Polar Science最新文献_第7页

Seasonal habitat use of ringed seals in the Thule area, northwestern Greenland 格陵兰西北部图勒地区环斑海豹季节性栖息地利用情况

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101145

Yuta Sakuragi , Aqqalu Rosing-Asvid , Shin Sugiyama , Yoko Mitani

Recent rapid environmental changes along the Greenland coast have significantly impacted Arctic marine mammals. The melting of tidewater glaciers influences ocean environments and ecosystems, potentially changing the distribution and behavior of Arctic marine mammals. The ringed seal (Pusa hispida) is a keystone species in the Arctic marine ecosystem. In this study, four ringed seals were equipped with Argos conductivity-temperature-depth (CTD) satellite relay data loggers close to tidewater glaciers in the Thule area of northwestern Greenland to investigate the relationship between their behavior and the marine environment. All seals spent most of their time in the vicinity of tidewater glacier fronts during the open-water period. After that period, the two seals moved out of the glacial fjords due to the formation of land-fast ice and stayed in the North Water Polynya area, where sea ice was relatively thin and sparse during the ice-covered period. Furthermore, CTD data suggest that ringed seals mainly dove to the depths of the water inhabited by the polar cod (Boreogadus saida). These habitat use characteristics, associated with distribution of ice and prey species, could potentially affect the distribution and ecology of this species under future climate change.

最近格陵兰海岸的快速环境变化对北极海洋哺乳动物产生了重大影响。潮汐冰川的融化影响海洋环境和生态系统，可能改变北极海洋哺乳动物的分布和行为。环斑海豹（Pusa hispida）是北极海洋生态系统的关键物种。在这项研究中，在格陵兰西北部图勒地区的潮汐冰川附近，为4只环海豹配备了Argos电导率-温度-深度（CTD）卫星中继数据记录器，以研究它们的行为与海洋环境之间的关系。在开放水域期间，所有的海豹大部分时间都呆在潮汐冰川前沿附近。在此之后，由于陆固冰的形成，这两只海豹离开了冰川峡湾，留在了北水峡地区，在冰覆盖时期，那里的海冰相对较薄且稀疏。此外，CTD数据表明环斑海豹主要潜入极地鳕鱼（Boreogadus saida）居住的水域深处。这些栖息地利用特征与冰和猎物物种的分布有关，可能会影响该物种在未来气候变化下的分布和生态。

{"title":"Seasonal habitat use of ringed seals in the Thule area, northwestern Greenland","authors":"Yuta Sakuragi , Aqqalu Rosing-Asvid , Shin Sugiyama , Yoko Mitani","doi":"10.1016/j.polar.2024.101145","DOIUrl":"10.1016/j.polar.2024.101145","url":null,"abstract":"<div><div>Recent rapid environmental changes along the Greenland coast have significantly impacted Arctic marine mammals. The melting of tidewater glaciers influences ocean environments and ecosystems, potentially changing the distribution and behavior of Arctic marine mammals. The ringed seal (<em>Pusa hispida</em>) is a keystone species in the Arctic marine ecosystem. In this study, four ringed seals were equipped with Argos conductivity-temperature-depth (CTD) satellite relay data loggers close to tidewater glaciers in the Thule area of northwestern Greenland to investigate the relationship between their behavior and the marine environment. All seals spent most of their time in the vicinity of tidewater glacier fronts during the open-water period. After that period, the two seals moved out of the glacial fjords due to the formation of land-fast ice and stayed in the North Water Polynya area, where sea ice was relatively thin and sparse during the ice-covered period. Furthermore, CTD data suggest that ringed seals mainly dove to the depths of the water inhabited by the polar cod (<em>Boreogadus saida</em>). These habitat use characteristics, associated with distribution of ice and prey species, could potentially affect the distribution and ecology of this species under future climate change.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101145"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An investigation into oil spill dynamics affected by floe-like obstacles with various distributions 不同分布的浮状障碍物对溢油动力学影响的研究

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2025.101168

Motomu Oyama , Akihisa Konno , Takatoshi Matsuzawa

This study investigates the spreading behavior of oil spills under simulated Arctic sea ice conditions with varying concentrations below 60%. Experiments were conducted in a controlled environment using PVC pipes to mimic sea ice obstacles at concentrations of 13.4%, 26.7%, and 53.4%. Results showed that at lower concentrations, oil spreading isotropically in a circular pattern, while at the highest concentration, the spreading became anisotropic, forming a diamond shape influenced by the obstacle arrangement. Contrary to conventional numerical models that assume decreased diffusion rates with increased ice concentration, the findings suggest that the diffusion rate can increase at higher concentrations due to the spatial arrangement of obstacles. The study also highlights the predominant role of surface tension in driving oil spreading when the oil thickness is below 2 mm. These insights call for refinements in current models of oil spill behavior in ice-covered waters, emphasizing the need to consider both obstacle arrangement and interfacial dynamics for better spill prediction and management in Arctic regions.

本研究调查了在不同浓度低于60%的模拟北极海冰条件下石油泄漏的扩散行为。实验在受控环境中进行，使用PVC管模拟海冰障碍物，浓度分别为13.4%、26.7%和53.4%。结果表明：低浓度时，原油呈各向同性圆形扩散；高浓度时，原油呈各向异性扩散，受障碍物排列影响形成菱形扩散；与传统的数值模型假设扩散速率随冰浓度的增加而降低相反，研究结果表明，由于障碍物的空间排列，扩散速率可以在较高浓度下增加。研究还表明，当油厚小于2 mm时，表面张力对油扩散起主导作用。这些见解要求对现有的冰覆盖水域溢油行为模型进行改进，强调需要考虑障碍物布置和界面动力学，以便更好地预测和管理北极地区的溢油。

{"title":"An investigation into oil spill dynamics affected by floe-like obstacles with various distributions","authors":"Motomu Oyama , Akihisa Konno , Takatoshi Matsuzawa","doi":"10.1016/j.polar.2025.101168","DOIUrl":"10.1016/j.polar.2025.101168","url":null,"abstract":"<div><div>This study investigates the spreading behavior of oil spills under simulated Arctic sea ice conditions with varying concentrations below 60%. Experiments were conducted in a controlled environment using PVC pipes to mimic sea ice obstacles at concentrations of 13.4%, 26.7%, and 53.4%. Results showed that at lower concentrations, oil spreading isotropically in a circular pattern, while at the highest concentration, the spreading became anisotropic, forming a diamond shape influenced by the obstacle arrangement. Contrary to conventional numerical models that assume decreased diffusion rates with increased ice concentration, the findings suggest that the diffusion rate can increase at higher concentrations due to the spatial arrangement of obstacles. The study also highlights the predominant role of surface tension in driving oil spreading when the oil thickness is below 2 mm. These insights call for refinements in current models of oil spill behavior in ice-covered waters, emphasizing the need to consider both obstacle arrangement and interfacial dynamics for better spill prediction and management in Arctic regions.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101168"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Gravity strike angles from EIGEN6C4 to seek conditions favourable for hydrocarbon occurrences in the Arctic zone 利用本征6c4的重力走向角寻找北极地区有利油气赋存的条件

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101157

Jaroslav Klokočník , Jan Kostelecký , Aleš Bezděk

An unusual remote sensing method is employed to seek for the sedimentary areas with possible deposits of oil/gas. The gravity aspects, derived from the global high-resolution gravity field model EIGEN 6C4, namely the strike angles, are used to detect zones on land and off-shore with a higher probability of occurrences of hydrocarbons in the Arctic zone. We utilize our previous experience with the gravity aspects applied for various geological features on the Earth, the Moon, and Mars (everywhere there our knowledge of the gravity field parameters for the respective planet is already sufficient for such a task). The West Siberian basin and Yamal peninsula nearby with known and huge oil/gas resources are used as a test bed demonstrating how our method works. Then, we extrapolate to the Lomonosov Ridge in the Arctic Ocean (till now only with scientific drilling), showing the most promising localities with possible hydrocarbon occurrences. Our results can also be used for speculations about many further untapped places in the Arctic zone with prospective hydrocarbon resources.

采用一种不同寻常的遥感方法寻找可能有油气沉积的沉积区域。重力方面，来自全球高分辨率重力场模型EIGEN 6C4，即走向角，用于探测北极地区陆地和海上碳氢化合物出现可能性较高的区域。我们利用我们以前在地球、月球和火星的各种地质特征上应用重力方面的经验（在那里，我们对各自行星的重力场参数的知识已经足以完成这样的任务）。西西伯利亚盆地和亚马尔半岛附近已知的巨大油气资源被用作试验平台，展示了我们的方法是如何工作的。然后，我们推断到北冰洋的罗蒙诺索夫海岭（到目前为止只有科学钻探），显示了最有希望发现碳氢化合物的地方。我们的结果也可以用来推测北极地区许多未开发的有潜在碳氢化合物资源的地方。

{"title":"Gravity strike angles from EIGEN6C4 to seek conditions favourable for hydrocarbon occurrences in the Arctic zone","authors":"Jaroslav Klokočník , Jan Kostelecký , Aleš Bezděk","doi":"10.1016/j.polar.2024.101157","DOIUrl":"10.1016/j.polar.2024.101157","url":null,"abstract":"<div><div>An unusual remote sensing method is employed to seek for the sedimentary areas with possible deposits of oil/gas. The gravity aspects, derived from the global high-resolution gravity field model EIGEN 6C4, namely the strike angles, are used to detect zones on land and off-shore with a higher probability of occurrences of hydrocarbons in the Arctic zone. We utilize our previous experience with the gravity aspects applied for various geological features on the Earth, the Moon, and Mars (everywhere there our knowledge of the gravity field parameters for the respective planet is already sufficient for such a task). The West Siberian basin and Yamal peninsula nearby with known and huge oil/gas resources are used as a test bed demonstrating how our method works. Then, we extrapolate to the Lomonosov Ridge in the Arctic Ocean (till now only with scientific drilling), showing the most promising localities with possible hydrocarbon occurrences. Our results can also be used for speculations about many further untapped places in the Arctic zone with prospective hydrocarbon resources.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101157"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Particle size distribution of ice chips produced under varies drilling conditions in the process of ice core drilling 冰芯钻探过程中不同钻探条件下产生的冰屑的粒度分布

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101136

Xinyu Lv , Zhihao Cui , Ting Wang , Yumin Wen , Rusheng Wang

The particle size of ice chips has a significant influence on the efficiency of the transportation of ice chips, the maximum possible rate of penetration, and eventually determines the success or failure of drilling. To determine the factors that affect the particle size of ice chips and elucidate the impact mechanism of the factors on the particle size of ice chips, an ice cutting test stand was built, the ice chips produced under different drilling conditions are sampled using the cutter with straight cutting edge and full kerf width, and the distribution of particle size of ice chips under various drilling conditions was obtained by screening and weighing methods. Finally, the influencing factors and laws on the distribution of particle size of ice chips were determined. The rake and relief angles of the cutter affect mainly the proportion of ice chips with particle sizes smaller than 0.5 mm. As the rake angle and the relief angle of the cutter increases, the proportion of ice chips with a particle size of smaller than 0.5 mm increases. The rotation speed of the drill bit and cutting depth have an impact on the overall distribution of particle size of ice chips. As the rotation speed of the drill bit and cutting depth increase, the particle size of ice chips increases. But as the increase continues, the trend of increase gradually weakens.

冰屑的粒径大小对冰屑的输送效率、最大可能的钻进速率有显著影响，并最终决定钻井的成败。为确定影响冰屑粒度的因素，阐明各因素对冰屑粒度的影响机理，搭建了冰屑切割试验台，采用直刃、满刃的铣刀对不同钻孔条件下产生的冰屑进行取样，通过筛分、称重等方法获得了不同钻孔条件下冰屑粒度的分布情况。最后，确定了影响冰屑粒径分布的因素和规律。铣刀的前倾角和卸角主要影响粒径小于0.5 mm的冰屑的比例。随着切刀前倾角和卸角的增大，粒径小于0.5 mm的冰屑所占比例增大。钻头转速和切削深度对冰屑粒径的整体分布有影响。随着钻头转速的增加和切削深度的增加，冰屑的粒径增大。但随着增长的继续，增长趋势逐渐减弱。

{"title":"Particle size distribution of ice chips produced under varies drilling conditions in the process of ice core drilling","authors":"Xinyu Lv , Zhihao Cui , Ting Wang , Yumin Wen , Rusheng Wang","doi":"10.1016/j.polar.2024.101136","DOIUrl":"10.1016/j.polar.2024.101136","url":null,"abstract":"<div><div>The particle size of ice chips has a significant influence on the efficiency of the transportation of ice chips, the maximum possible rate of penetration, and eventually determines the success or failure of drilling. To determine the factors that affect the particle size of ice chips and elucidate the impact mechanism of the factors on the particle size of ice chips, an ice cutting test stand was built, the ice chips produced under different drilling conditions are sampled using the cutter with straight cutting edge and full kerf width, and the distribution of particle size of ice chips under various drilling conditions was obtained by screening and weighing methods. Finally, the influencing factors and laws on the distribution of particle size of ice chips were determined. The rake and relief angles of the cutter affect mainly the proportion of ice chips with particle sizes smaller than 0.5 mm. As the rake angle and the relief angle of the cutter increases, the proportion of ice chips with a particle size of smaller than 0.5 mm increases. The rotation speed of the drill bit and cutting depth have an impact on the overall distribution of particle size of ice chips. As the rotation speed of the drill bit and cutting depth increase, the particle size of ice chips increases. But as the increase continues, the trend of increase gradually weakens.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101136"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nutrient dynamics and biogeochemical processes at the Polar front of Indian sector of the Southern Ocean: Influence of Circumpolar deep water intrusion 南大洋印度板块极地锋的营养动态和生物地球化学过程：环极深水入侵的影响

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101130

Melena A. Soares , R.K. Mishra , P. Sabu , V. Venkataramana , R.K. Naik , A. Sarkar , R. Chacko , N. Anilkumar

The Circumpolar Deep water (CDW) is one of the largest water masses in the Southern Ocean. The cross-frontal flow of the CDW is a vital mode of redistribution and transport of heat, salts, nutrients, etc. in the ocean. The present study aims to understand the role of the CDW intrusion on nutrient dynamics and biogeochemical processes at the Polar frontal region. The study noted a patch of high nutrients layer at ∼300–400 m in the Polar Front-II, underlying the dicothermal layer or the temperature minimum layer. This high nutrient patch was attributed to the intrusion of the CDW at the Polar front, influencing the physico-chemical processes in the water column. It was evident that, the density gradient, stratification and overall, the combined effect of physico-chemical and biological factors as a consequence of intrusion of the CDW contributed to the formation of the high nitrate patch at the Polar Front-II. Even though, the CDW intrusion did not significantly impact the photic layer dynamics during this study, the possible barrier effect during austral summer contribute to the formation of the high nitrate layer. This feature may be responsible for trapping nutrients in the subsurface due to stratification, and made available to the photic region via upwelling processes, consequently triggering changes in the biological community structure and biogeochemical processes.

环极深水（CDW）是南大洋最大的水团之一。CDW的横锋流是海洋中热量、盐、营养物质等再分配和运输的重要方式。本研究旨在了解CDW入侵对极地锋区营养动态和生物地球化学过程的影响。该研究指出，在极地锋- ii的约300-400米处有一块高营养层，位于双温层或最低温度层之下。这一高营养物斑块是由于极地锋的CDW入侵，影响了水柱的物理化学过程。结果表明，由于CDW的入侵，密度梯度、分层和总体上物理化学和生物因素的综合作用促成了极锋高硝酸盐斑块的形成。尽管在本研究中，CDW入侵对光层动态没有显著影响，但南方夏季可能存在的屏障效应有助于高硝酸盐层的形成。这一特征可能是由于分层作用而将营养物质困在地下，并通过上升流过程进入光区，从而引发生物群落结构和生物地球化学过程的变化。

{"title":"Nutrient dynamics and biogeochemical processes at the Polar front of Indian sector of the Southern Ocean: Influence of Circumpolar deep water intrusion","authors":"Melena A. Soares , R.K. Mishra , P. Sabu , V. Venkataramana , R.K. Naik , A. Sarkar , R. Chacko , N. Anilkumar","doi":"10.1016/j.polar.2024.101130","DOIUrl":"10.1016/j.polar.2024.101130","url":null,"abstract":"<div><div>The Circumpolar Deep water (CDW) is one of the largest water masses in the Southern Ocean. The cross-frontal flow of the CDW is a vital mode of redistribution and transport of heat, salts, nutrients, etc. in the ocean. The present study aims to understand the role of the CDW intrusion on nutrient dynamics and biogeochemical processes at the Polar frontal region. The study noted a patch of high nutrients layer at ∼300–400 m in the Polar Front-II, underlying the dicothermal layer or the temperature minimum layer. This high nutrient patch was attributed to the intrusion of the CDW at the Polar front, influencing the physico-chemical processes in the water column. It was evident that, the density gradient, stratification and overall, the combined effect of physico-chemical and biological factors as a consequence of intrusion of the CDW contributed to the formation of the high nitrate patch at the Polar Front-II. Even though, the CDW intrusion did not significantly impact the photic layer dynamics during this study, the possible barrier effect during austral summer contribute to the formation of the high nitrate layer. This feature may be responsible for trapping nutrients in the subsurface due to stratification, and made available to the photic region via upwelling processes, consequently triggering changes in the biological community structure and biogeochemical processes.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101130"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spatial and temporal occurrence of two Gyrodinium species in the seasonal ice zone off Wilkes Land, Southern Ocean 南大洋威尔克斯陆附近季节性冰区两种 Gyrodinium 的时空分布情况

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2025.101169

Ryo Matsuda , Masayoshi Sano , Chiho Tsuchiya , Keigo D. Takahashi , Shintaro Takao , Kohei Mizobata , Masato Moteki , Ryosuke Makabe , Norio Kurosawa

Sea ice is crucial for regulating primary production and carbon export. Among sea ice-dwelling organisms, the genus Gyrodinium (Dinophyceae) are particularly significant, with their release into the water column influencing carbon flow in the lower food web. Specifically, G. rubrum and G. heterogrammum feed on phytoplankton and may contribute to carbon export, as their cells resemble fecal pellets. However, due to the challenges in quantifying Gyrodinium cells microscopically, the species-specific dynamics of these organisms remained unclear in the seasonal ice zone of the Southern Ocean. This study investigates the abundance of G. rubrum and G. heterogrammum in sea ice, seawater, and sinking particles using quantitative PCR analysis. Our results indicate that G. rubrum is widely distributed from coastal polynyas to continental slopes, whereas G. heterogrammum is confined to coastal areas. Sediment trap data showed G. rubrum flux at 60 m depth increased with sea ice melting. In contrast, G. heterogrammum fluxes at depths of 150 and 500 m were observed more frequently than those of G. rubrum, with no apparent correlation to sea ice melting. These findings suggest that G. rubrum distribution is closely linked to sea ice melt, whereas G. heterogrammum appears to be unaffected by such changes.

海冰对于调节初级生产和碳出口至关重要。在海冰生物中，陀螺藻属（Dinophyceae）尤为重要，它们释放到水柱中影响下层食物网的碳流。具体来说，G. rubrum和G. heterogramum以浮游植物为食，可能有助于碳输出，因为它们的细胞类似于粪便颗粒。然而，由于在显微镜下定量Gyrodinium细胞的挑战，这些生物在南大洋季节性冰带中的物种特异性动态尚不清楚。本研究采用定量PCR的方法，研究了海冰、海水和下沉颗粒中红藻和异藻的丰度。结果表明，红草属植物广泛分布于沿海多礁滩至大陆斜坡，而异草属植物仅局限于沿海地区。沉积物捕集器数据显示，60 m深度的G. rubrum通量随着海冰融化而增加。相比之下，在150和500 m深度观测到的异叶藻通量比红叶藻更频繁，与海冰融化没有明显的相关性。这些发现表明，红毛藻的分布与海冰融化密切相关，而异毛藻似乎不受这种变化的影响。

{"title":"Spatial and temporal occurrence of two Gyrodinium species in the seasonal ice zone off Wilkes Land, Southern Ocean","authors":"Ryo Matsuda , Masayoshi Sano , Chiho Tsuchiya , Keigo D. Takahashi , Shintaro Takao , Kohei Mizobata , Masato Moteki , Ryosuke Makabe , Norio Kurosawa","doi":"10.1016/j.polar.2025.101169","DOIUrl":"10.1016/j.polar.2025.101169","url":null,"abstract":"<div><div>Sea ice is crucial for regulating primary production and carbon export. Among sea ice-dwelling organisms, the genus <em>Gyrodinium</em> (Dinophyceae) are particularly significant, with their release into the water column influencing carbon flow in the lower food web. Specifically, <em>G. rubrum</em> and <em>G. heterogrammum</em> feed on phytoplankton and may contribute to carbon export, as their cells resemble fecal pellets. However, due to the challenges in quantifying <em>Gyrodinium</em> cells microscopically, the species-specific dynamics of these organisms remained unclear in the seasonal ice zone of the Southern Ocean. This study investigates the abundance of <em>G. rubrum</em> and <em>G. heterogrammum</em> in sea ice, seawater, and sinking particles using quantitative PCR analysis. Our results indicate that <em>G. rubrum</em> is widely distributed from coastal polynyas to continental slopes, whereas <em>G. heterogrammum</em> is confined to coastal areas. Sediment trap data showed <em>G. rubrum</em> flux at 60 m depth increased with sea ice melting. In contrast, <em>G. heterogrammum</em> fluxes at depths of 150 and 500 m were observed more frequently than those of <em>G. rubrum</em>, with no apparent correlation to sea ice melting. These findings suggest that <em>G. rubrum</em> distribution is closely linked to sea ice melt, whereas <em>G. heterogrammum</em> appears to be unaffected by such changes.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101169"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ice thickness inversion assessment: A comparison study for Waldemarbreen and Irenebreen glaciers, Svalbard 冰厚反演评价：斯瓦尔巴群岛Waldemarbreen和Irenebreen冰川的比较研究

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2025.101167

Lelde Švinka, Jānis Karušs, Kristaps Lamsters

Accurate ice thickness estimates are crucial for solving both glaciological and hydrological problems, and ice thickness inversion models are generally used to obtain these estimates. Several studies have assessed the accuracy of model inversions, however, usually the evaluation is done against a sparse set of field measurements. In this study, we employ the open-source models GlabTop2 and Open Global Glacier Model (OGGM) to estimate ice thickness and volume for the Waldemarbreen and Irenebreen glaciers (Svalbard archipelago), evaluating their accuracy against ground-penetrating radar (GPR) measurements. The results show that the ice thickness root-mean-square errors for GlabTop2 and OGGM are 28.5 and 13.9 m and the relative volume errors are 17.4 and 39.9%, respectively. Calibration of glacier shape factor slightly improves GlabTop2 results, however, this model tends to provide good average estimates but falls short on accurate spatial thickness distribution. On the contrary, the OGGM model is highly dependent on the chosen dataset for mass balance calibration and tends to provide better spatial distribution while performing worse regarding average thickness and overall glacier volume. Both inversion models present severe thickness errors among studied glaciers, implying the need for improvements in models and underlying theoretical assumptions that require continuous and extensive field measurements.

准确的冰厚估算对于解决冰川学和水文问题至关重要，通常使用冰厚反演模型来获得这些估算。一些研究已经评估了模型反演的准确性，然而，通常评估是针对稀疏的现场测量集进行的。在这项研究中，我们使用开源模型GlabTop2和开放全球冰川模型（OGGM）来估计瓦尔德马布林和Irenebreen冰川（斯瓦尔巴群岛）的冰厚和体积，并评估它们在探地雷达（GPR）测量下的精度。结果表明，GlabTop2和OGGM的冰厚均方根误差分别为28.5和13.9 m，相对体积误差分别为17.4和39.9%。冰川形状因子的校正略微改善了GlabTop2模型的结果，但该模型往往提供良好的平均估计，但在精确的空间厚度分布方面存在不足。相反，OGGM模型高度依赖于所选择的数据集进行质量平衡校准，并且倾向于提供更好的空间分布，而在平均厚度和总体冰川体积方面表现较差。这两种反演模式在所研究的冰川中都存在严重的厚度误差，这意味着需要改进模式和基础的理论假设，这些假设需要连续和广泛的实地测量。

{"title":"Ice thickness inversion assessment: A comparison study for Waldemarbreen and Irenebreen glaciers, Svalbard","authors":"Lelde Švinka, Jānis Karušs, Kristaps Lamsters","doi":"10.1016/j.polar.2025.101167","DOIUrl":"10.1016/j.polar.2025.101167","url":null,"abstract":"<div><div>Accurate ice thickness estimates are crucial for solving both glaciological and hydrological problems, and ice thickness inversion models are generally used to obtain these estimates. Several studies have assessed the accuracy of model inversions, however, usually the evaluation is done against a sparse set of field measurements. In this study, we employ the open-source models GlabTop2 and Open Global Glacier Model (OGGM) to estimate ice thickness and volume for the Waldemarbreen and Irenebreen glaciers (Svalbard archipelago), evaluating their accuracy against ground-penetrating radar (GPR) measurements. The results show that the ice thickness root-mean-square errors for GlabTop2 and OGGM are 28.5 and 13.9 m and the relative volume errors are 17.4 and 39.9%, respectively. Calibration of glacier shape factor slightly improves GlabTop2 results, however, this model tends to provide good average estimates but falls short on accurate spatial thickness distribution. On the contrary, the OGGM model is highly dependent on the chosen dataset for mass balance calibration and tends to provide better spatial distribution while performing worse regarding average thickness and overall glacier volume. Both inversion models present severe thickness errors among studied glaciers, implying the need for improvements in models and underlying theoretical assumptions that require continuous and extensive field measurements.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101167"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unpacking inclusivity of the Antarctic Treaty System amidst contemporary challenges 在当代挑战中揭示《南极条约体系》的包容性

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101144

Zia Madani

The Antarctic Treaty and its associated instruments, collectively known as the Antarctic Treaty System (ATS), face significant challenges, predominantly stemming from external sources. These challenges increasingly pressurize the effectiveness of the ATS. This article aims to assess these contemporary challenges in the context of inclusivity in the Antarctic Treaty and the ATS, underscoring the importance of broad international cooperation in governance and scientific endeavors. By revisiting the core principles of the ATS, and the stipulations relating to the inclusion of new participants in its key instruments, this study seeks to examine the diverse array of, not only, avenues and possibilities for broad participation, but also obstacles hindering such participation and cooperation within the ATS. Given the mounting global geopolitical tensions, it is pertinent and timely to question the continued suitability of the Antarctic Treaty and the ATS in maintaining the Antarctic as a natural reserve for peace and scientific research.

《南极条约》及其相关文书，统称为《南极条约系统》，面临着主要来自外部的重大挑战。这些挑战给ATS的有效性带来了越来越大的压力。本文旨在评估《南极条约》和ATS的包容性背景下的这些当代挑战，强调在治理和科学努力方面开展广泛国际合作的重要性。通过重新审视ATS的核心原则，以及与将新参与者纳入其关键文书有关的规定，本研究不仅试图审查广泛参与的各种途径和可能性，而且还试图审查阻碍此类参与和ATS内部合作的各种障碍。鉴于全球地缘政治紧张局势日益加剧，对《南极条约》和《南极贸易协定》是否继续适合维持南极作为和平与科学研究的自然保护区提出质疑是恰当和及时的。

引用次数: 0

Impact of atmospheric river evolutions on Greenland ice sheet mass changes over the last two decades, 2000–2019 2000-2019年过去二十年大气河流演变对格陵兰冰盖质量变化的影响

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101158

Jingming Li , Xinyu Qin , Wenhao Li , C.K. Shum , Fei Li , Shengkai Zhang

Atmospheric rivers (ARs) serve as mechanisms that transport water vapor to the poles, triggering extreme weather events, altering weather patterns over Greenland, and even impacting mass changes in the Greenland ice sheet. In this study, we detected and extracted ARs spatiotemporal evolution characteristics over Greenland from the past two decades. And subsequently analyzed the Greenland mass changes. Our findings indicate that between 2000 and 2019, the annual occurrences of ARs varied from 13 to 27 times, with durations ranging from 156 to 610 h. Interestingly, the ARs exhibited distinct migration patterns across different periods, transitioning from a uniform distribution towards the west side of Greenland and eventually towards the east side. To delve deeper into the relationship between ARs and mass changes, we assessed the contribution of ARs to Greenland's surface mass balance using a five-year study period. The results show that the contribution of AR to SMB has a tendency to increase in stages, 20.5% from 2000 to 2004, 31.5% from 2005 to 2009, 46.4% from 2010 to 2014, and 48.2% from 2015 to 2019.

大气河流（ARs）是将水蒸气输送到两极的机制，引发极端天气事件，改变格陵兰岛的天气模式，甚至影响格陵兰冰盖的质量变化。在这项研究中，我们检测并提取了格陵兰岛近20年的ARs时空演变特征。随后分析了格陵兰岛的质量变化。我们的研究结果表明，在2000年至2019年期间，ar的年发生率从13到27次不等，持续时间从156到610小时不等。有趣的是，ar在不同时期表现出不同的迁移模式，从均匀分布向格陵兰岛西侧过渡，最终向格陵兰岛东侧过渡。为了更深入地研究ARs与质量变化之间的关系，我们利用五年的研究期评估了ARs对格陵兰岛表面质量平衡的贡献。结果表明，AR对中小企业的贡献呈阶段性增加趋势，2000 - 2004年为20.5%，2005 - 2009年为31.5%，2010 - 2014年为46.4%，2015 - 2019年为48.2%。

{"title":"Impact of atmospheric river evolutions on Greenland ice sheet mass changes over the last two decades, 2000–2019","authors":"Jingming Li , Xinyu Qin , Wenhao Li , C.K. Shum , Fei Li , Shengkai Zhang","doi":"10.1016/j.polar.2024.101158","DOIUrl":"10.1016/j.polar.2024.101158","url":null,"abstract":"<div><div>Atmospheric rivers (ARs) serve as mechanisms that transport water vapor to the poles, triggering extreme weather events, altering weather patterns over Greenland, and even impacting mass changes in the Greenland ice sheet. In this study, we detected and extracted ARs spatiotemporal evolution characteristics over Greenland from the past two decades. And subsequently analyzed the Greenland mass changes. Our findings indicate that between 2000 and 2019, the annual occurrences of ARs varied from 13 to 27 times, with durations ranging from 156 to 610 h. Interestingly, the ARs exhibited distinct migration patterns across different periods, transitioning from a uniform distribution towards the west side of Greenland and eventually towards the east side. To delve deeper into the relationship between ARs and mass changes, we assessed the contribution of ARs to Greenland's surface mass balance using a five-year study period. The results show that the contribution of AR to SMB has a tendency to increase in stages, 20.5% from 2000 to 2004, 31.5% from 2005 to 2009, 46.4% from 2010 to 2014, and 48.2% from 2015 to 2019.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101158"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimation of annual and seasonal glaciological-based mass balance of Ladakh range in cold-arid Himalayan region – Case studies of Phuche and Khardung glaciers in 2014–2017 喜马拉雅寒冷干旱地区拉达克山脉年度和季节性冰川学物质平衡估算——以2014-2017年普彻和卡东冰川为例

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101132

Jaydeo K. Dharpure , Ajanta Goswami , Akansha Patel , Sanjay K. Jain , Anil V. Kulkarni

The continuous estimation of glacier surface mass balance (MB) in the cold-arid trans-Himalayan region is crucial for understanding glacier-atmospheric interactions and managing future water resources. Therefore, it is essential to investigate glacier mass variability and its sensitivity to climate drivers. This study uses the direct glaciological surface MB measurements for the Phuche and Khardung glaciers from 2014 to 2017. The mean annual surface MB was observed to be −0.17 for the Phuche glacier and −0.63 m w.e. for the Khardung glacier. The maximum mass loss occurred in 2015/16 for both glaciers. The Phuche glacier experienced positive surface MB in 2014/15 and 2016/17, while the Khardung glacier exhibited negative surface MB throughout the study period. No equilibrium line altitude (ELA) or accumulation area ratio (AAR) was observed either glacier in 2015/16 period. However, the two-year average (2014/15 and 2016/17) ELA and AAR of the Phuche glacier were approximately 5480 m above sea level (asl) and 92%, respectively, while the Khardung glacier they were 5500 m asl and 13%. Results demonstrated that the timing of snowpack melt during the ablation periods significantly influenced glacier mass balance. Overall, the Khardung glacier experienced 3.7 times more mass loss than the Phuche glacier. This higher glacier melt may be attributed to changes in climatic variables and topographical variations.

跨喜马拉雅寒冷干旱地区冰川表面物质平衡（MB）的连续估算对于理解冰川-大气相互作用和管理未来水资源至关重要。因此，研究冰川质量变率及其对气候驱动因子的敏感性是十分必要的。本研究使用2014年至2017年Phuche和Khardung冰川的直接冰川表面MB测量数据。Phuche冰川的年平均地表MB为- 0.17 m， Khardung冰川的年平均地表MB为- 0.63 m。两个冰川的最大质量损失都发生在2015/16年。普彻冰川在2014/15年和2016/17年经历了正地表MB，而哈当冰川在整个研究期间都经历了负地表MB。2015/16年未观测到平衡线高度（ELA）和累积面积比（AAR）。然而，普切冰川的2年平均（2014/15和2016/17）ELA和AAR分别约为海拔5480 m和92%，而哈东冰川的ELA和AAR分别为海拔5500 m和13%。结果表明，消融期积雪融化的时间对冰川物质平衡有显著影响。总的来说，喀当冰川的质量损失是普彻冰川的3.7倍。这种较高的冰川融化可能归因于气候变量和地形变化的变化。

{"title":"Estimation of annual and seasonal glaciological-based mass balance of Ladakh range in cold-arid Himalayan region – Case studies of Phuche and Khardung glaciers in 2014–2017","authors":"Jaydeo K. Dharpure , Ajanta Goswami , Akansha Patel , Sanjay K. Jain , Anil V. Kulkarni","doi":"10.1016/j.polar.2024.101132","DOIUrl":"10.1016/j.polar.2024.101132","url":null,"abstract":"<div><div>The continuous estimation of glacier surface mass balance (MB) in the cold-arid trans-Himalayan region is crucial for understanding glacier-atmospheric interactions and managing future water resources. Therefore, it is essential to investigate glacier mass variability and its sensitivity to climate drivers. This study uses the direct glaciological surface MB measurements for the Phuche and Khardung glaciers from 2014 to 2017. The mean annual surface MB was observed to be −0.17 for the Phuche glacier and −0.63 m w.e. for the Khardung glacier. The maximum mass loss occurred in 2015/16 for both glaciers. The Phuche glacier experienced positive surface MB in 2014/15 and 2016/17, while the Khardung glacier exhibited negative surface MB throughout the study period. No equilibrium line altitude (ELA) or accumulation area ratio (AAR) was observed either glacier in 2015/16 period. However, the two-year average (2014/15 and 2016/17) ELA and AAR of the Phuche glacier were approximately 5480 m above sea level (asl) and 92%, respectively, while the Khardung glacier they were 5500 m asl and 13%. Results demonstrated that the timing of snowpack melt during the ablation periods significantly influenced glacier mass balance. Overall, the Khardung glacier experienced 3.7 times more mass loss than the Phuche glacier. This higher glacier melt may be attributed to changes in climatic variables and topographical variations.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101132"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0