Experiments on the Resistance of a Large Transport Vessel Navigating in the Arctic Region in Pack Ice Conditions

In this study, we carried out model tests to investigate the ice failure process and the resistance experienced by a transport vessel navigating in the Arctic region in pack ice conditions. We tested different navigation velocities, ice plate sizes, and ice concentrations. During the tests, we closely observed several phenomena, including the modes of interaction of the ice ship and the moving and failure modes of ice. We also measured the vessel resistances under different conditions. The test results indicate that the navigation velocity is a significant determinant of the moving and failure modes of ice. Moreover, vessel resistance is remarkably dependent on the ice concentration and navigation velocity. The variances of the mean and maximum resistance are also compared and discussed in detail.

Seismicity,structure and tectonics in the Arctic region

The "Arctic" region,where the North Pole occupies the center of the Arctic Ocean,has been affecting the environmental variation of the Earth from geological time to the present.However,the seismic activities in the area are not adequately monitored.Therefore,by conducting long term monitoring of seismic phenomenon as sustainable parameters,our understanding of both the tectonic evolution of the Earth and the dynamic interaction between the cryosphere and geosphere in surface layers of the Earth will increase.In this paper,the association of the seismicity and structure of the Arctic region,particularly focused on Eurasian continent and surrounding oceans,and its relationship with regional evolution during the Earth’s history is studied.The target areas cover representative tectonic provinces in the Eurasian Arctic,such as the wide area of Siberia,Baikal Rift Zone.Far East Russia,Arctic Ocean together with Greenland and Northern Canada.Based on discussion including characteristics of seismicity,heterogeneous structure of the crust and upper mantle,tectonic history and recent dynamic features of the Earth’s surface in the Arctic are summarized.

On the Governance of the Arctic Region under the Tragedy of the Commons

Because of global climate change,the natural environment is rapidly changing in the Arctic.The large amount of sea ice melting in the Arctic can lead to a great increase in the use of the world’s natural resources.This thesis focuses on the exploration and utilization of public waters in the Arctic region based on the economic theory of the Tragedy of the Commons,analyzes the current situation of Arctic governance,and predicts potential problems in the Arctic region,mainly including overfishing and environmental problems caused by coal and natural gas exploitation.Additionally,it makes an in-depth analysis on the current Arctic governance model based on the Arctic Council,and finally proposes some countermeasures and suggestions for Arctic governance.

Evolutionary characteristics of export trade network in the Arctic region

The economic potential induced by environmental changes in the Arctic region garnered substantial interest,which positions Arctic trade as a crucial indicator in forecasting the impacts of climate change on the global economy.Nevertheless,attention devoted to the evolving dynamics of trade in the Arctic region remains scarce.In this study,we constructed export trade network in the Arctic region(including Denmark,Finland,Sweden,Norway,Iceland,the Canadian Arctic,the Russian Arctic,Alaska State of the USA,and Greenland)from 1990 to 2019 and analyzed its topology and evolutionary characteristics through complex network theory.We used a structural entropy index based on the distribution of the number of trading partners and the degree of trade concentration to assess export diversity,while we also utilized a revealed comparative advantage index to evaluate product export competitiveness using the share of trade volume of each type of product.The results indicate that the total export trade in the Arctic region increased by 53.4%during 1990-2019,with the most significant growth observed in the exports of chemical products and mineral fuels.The increasing complexity of trade network in the Arctic region resulted in the region’s export destinations no longer being concentrated on a few major countries and regions.The proportion of exports from the Arctic region to Europe decreased by 13.5%,while the proportion of exports from the Arctic region to Asia and North America increased by 6.8%and 3.1%,respectively.The Arctic region exhibited clear distinctions in the range of flows of different products,and its export trade was becoming increasingly diversified.Although differences in comparative advantages between products within individual countries or regions have narrowed,substantial gaps persist.The findings of this study can enhance the comprehensive understanding of the significance and function of Arctic trade activities within the global economy,providing a scientific basis for addressing the associated challenges and opportunities in the context of climate change.

Mechanism and effects of the increase in winter temperatures in the Arctic region on cold winters in Heilongjiang Province,Northeast China for the period 1961-2018

With the advent of climate change,winter temperatures have been steadily increasing in the middle-to-high latitudes of the world.However,we have not found a corresponding decrease in the number of extremely cold winters.This paper,based on Climatic Research Unit(CRU)re-analysis data,and methods of trend analysis,mutation analysis,correlation analysis,reports on the effects of Arctic warming on winter temperatures in Heilongjiang Province,Northeast China.The results show that:(1)during the period 1961-2018,winter temperatures in the Arctic increased considerably,that is,3.5 times those of the Equator,which has led to an increasing temperature gradient between the Arctic and the Equator.An abrupt change in winter temperatures in the Arctic was observed in 2000.(2)Due to the global warming,an extremely significant warming occurred in Heilongjiang in winter,in particular,after the Arctic mutation in 2000,although there were two warm winters,more cold winters were observed and the interannual variability of winter temperature also increased.(3)Affected by the warming trend in the Arctic,the Siberian High has intensified,and both the Arctic Vortex and the Eurasian Zonal Circulation Index has weakened.This explains the decrease in winter temperatures in Heilongjiang,and why cold winters still dominate.Moreover,the increase in temperature difference between the Arctic and the Equator is another reason for the decrease in winter temperatures in Heilongjiang.

Status of persistent organic pollutants and heavy metals in surface water of Arctic region

Trace pollutants in the surface water of the Arctic region have been analyzed by the capillary gas chro-matography with the micro-electron capture detector (GC- mECD), the gas chromatography-mass spectrometry (GC- MS) and the inductively coupled plasmas-mass spectrometry (ICP-MS). Compared with previously reported studies, concentrations of OCPs in these regions are much lower than those in the last decades. The ratio of a-/g-HCH indicates the different pesticide composition between these two regions and is the potential marker for the source of the OCPs. Many other OCPs with different residue patterns have also been found for the first time in the two regions. No heavy metal contaminant was found in the investigation regions.

A coupled regional Arctic sea ice-ocean model:configuration and application

A regional sea ice-ocean coupled model for the Arctic Ocean was developed, based on the MlTgcm ocean circulation model and classical Hibler79 type two category thermodynamics-dynamics sea ice model.The sea ice dynamics and thermodynamics were considered based on Viscous-Plastic（VP） and Winton three-layer models,respectively.A detailed configuration of coupled model has been introduced.Special attention has been paid to the model grid setup,subgrid paramerization,ice-ocean coupling and open boundary treatment.The coupled model was then applied and two test run examples were presented.The first model run was a climatology simulation with 10 years（1992—2002） averaged NCAR/NCEP reanalysis data as atmospheric forcing.The second model run was a seasonal simulation for the period of 1992—2007.The atmospheric forcing was daily NCAR/NCEP reanalysis.The climatology simulation captured the general pattern of the sea ice thickness distribution of the Arctic,i.e.,the thickest sea ice is situated around the Canada Archipelago and the north coast of the Greenland. For the second model run,the modeled September Sea ice extent anomaly from 1992—2007 was highly correlated with the observations,with a linear correlation coefficient of 0.88.The minimum of the Arctic sea ice area in the September of 2007 was unprecedented.The modeled sea ice area and extent for this minimum was overestimated relative to the observations.However,it captured the general pattern of the sea ice retreat.

Atmospheric feedbacks on Arctic summer sea-ice anomalies in ensemble simulations of a coupled regional climate model

Ensemble simulations with the Arctic coupled regional climate model HIRHAM-NAOSIM have been analyzed to investigate atmospheric feedbacks to September sea-ice anomalies in the Arctic in autumn and the following winter. Different ＂low- minus high ice＂ composites have been calculated using selected model runs and different periods. This approach allows us to investigate the robustness of the simulated regional atmospheric feedbacks to detected sea-ice anomalies. Since the position and strength of the September sea-ice anomaly varies between the different ＂low- minus high ice＂ composites, the related simulated atmospheric patterns in autumn differ depending on the specific surface heat flux forcing through the oceaaa-atmosphere interface. However, irrespective of those autumn differences, the regional atmospheric feedback in the following winter is rather insensitive to the applied compositing. Neither the selection of simulations nor the considered period impacts the results. The simulated consistent large-scale atmospheric circulation pattern show-s a wave-like pattern with positive pressure anomaly over the region of the Barents/Kara Seas and Scandinavia/western Russia （＂Scandinavian-Ural blocking＂） and negative pressure anomaly over the East Siberian/Laptev Seas.

Regional disparities of phytoplankton in relation to environmental factors in the western Arctic Ocean during summer of 2010

Global warming has caused Arctic sea ice to rapidly retreat,which is affecting phytoplankton,the primary producers at the base of the food chain,as well as the entire ecosystem.However,few studies with large spatial scales related to the Arctic Basin at high latitude have been conducted.This study aimed to investigate the relationship between changes in phytoplankton community structure and ice conditions.Fifty surface and 41 vertically stratified water samples from the western Arctic Ocean（67.0°–88°26′N,152°–178°54′W） were collected by the Chinese icebreaker R/V Xuelong from July 20 to August 30,2010 during China＇s fourth Arctic expedition.Using these samples,the species composition,spatial distribution,and regional disparities of phytoplankton during different stages of ice melt were assessed.A total of 157 phytoplankton taxa（〉5 μm） belonging to 69 genera were identified in the study area.The most abundant species were Navicula pelagica and Thalassiosira nordenskioeldii,accounting for 31.23% and 14.12% of the total phytoplankton abundance,respectively.The average abundance during the departure trip and the return trip were 797.07×10~2 cells/L and 84.94×10~2 cells/L,respectively.The highest abundance was observed at Sta.R09 in the north of Herald Shoal,where Navicula pelagica was the dominant species accounting for 59.42% of the abundance.The vertical distribution of phytoplankton abundance displayed regional differences,and the maximum abundances were confined to the lower layers of the euphotic zone near the layers of the halocline,thermocline,and nutricline.The species abundance of phytoplankton decreased from the low-latitude shelf to the high-latitude basin on both the departure and return trips.The phytoplankton community structure in the shallow continental shelf changed markedly during different stages of ice melt,and there was shift in dominant species from centric to pennate diatoms.Results of canonical correspondence analysis（CCA） showed that there were two distinct communities of phytoplankton in the western Arctic Ocean,and water temperature,ice coverage and silicate concentration were the most important environmental factors affecting phytoplankton distribution in the surveyed sea.These findings will help predict the responses of phytoplankton to the rapid melting of Arctic sea ice.

利用重磁资料研究北极地区格陵兰-冰岛-法罗脊构造特征

为了深入研究北极地区格陵兰-冰岛-法罗脊及邻区的重磁场及构造特征,系统分析与整理了全球重力数据库V29数据、船测重力异常数据、全球地磁异常网格第3版数据以及航空磁测数据。利用变纬度化磁极方法得到磁力化极异常,进而利用位场边缘识别方法进行位场边缘识别,基于滑动平均法计算自由空间重力和磁力化极局部异常。结合已有的研究成果,深入分析格陵兰-冰岛-法罗脊及邻区的区域断裂构造格架,识别了7组主要断裂。这7组断裂在控制隆坳格架、基底结构与性质方面发挥了重要作用。基于这些主要断裂,划分了格陵兰板块、Kolbeinsey脊、扬马延微陆块、东扬马延深海盆地、格陵兰-冰岛-法罗复杂构造带、Rekjanes脊、Aegir脊和法罗-梅恩兰构造带共8个构造单元,为北极地区的地质勘探提供地质及地球物理资料。

美国涉北极地区的情报工作:政策背景、实施路径和保障体系

[研究目的]北极地区已成为全球关注的重点和大国竞争的舞台,美国兼具全球霸主和北极国家双重身份,研究其北极地区情报工作的建设和进展,为我国今后北极事务的开展提供借鉴。[研究方法]通过对美国官方发布的北极战略文件和相关媒体的报道进行分析,阐明其涉北极情报工作的宏观政策背景和具体实施路径。[研究结论]美国已将北极地区纳入其战略竞争框架,情报工作将发挥重要支撑作用。美国以“北极态势感知”为核心理念和建设目标,通过北极态势觉察、北极态势理解、北极态势预测三个子系统推动情报工作开展。同时,在情报工作的保障体系上,美国将从基础建设、运行机制和国际合作三个方面助推北极地区情报工作。为更好应对北极地区的竞争和博弈,我国应重视北极地区情报价值,对内提高能力建设,对外加强信息交流,以此推动中国特色的北极战略部署。

碳中和背景下北极低温经济发展的潜力和挑战

全球性气候问题攸关世界经济发展,实现碳中和目标不仅是可持续发展的必然选择,更是全球大势所趋。在此背景下,积极探索新的碳减排路径至关重要。全球性气候变暖影响具有显著的区域性差异,已有研究表明全球气候变暖对低温地区具有一定积极作用,经济发展最适宜区域正逐渐向高纬度地区转移。同时,低温地区特别是北极地区的碳减排潜力越发凸显,这一新形势也为碳中和目标实现和缓解气候变暖提供了新的发展方向。在阐释低温经济的概念和内涵的基础上,聚焦北极航运、建筑能耗、全球能源与信息互联网络、数据中心等在北极地区具有碳减排潜力的产业,分析北极低温经济发展的潜力和挑战。

Advances in Chinese Arctic and subarctic research in marine biology and ecology with emphasis on the Pacific Arctic sector

The Arctic is one of the most sensitive regions that respond through feedback to global climate changes. Climatic, hydrological and ecological changes in the Arctic are clear evidence of global warming. In 2012 and 2014, the 5th and 6th Chinese National Arctic Research Expeditions undertook studies in the Bering Sea, the Arctic Ocean （including the Chukchi Sea）, and the Norwegian Sea. These studies provided us with a better understanding of the marine biology and ecology in the Arctic and subarctic regions, particularly in the Pacific Arctic sector. Rapid changes observed in the Arctic environment include the shrinking of cold-water masses in the Bering Sea in the summer, and elevated water temperatures promoting phytoplankton blooms, leading to an increase in phytoplankton transferred to higher trophic levels. As a result, the transfer efficiency of organic matter toward the bottom weakened, leading to a reduction in benthic biomass. This is consistent with expectations that the overall carbon and energy flux will ultimately switch from the dominant mode of sea ice-algae-benthos to one of phytoplankton-zooplankton. Influenced by Pacific water inflow, fluvial runoff and melting sea ice, the Chukchi Sea exhibited different responses to various environmental changes. Interactions between water masses led to other interannual ecological shifts. With the increase in sea ice melt and sunlight in the central region of the Arctic Ocean, the relative abundance of heterotrophic bacteria is expected to increase, and play a vital role in the Arctic microbial loop.

Summertime CO_2 fluxes from tundra of Ny-?lesund in the High Arctic

The Arctic ecosystem, especially High Arctic tundra, plays a unique role in the global carbon cycle because of amplified warming in the region. However, relatively little research has been conducted in High Arctic tundra compared with other global ecosystems. In the present work, summertime net ecosystem exchange （NEE）, ecosystem respiration （ER）, and photosynthesis were investigated at six tundra sites （DM1-DM6） on Ny-A.lesund in the High Arctic. NEE at the tundra sites varied between a weak sink and strong source （-3.3 to 19.0 mg CO2·m-2.h-1）. ER and gross photosynthesis were 42.8 to 92.9 mg CO2·m-2·h-1 and 54.7 to 108.7 mg CO2·m-2·h-1, respectively. The NEE variations showed a significant correlation with photosynthesis rates, whereas no significant correlation was found with ecosystem respiration, indicating that NEE variations across the region were controlled by differences in net uptake of CO2 owing to photosynthesis, rather than by variations in ER. A Qm value of 1.80 indicated weak temperature sensitivity of tundra ER and its response to future global warming. NEE and gross photosynthesis also showed relatively strong correlations with C/N ratio. The tundra ER, NEE, and gross photosynthesis showed variations over slightly waterlogged wetland tundra, mesic and dry tundra. Overall, soil temperature, nutrients and moisture can be key effects on CO2 fluxes, ecosystem respiration, and NEE in the High Arctic.

北极地区油气资源分布特征与开发利用分析

北极地区蕴藏着丰富的油气资源,对优化我国能源进口结构及有效分散石油进口风险具有重要意义。基于标普全球和美国地质调查局最新数据,本文开展了环北极主要国家油气勘探开发历程分析和北极地区油气资源时空分布特征分析。分析结果表明:(1)北极地区油气勘探开发工作主要在俄罗斯、美国、加拿大、挪威和丹麦五国开展,分为早期调查(至1963年)、陆上大发现和早期开发(1964-1976年)、海陆并进和快速上产(1977-1992年)、勘探低迷和开发高位徘徊(1993年至今)4个阶段。(2)北极地区已发现油气田519个,累计油气探明和控制可采储量474亿吨油当量,累计产量162亿吨油当量,待发现资源量1159亿吨油当量,呈现出油气构成不均、海陆分布不均、国别分布不均和层位分布不均的特点。基于对环北极国家油气开发利用情况和前景的综合考量,建议我国积极与俄罗斯开展天然气勘探开发合作,在夯实管道天然气开发建设进程的基础上,拓展液化天然气和北极航道基础设施建设合作领域。

基于我国CMIP6模式的北极海冰厚度比较及评价

本文选取了第六次国际耦合模式比较计划(CMIP6)中的8个中国地球气候系统模式,将这些模式的北极海冰厚度与华盛顿大学的PIOMAS海冰厚度同化产品进行对比,评估了所选模式1980-2014年北极海冰厚度多年平均空间分布和长期趋势,并通过泰勒评分法对各模式的模拟能力进行了量化。结果表明,无论3月还是9月,所有模式均与PIOMAS存在差异,偏差位置主要集中在格陵兰岛北部、巴伦支海、白令海峡附近。模式均低估北极3月和9月海冰中心区域厚度,此外还普遍高估3月海冰边缘区厚度。其中空间分布与PIOMAS最为相近的模式为FIO-ESM-2-0,其次为FGOALS-f3-L模式。海冰厚度的长期趋势表明,海冰厚度整体呈下降趋势,并且9月的下降程度明显大于3月,与PIOMAS长期趋势空间分布最为相似的模式为NESM3。在此基础上,本文进一步对比了82°N以北3种大气再分析资料、1种卫星观测产品与8个CMIP6模式的辐射分量,再分析资料及模式间辐射分量有很大的差别,其中有两个模式的辐射存在明显的异常, FGOALS-f3-L模式3月上行短波辐射和CIESM模式9月上行短波辐射严重偏小,这可能是由于模式模拟存在误差。

地缘背景下俄属北极圈内中俄不可再生资源合作

俄罗斯拥有丰富的资源,能源种类多样,北极圈内蕴藏巨大的石油、天然气等不可再生资源,俄罗斯的地缘战略地位格外突出。21世纪以来,中国经济快速发展,石油、天然气等非再生资源的需求越来越大,我国成为世界主要能源消费大国。在地缘背景下,中俄在北极地区的油气合作成为两国北极战略的外部支柱,两国不断发挥各自比较优势,各取所需,实现北极能源经济的优势互补。有必要明确中俄北极油气资源合作基础,分析中俄北极油气资源合作现状,探索中俄北极油气资源合作路径,最终实现互利共赢。

Lessons and prospects of Sino-Russian Arctic cooperation

The strategic partnership between China and Russia is creating solid ground for the cooperative development of the Arctic. These two states＇ joint development of the Northern Sea Route will not only provide additional impulse to the export- oriented economy of China and allow further diversification of supply routes to China, but will also promote investment into the infrastructure and economic growth of Russian northern territories. Climate change in the Arctic has forced China and Russia to acknowledge the sustainable use of the Arctic. On the one hand, exploration of the region should not harm indigenous people＇s rights and should help this population improve their standard of living by providing qualified healthcare and opportunities for commercial fulfillment of traditional crafts. On the other hand, this exploration should also include elimination of harmful anthropogenic impact and provide support for environment self-restoration. Sino-Russian Arctic cooperation will help humans discover eco-friendly approaches to use Arctic resources, promote rational use of the Arctic and inspire sustainable development of the region.

Changing Spring Phenology Dates in the Three-Rivers Headwater Region of the Tibetan Plateau during 1960–2013

The variation of the vegetation growing season in the Three-Rivers Headwater Region of the Tibetan Plateau has recently become a controversial topic. One issue is that the estimated local trend in the start of the vegetation growing season(SOS)based on remote sensing data is easily affected by outliers because this data series is short. In this study, we determine that the spring minimum temperature is the most influential factor for SOS. The significant negative linear relationship between the two variables in the region is evaluated using Moderate Resolution Imaging Spectroradiometer–Normalized Difference Vegetation Index data for 2000–13. We then reconstruct the SOS time series based on the temperature data for 1960–2013.The regional mean SOS shows an advancing trend of 1.42 d(10 yr)during 1960–2013, with the SOS occurring on the 160th and 151st days in 1960 and 2013, respectively. The advancing trend enhances to 6.04 d(10 yr)during the past 14 years. The spatiotemporal variations of the reconstructed SOS data are similar to those deduced from remote sensing data during the past 14 years. The latter exhibit an even larger regional mean trend of SOS [7.98 d(10 yr)] during 2000–13. The Arctic Oscillation is found to have significantly influenced the changing SOS, especially for the eastern part of the region,during 2000–13.

我国极地救援体系建设探讨

极地恶劣的自然环境和特殊的地理位置,使极地活动具有较高的风险性,而频发的突发意外事故,对极地区域的应急救援提出了更高要求。我国在南极和北极开展了大量的科学考察、商业航运等活动,但在极地救援方面的基础十分薄弱。该文通过梳理极地现有的主流救援模式,提出极地救援体系的初步构想,并从组织架构、法规研究、平台搭建、环境勘测、通信导航、站点布局、装备发展、人才培养和规程制定等方面予以阐述说明,填补我国在极地救援体系研究方面的空白,以期为今后极地救援体系的建设提供参考和借鉴。