigating the interactive mechanisms among various driving factors from a holistic perspective.

A polyketide synthase–nonribosomal peptide synthetase gene cluster?twn?in?Talaromyces sp. HDN1820200?was activated by overexpression of the pathway-specific transcriptional factor TwnD. Large-scale fermentation and chemical investigation of the mutant strain?HDN1820200/TwnD led to the discovery of one new polyketide–amino acid conjugate, bipolamide C and one new polyketide compound, variotin A. The structures of the new compounds were determined by nuclear magnetic resonance (NMR) analysis, high-resolution electrospray ionization mass spectrometry, feeding experiments, NMR calculation and DP4⁺ analysis. This study revealed that the overexpression of the pathway-specific transcriptional factor represents a promising approach for the discovery of new natural products in fungi within specialized habitat.

Understanding microbial responses to polycyclic aromatic hydrocarbon (PAH) pollution is crucial for assessing the current status of PAH contamination in polar regions. In this study, intertidal and marine sediments were enriched with a mixture of PAHs (naphthalene, phenanthrene, fluorene, pyrene, and fluoranthene). Isolation of culturable bacteria, high-throughput sequencing, and functional prediction were combined to systematically analyze bacterial structural and predicted functional responses to PAH exposure. High-throughput sequencing results showed that the relative abundance of Proteobacteria was significantly increased after enrichment, and Pseudomonas and Acinetobacter were identified as dominant genera under PAH exposure. These findings were consistent with the 19 potential PAH-degrading strains (mainly Pseudomonas) that were successfully isolated from enrichment cultures. Distinct bacterial taxa between enriched marine and intertidal sediments indicated the existence of distinct PAH-degrading groups. PICRUSt2-based functional predictions suggested higher predicted abundances of PAH-degradation pathways in polar sediments, likely through the preferential degradation of parent PAH compounds in response to elevated concentrations. This study provides valuable data on microbial responses to PAH pollution in polar regions and offers new insights for evaluating ecological hazards induced by PAHs.

Phytoplankton play a pivotal role in the Southern Ocean ecosystem. This study examines the phytoplankton community structure and the environmental factors driving it in the Cosmonaut Sea, based on samples collected using a net during the summer of 2020/2021. We identified 99 phytoplankton species, predominantly comprising diatoms and dinoflagellates. Among these, diatoms—notably Pseudo-nitzschia, Chaetoceros, and Fragilariopsis, dominated the community in terms of species richness, abundance, and biomass. Endemic species of the Southern Ocean, such as Corethron pennatum, Proboscia alata, and Cylindrotheca closterium, also made significant contributions. Phytoplankton abundance and biomass showed similar spatial distribution patterns, with hotspots in the northern section of the survey area that gradually diminished towards the coastal regions. The oceanic area exhibited low phytoplankton diversity but pronounced regional variations in community distribution, with the northern region emerging as a key zone for abundance, biomass, and diversity. Nutrient distribution was identified as the primary environmental driver shaping the phytoplankton community, with silicate levels having a significant negative impact on overall phytoplankton abundance and the dominant species.

Global warming has led to a gradual extension of the navigable window for the Arctic Route, providing a realistic possibility for the normalized commercial operation of the Northeast Passage (NEP). Based on the changes in the navigable window of the NEP, Russia’s proposed nuclear-powered icebreaker construction scheme, and China’s potential development of a moderately sized ice-class fleet, this study establishes three scenarios for the commercial operation of the NEP. These scenarios include: (a) normalized summer operational scenario (from July to October each year), (b) normalized summer- autumn operational scenario (from June to January of the following year), and (c) normalized year-round operational scenario (12 months per year). The cargo transportation potential of the NEP under three normalized operational scenarios was predicted based on the grey prediction model. On this basis, construction scale plans for China’s ice-class fleet to meet cargo transportation demands under the three normalized operational scenarios were designed. The economic benefits of different plans were evaluated using a profit-maximization linear programming model. The research results show the following: (1) The cargo transportation potential of the NEP demonstrates a rapid growth trend in the future, with annual throughput under year-round normalized operations expected to exceed 100 million tonnes and reach 297 million tonnes. (2) Under different normalized operational scenarios, the fleet scale and vessel type composition vary. Under the normalized summer operational scenario, the optimal scale for China’s ice-class fleet is 20 vessels, consisting solely of ships classed as PC7 by the International Association of Classification Societies (IACS). Under the normalized summer-autumn operational scenario, the optimal fleet scale is 31 vessels, including 30 IACS PC7 ships and 1 IACS PC3 ship. Under the normalized year-round operational scenario, the optimal fleet scale is 45 vessels, composed of 30 IACS PC7 ships, 8 IACS PC3 ships, and 7 IACS PC2 ships. (3) Among the three normalized operational scenarios, the normalized year-round operational scenario yields the best economic benefits for the fleet scale, while the normalized summer operational scenario yields the lowest economic benefits.

Antarctic krill (Euphausia superba), widely distributes around Antarctica, is a key species supporting the biodiversity of the Southern Ocean ecosystem. The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) has thus managed the krill fishery according to a precautionary way. Currently, CCAMLR is making effort to develop a refined krill fishery management approach based on more solid science, which requires accurate predictions of krill distribution. To address this need, this study investigated the effects of algorithm and spatial resolution on the performance of Antarctic krill distribution modelling. We integrated acoustic data from 4 surveys conducted in the waters adjacent to the Antarctic Peninsula with 11 environmental variables characterizing krill prey conditions, water mass properties, and seafloor topography. These data were processed at 4 spatial resolutions (5, 10, 15, and 20 km) to fit distribution models using 4 algorithms: Random Forests (RF), Generalized Additive Models (GAM), Extreme Gradient Boosting (XGBoost), and Artificial Neural Networks (ANN). Model performance was assessed and compared in terms of goodness-of-fit and predictive accuracy. The results showed that RF achieved the highest predictive performance at most resolutions, whereas GAM performed best at the coarsest resolution (20 km). XGBoost closely following RF in accuracy and demonstrated robustness as evidenced by the highly consistent partial dependence curves across resolutions. In contrast, ANN exhibited limitations with smaller sample sizes, resulting in comparatively poorer predictive performance. The analysis revealed a trade-off whereby reducing spatial resolution improved model fit and mitigated zero-inflation at the expense of fine-scale information and overall predictive accuracy. Ensemble models, integrating RF, GAM, and XGBoost, are proposed as potential balanced solutions to improve predictive stability, offering a more robust scientific basis for the refinement of krill management.

Icy moons such as Europa and Enceladus are, beyond Earth, our solar system’s planetary bodies most conducive to support life and to contain the remnants of past life. Earth’s polar analogs prove that life can thrive in niche-specific conditions similar to those of subsurface oceans on the icy moons. Still, key microbiological questions remain that must guide our next steps in probing for life in future space missions. Research in polar microbiology can further illuminate or define possibilities of life in icy worlds.

The Antarctic geodetic datum constitutes a specialized implementation of the modern geodetic reference system within the extreme polar environment. A high-precision, unified, and dynamic Antarctic geodetic datum serves as critical infrastructure for polar scientific research and engineering safety. This study reviews the composition, current status, and implementation pathways of the Antarctic geodetic datum through four dimensions: coordinate datum, height datum, gravity datum and sounding datum. Preliminary analysis reveals that the development of the Antarctic geodetic datum framework is severely lagging, thereby failing to meet the demands of both scientific expeditions and polar research. To address these challenges, this study proposes an implementation pathway leveraging the 5th International Polar Year (IPY-5) to pioneer regional high-precision geodetic datum in the China’s key research sector covering the area between Amery Ice Shelf and Princess Elizabeth Land, specially highlighting the Prydz Bay–Amery Ice Shelf–Lambert Glacier–Dome A (PANDA) transect, by deploying multi-technique stations and μGal-level superconducting gravimeter networks; and then to integrate multinational observation resources to ultimately establish a high-precision, unified, and dynamic geodetic datum framework. This framework will deliver a spatiotemporal infrastructure for Antarctica to advance the strategic goals of “understanding, protecting, and utilizing Antarctica”.

Small RNAs (sRNAs) are important non-coding RNAs that usually play crucial roles in gene expression at the post-transcriptional level. The sRNAs have mostly been investigated in model microorganisms such as Escherichia coli and some pathogens. Nevertheless, microbial sRNAs from extreme environments such as the polar regions and deep sea have recently been discovered and analyzed for their unique roles in stress response, metabolic regulation and adaptation to extreme environments. These sRNAs fine-tune gene expression during oxidative and radiation stress, and modulate temperature and osmotic pressure responses. Representative sRNAs and their functions in thermophilic, psychrophilic, halophilic and radiation-tolerant bacteria are summarized in this review. Despite challenges in sample collection, RNA isolation, and functional annotation, the study of sRNAs in extreme environments provides opportunities for discovering novel regulatory mechanisms, applying them to biotechnology, and advancing our understanding of evolutionary adaptations. Looking ahead, high-throughput sequencing, synthetic biology, and multi-omics integration will bring new breakthroughs in discovering novel sRNAs and their functions and regulatory mechanisms. Such advancements are poised to enable comprehensive characterization of sRNA-mediated regulatory networks in extremophiles and unlock their biotechnological potential through mechanism-driven applications.

Research on Antarctic microbial diversity has primarily focused on 3 areas: freshwater lake sediments, penguin colonies, and seawater in ice-free regions. There is a scarcity of research on the impact of slopes on microbial community structure, and this study effectively fills this gap. This study focused on the soil in the sparse vegetated tundra on a hillside near the southern coastline of the Antarctic Great Wall Station. The influence of slope position, soil physicochemical properties, and vegetated area on soil bacterial community structure was analyzed. High-throughput sequencing technology was employed to characterize a 16S rRNA gene fragment in soil samples from 5 slope areas and estimate bacterial abundance. Calculation of α-diversity and β-diversity indices, and community structure analysis were used to compare the species richness among sampling points, analyze similarities in soil bacterial community structure and composition, and identify the core bacterial population. In the non-vegetated area, the soil on the mountaintop, hillside, and at the foot of the slope showed similar physicochemical properties. In the vegetated area, the soil physicochemical properties were highly similar on the mountaintop, hillside, the foot of the slope, and the foot of the mountain. Weighted Gene Co-expression Network Analysis showed that total organic carbon, pH, and PO₄^3–-P might affect the structure of bacterial communities at the sampling point by changing the relative abundance of Chthoniobacterales, Sediminibacterium, and Actinobacteria. We hypothesize that slope-driven nutrient transport, amplified by vegetated areas (in the tundra), is a primary driver of bacterial community structure in the Antarctic tundra soil. These results provide insights into the impact of slope on microbial community structure in Antarctica.

Samples for this study were collected from Geologists Island and Prydz Bay in different seasons. Otolith sections were analyzed for elemental composition in the nucleus, juvenile, and edge areas. Elements including Mg, Sr, P, K, Fe, and Zn, normalized to calcium (C_Me/C_Ca), were selected for analysis. To explore population structure, we studied factors influencing population dynamics during life stage, and regional distribution characteristics. For identified individual origins and explored the distribution and migration between regions and migration from hatching to adulthood provide a basis. So as to understand the distribution and migration pattern of Pagothenia borchgrevinki across various life history stages. Results indicated a consistent P. borchgrevinki population spawning across various regions of Southern Ocean, with eggs distributed at the bottom. Coastal slope topography changes and water compensation facilitated egg transportation from the bottom to under sea ice during hatching to juvenile stages. Long-distance migration was facilitated by the Antarctic Circumpolar Current and regional currents during development to adulthood. Multiple spawning grounds and ocean currents contributed to diverse distribution environments during the hatching period. Differences in individual development were important factors during the juvenile period, while ocean currents and autonomous behaviors influenced regional transportation patterns in the post development stages. Therefore, the research holds that differences in distribution environment and behavior during each period led to distinct factors influencing C_Me/C_Ca variations.

This paper explores the archaeology of whaling in Arctic prehistory, focusing on the emergence and development of whaling as a central component of cultural ecology among prehistoric Inuit and related societies. Drawing on archaeological evidence from key sites across Alaska, the Chukchi Peninsula, and the Bering Strait region, the study examines how whaling technologies and practices evolved alongside climatic fluctuations, ecological shifts, and social transformations. Integrating ethnographic insights and paleoclimatic data, the study argues that Inuit engagement with whales was not only a subsistence strategy but a long-term, historically contingent relationship that shaped and was shaped by broader cultural systems.

 The Arctic is warming rapidly, but the extent to which winter temperature extremes amplify relative to the global mean remains insufficiently quantified. Here we use four reanalysis datasets and large-ensemble simulations from the Polar Amplification Model Intercomparison Project (PAMIP) to assess winter Arctic extreme temperature amplification during 1979–2024 and its connection to sea ice loss. Across the reanalyses, winter Arctic daily mean temperature (T_mean), daily maximum temperature (T_max), daily minimum temperature (T_min) and the coldest daily minimum temperature (T_Nn) warm 3.7, 3.8, 3.9 and 4.7 times faster than their global means, respectively. The strongest response occurs over the Barents-Kara seas, where the warming rate of extreme temperature events exceeds six times the global mean. Singular value decomposition identifies a coupled pattern in which sea ice loss and extreme warming co-locate over the Barents-Kara seas. PAMIP experiments further show that prescribed Arctic sea ice loss generates coherent near-surface warming over major ice loss regions. The response is supported by enhanced turbulent heat fluxes, increased water vapor, stronger downward longwave radiation and a robust mid-tropospheric anticyclonic anomaly with subsidence warming. These findings underscore the critical role of sea ice–atmosphere coupling in shaping Arctic extreme temperature amplification and highlight the urgent need for further investigation and adaptive mitigation strategies. 

The Arctic serves as an indispensable component of the Earth’s coupled climate system, and imposes multi-scale, far-reaching modulation on global climate evolution, terrestrial and marine ecosystems, as well as global socio-economic development. Under ongoing global warming, the Arctic climate system has undergone pronounced accelerated shifts, characterized by amplified warming and wetting trends, drastic sea ice decline and increased heatwave occurrences. The Arctic climate system exerts pervasive global impacts via thermodynamic and dynamic pathways, including widespread cryospheric degradation, terrestrial climate extremes and remote teleconnections. Furthermore, accelerated Arctic climatic shifts can modulate diverse climate feedback loops, further complicating its multifaceted climatic impacts. Current frontiers in Arctic climate research include multi-source data coupling analysis, quantification of nonlinear feedbacks, Arctic-midlatitude teleconnections, and AI-assisted high-resolution Arctic climate prediction systems. To this end, we have organized a special issue addressing Arctic climate system variability and its global teleconnections, aiming to deepen insights into the system’s evolutionary processes, associated climatic impacts, and forecast skill.

Arctic warming has been widely documented, yet the relative contributions of processes controlling surface air temperature (SAT) and surface temperature (ST) warming remain insufficiently quantified, particularly between warm and cold seasons. Here, we use multiple reanalysis datasets to quantify Arctic SAT and ST warming from 1979 to 2021 through thermodynamic and surface energy budget analyses, with a focus on the seasonal contrast between warm season and cold season. We show that SAT warming in both seasons is primarily linked to an increase in the diabatic heating residual associated with surface warming, whereas cold season SAT warming is additionally enhanced by strengthened warm advection, which accounts for 33% of the total SAT increase. ST warming exhibits a stronger seasonal contrast. In the warm season, ST warming is driven jointly by enhanced downward longwave radiation, mainly associated with increased atmospheric water vapor, and sea ice albedo feedback, contributing 27% and 33% of the ST increase, respectively. In the cold season, ST warming is dominated by enhanced downward longwave radiation, with atmospheric water vapor, mid-level cloud cover, and a residual term mainly related to external greenhouse gas forcing contributing 36%, 16%, and 10%, respectively. The Arctic Ocean further modulates this seasonality by absorbing heat in the warm season and releasing it in the cold season, contributing 21% to cold season ST warming and providing an additional heat source for the lower atmosphere. These results demonstrate that recent Arctic warming cannot be interpreted from SAT or ST alone, but reflects seasonally distinct coupling among atmospheric heat transport, radiative feedbacks, sea ice loss, and ocean heat storage and release.

The transition from pack ice zone (PIZ) to marginal ice zone (MIZ) is a critical driver of Arctic climate change, significantly intensifying heat exchange within the atmosphere–sea ice–ocean system. This exchange is closely coupled with variations in the physical state and dynamics of sea ice. However, the evolution of sea ice properties during this transition remains insufficiently quantified. To address this problem, this study compares variations in key sea ice characteristics across three regions: perennial PIZ, PIZ transitioning to MIZ, and MIZ transitioning to open water. Results indicate that the transition from PIZ to MIZ coincides with accelerated ice loss, with the most pronounced declines in concentration (–1.3%·a^–1) and thickness (–0.04 m·a^–1) in September, and in area (–4.2×10⁴ km²·a^–1) in October. This transition is accompanied by a dramatic loss of multi-year ice, peaking at –1.8%·a^–1 in August. Furthermore, this transition corresponds to higher ice drift speeds and enhanced responses of sea ice motion to wind forcing, particularly in October (0.12 km·d^–1·a^–1 and 0.02 a^–1) when the transition extent reaches its maximum. An earlier melt onset on ice surface occurs in some parts of the transition region from PIZ to MIZ in May (–0.4 d·a^–1, P<0.05), and a delayed continuous freeze onset is observed in this transition region in October (1.0 d·a^–1, P<0.05). This transition region exhibits amplified sea ice changes relative to the pan-Arctic Ocean.

Against the background of global warming, especially the “Arctic amplification”, there has been a tension between the availability and economics of Arctic oil and gas resources and the extreme environmentality stipulated by the carbon neutrality goal. The research object is the interactions between China and Arctic oil and gas resources under the carbon neutrality goal. And China’s carbon neutrality process is proposed to be divided into four periods: 2020–2030, 2030–2040, 2040–2050, 2050–2060. The study finds as follows. First, the conflict between Russia and Ukraine has disrupted the existing interdependence between Russia and Europe in energy. Meanwhile, China and India both have uninterrupted demand for Arctic oil and gas resources from Russia. All has led to a new narrative on global energy security. Second, the possibility of ice-free Arctic Ocean in summertime makes the expansion of the navigation period of the Arctic shipping lanes possible. It has both advantages and disadvantages for China in Arctic energy consumption. Third, as the proportion of clean energy increases in China’s final energy consumption structure, China’s total demand for Arctic oil and gas resources declines correspondingly. Hence, China plays an independent role in the co-opetition with the United States and Russia. Fourth, by 2060, the co-opetition relationship between China, the United States, and Russia will undergo almost fundamental changes in the Arctic region. Those changes will be reflected in China’s increasing influence in Arctic energy distribution. Compared to typical research articles solely focused on the energy, this study has obviously theoretical, practical and methodological values.

As one of the most susceptible components of the global climate system, the Arctic undergoes rapid changes where aerosol properties play a pivotal role in modulating regional radiation budgets and climate feedbacks. Amid intensified Arctic amplification and expanding anthropogenic footprints, the chemical composition, sources, and cloud condensation nuclei activity of Arctic organic aerosols (OA) have emerged as critical research frontiers. This review synthesizes current knowledge on the seasonal dynamics and physicochemical evolution of Arctic OA, with a particular emphasis on secondary organic aerosols formation pathways. We evaluate the complex interplay between indigenous marine biogenic emissions, long-range transported pollutants, and episodic biomass burning. Emerging evidence indicates that the cloud condensation nuclei potential of Arctic OA is fundamentally governed by their molecular-level oxidation state and phase state, which collectively reshape cloud microphysics and radiative forcing. This synthesis underscores the necessity of integrating multiphase chemistry into the aerosol-cloud climate feedback loop to bolster the reliability of climate models in the context of rapid Arctic amplification.