Polar Science最新文献_第6页

Shear Wave Velocity Structure beneath Maitri station in Dronning Maud Land, East Antarctica from Joint Inversions of Rayleigh Wave Ellipticity, Multimode Surface Waves and Diffused Wave Horizontal-to-Vertical Spectral Ratios 基于瑞利波椭圆度、多模面波和扩散波纵横谱比联合反演的东南极洲drning Maud地Maitri站横波速度结构

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-06-01 DOI: 10.1016/j.polar.2025.101208

K. Sivaram , M. Shekar , Satish Saha

Dronning Maud Land (DML) in East Antarctica, a stable cratonic block, is explored to understand the evolution of the Gondwana supercontinent. This study investigates the capabilities of the Rayleigh Wave Ellipticity (RWE) and the horizontal-to-vertical spectral ratio (HVSR), assuming equipartitioned phases or diffused field assumption (DFA) of ambient noise field (ANF), to assess shallow crustal shear velocity. Using data from India's permanent broadband seismic station at Maitri (MAI) in DML, we analyse the crustal and shallow shear velocity in the frequency range 0.02 Hz (50 s period) to 10 Hz (0.1 s period) from 2013 to 2017, excluding disturbance periods. The RWE is extracted with two different methods, and the geometric mean of RWE and HVSR is compared. Both RWE and HVSR curves show a stable shape with a low-frequency peak around ∼0.03 Hz, indicating a deep velocity contrast. A peak near ∼6 Hz is observed but with wide variations and smaller peak amplitudes, possibly due to ice thickness or permafrost variations. Using a reference shear velocity model from a previous receiver function (RF) study at MAI, we apply non-linear inversions on RWE and HVSR (DFA) curves for crustal velocity profiles up to ∼50 km. Joint inversions with multimodal surface-wave dispersion curves minimize inversion non-uniqueness, yielding a good match with RF model. The derived shear velocity models show a distinct velocity contrast at 30–35 km depth (possibly the Moho) and a shallow, low-velocity sedimentary layer at 150–800 m depth, with a possible high-velocity, densified layer at ∼3 km depth.

为了了解冈瓦纳超大陆的演化过程，研究了东南极洲一个稳定的克拉通块体——Dronning Maud Land。本文研究了Rayleigh波椭圆率（RWE）和水平-垂直谱比（HVSR）在假设环境噪声场（ANF）的等分相位或扩散场假设（DFA）的情况下评估浅层地壳剪切速度的能力。利用印度位于DML的Maitri （MAI）永久宽带地震台站的数据，我们分析了2013年至2017年在0.02 Hz （50 s周期）至10 Hz （0.1 s周期）频率范围内的地壳和浅层剪切速度，不包括扰动期。采用两种不同的方法提取RWE，并比较了RWE和HVSR的几何平均值。RWE和HVSR曲线都显示出稳定的形状，低频峰值在~ 0.03 Hz左右，表明深度速度对比。在~ 6 Hz附近观测到一个峰值，但变化很大，峰值幅度较小，可能是由于冰厚或永久冻土的变化。利用MAI先前接收函数（RF）研究的参考剪切速度模型，我们对地壳速度剖面的RWE和HVSR （DFA）曲线进行非线性反演，反演范围为~ 50 km。利用多模态面波频散曲线联合反演可以最大限度地减少反演的非唯一性，与射频模型的拟合效果较好。导出的剪切速度模型显示，在30-35 km深度（可能是莫霍）有明显的速度对比，在150-800 m深度有一个浅的低速沉积层，在~ 3 km深度可能有一个高速致密层。

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引用次数: 0

Fragmented Arctic science: Permafrost as a salient feature in the divergence between geopolitical and chronopolitical perspectives 支离破碎的北极科学：永久冻土是地缘政治和时间政治观点分歧的一个显著特征

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-06-01 DOI: 10.1016/j.polar.2025.101207

Florian Vidal , Louna Saas

Russia’s war in Ukraine has drastically affected the Arctic governance, freezing institutional mechanisms established in the post-Cold War period. Among the lasting consequences, scientific cooperation between Western and Russian research communities has been impaired involving international projects on critical environmental issues in the polar region. Although joint research activities have been curtailed since February 2022, efforts have been made to revive Arctic scientific dialogue to address the pressing concerns related to rapid climate change in the polar region. Monitoring permafrost conditions is a key feature in anticipating the future trajectory of the planet. However, about 65% of Russia’s territory is covered by permafrost, which represents a serious blind spot for the Western scientific community without data access. Given the current geopolitical breakdown, this situation could jeopardize climate modeling and ultimately pose a threat to international security. At the same time, Russia is pursuing and developing Arctic scientific cooperation with non-Western partners, including China and India. These countries are now becoming competitors with the Western research community, thereby creating alternative channels for the flow of scientific knowledge. Using the example of permafrost research, this article examines the long-term implications of the decoupling of Russia and the West in the domain of polar science.

俄罗斯在乌克兰的战争极大地影响了北极的治理，冻结了冷战后时期建立的体制机制。在持久的后果中，西方和俄罗斯研究界之间的科学合作在涉及极地地区关键环境问题的国际项目方面受到损害。尽管自2022年2月以来，联合研究活动受到了限制，但各方仍在努力恢复北极科学对话，以解决与极地地区快速气候变化有关的紧迫问题。监测永久冻土条件是预测地球未来轨迹的一个关键特征。然而，大约65%的俄罗斯领土被永久冻土覆盖，这对西方科学界来说是一个严重的盲区，无法获得数据。鉴于当前地缘政治的崩溃，这种情况可能危及气候模型，并最终对国际安全构成威胁。与此同时，俄罗斯正在寻求和发展与包括中国和印度在内的非西方伙伴的北极科学合作。这些国家现在正成为西方研究界的竞争对手，从而为科学知识的流动创造了另一种渠道。本文以永久冻土研究为例，探讨了俄罗斯与西方在极地科学领域脱钩的长期影响。

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引用次数: 0

Sustainable development in the Arctic for Indigenous peoples 土著人民在北极的可持续发展

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-06-01 DOI: 10.1016/j.polar.2025.101217

Yuko Osakada

Sustainable development in the Arctic is a goal, process and outcome desired by four million Arctic residents, including diverse Indigenous communities. The cross-disciplinary international seminar “Sustainable Development in the Arctic for Indigenous Peoples” was organised by the Arctic Challenge for Sustainability II (ArCS II) Research Programs on International Law, Human Society, and Coastal Environments, starting on 9 September 2023 for two consecutive days. The purpose of the seminar was to identify what efforts are being made for sustainable development in the Arctic and to understand its significance and challenges for Indigenous peoples. The special feature “Sustainable Development in the Arctic for Indigenous Peoples” consists of six papers presented at this international seminar.

北极的可持续发展是400万北极居民的共同目标、共同进程和共同成果。由北极可持续发展挑战II （ArCS II）国际法、人类社会和沿海环境研究项目组织的“北极土著人民的可持续发展”跨学科国际研讨会于2023年9月9日开始，为期两天。讨论会的目的是确定正在为北极的可持续发展作出哪些努力，并了解其对土著人民的意义和挑战。专题“北极土著人民的可持续发展”由本次国际研讨会上发表的六篇论文组成。

引用次数: 0

Development of long-term monitoring of Antarctic moss banks to recent climate changes 南极苔藓库对近期气候变化的长期监测进展

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-06-01 DOI: 10.1016/j.polar.2025.101174

Anton Puhovkin , Taras Kazantsev , Miloš Barták , Yuriy Shepeta , Artem Dzhulai , Natalia Miryuta , Josef Hájek , Ivan Parnikoza

The parameters of four moss banks in Argentine Islands were studied. Using unmanned aerial vehicle, we distinguished green and non-green color classes of moss in order to evaluate interannual changes. Spectral reflectance data were recorded and the normalized difference vegetation index (NDVI) values were calculated for each color class. Interannually, NDVI of green class cover increased, indicating a possible positive impact of integrate environmental factors. Laboratory measurements revealed a significant difference in chlorophyll content and shape of spectral reflectance curves (380–790 nm) for color classes of two dominant species of the moss communities, Polytrichum strictum and Sanionia georgicouncinata. The analysis of spectral indices revealed color-dependent differences in NDVI and other indices; photochemical reflectance index and NDVI were discovered to be the most sensitive to detect color classes. Chlorophyll fluorescence transients (OJIPs) and OJIP-derived parameters decreased in both species from green to non-green class due to the progressive decline in chlorophyll content and its ability to perform Photosystem II related photosynthetic processes. Thus, the green color class is healthy with a high chlorophyll content while the non-green is unhealthy, that can be used as an indicator of changes in the state of moss bank for the long-term monitoring.

对阿根廷群岛4个苔藓群落的参数进行了研究。利用无人机对苔藓的绿色和非绿色进行分类，评价苔藓的年际变化。记录光谱反射率数据，并计算各色类的归一化植被指数（NDVI）值。绿色覆盖NDVI年际呈增加趋势，表明综合环境因子可能对其产生积极影响。室内测量结果显示，两种优势种藓类的叶绿素含量和光谱反射曲线形状（380 ~ 790 nm）在色级上存在显著差异。光谱指数分析显示NDVI和其他指数的颜色依赖性差异；光化学反射指数和NDVI对颜色分类最敏感。叶绿素荧光瞬态（OJIPs）和OJIPs衍生的参数在这两个物种中从绿色到非绿色都有所下降，这是由于叶绿素含量及其进行光系统II相关光合过程的能力逐渐下降。因此，绿色类是健康的，叶绿素含量高，而非绿色类是不健康的，可以作为苔藓库状态变化的指标，进行长期监测。

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引用次数: 0

First record of a halacarid mite Bradyagaue drygalskii (Halacaroidea, Acari) from Lützow-Holm Bay in East Antarctica 东南极洲l<s:1> zow- holm湾halacaria螨Bradyagaue drygalskii （halacaro总科，螨目）的首次记录

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101131

Hiroshi Abé , Ichiro Takeuchi

A halacarid mite, Bradyagaue drygalskii (Lohmann, 1907), in the family Halacaridae, was discovered from the brown alga Desmarestia chordalis Hooker and Harvey, 1845, at a depth of 12 m in Lützow-Holm Bay on the East Antarctic coast during the 35th Japanese Antarctic Research Expedition in 1994. This is the first record of B. drygalskii from the region of Queen Maud Land to Enderby Land in East Antarctica. This finding supports the contention that B. drygalskii will be distributed widely in Antarctica. The results of morphological comparison and distributional records for Bradyagaue species described so far suggested that B. aspidionis Newell, 1984, and B. drygalskii are likely to be conspecific. However, further detailed comparisons are necessary to clarify the taxonomic relationship between these two species based on a greater number of individuals.

1994年第35次日本南极科考考察队在南极东海岸l佐霍尔姆湾12米深处从褐藻Desmarestia chordalis中发现了一种Halacaridae螨，Bradyagaue drygalskii (Lohmann, 1907)，属于Halacaridae科。这是东南极洲莫德女王地至恩德比地地区首次记录到drygalskii。这一发现支持了B. drygalskii将在南极洲广泛分布的论点。经形态学比较和分布记录的结果表明，B. aspidionis Newell， 1984和B. drygalskii可能是同种的。然而，为了在更多的个体数量的基础上阐明这两个物种之间的分类关系，还需要进一步的详细比较。

引用次数: 0

Characterization of marine litter in the vicinity of the Machu Picchu Scientific Base, King George Island, Antarctica 南极洲乔治王岛马丘比丘科学基地附近海洋垃圾的特征

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2025.101170

Gabriel Enrique De-la-Torre , Williams Ramos , Victor Pretell , Luis Santillán

In the present study, marine litter in the vicinity of the Machu Picchu Scientific Base, Antarctica, was quantified and characterized. A total of 33 items were counted, primarily composed of plastic debris and foams, followed by metallic structures. A high abundance of marine litter was associated with the proximity to the scientific base. Common plastic polymers were identified by Fourier-transformed infrared spectroscopy, including polypropylene, polyethylene, polyurethane, acrylates, and polystyrene. The abundance of synthetic polymer materials could potentially release toxic chemicals and microplastics into the environment. We suspect that permanent and seasonal Antarctic bases' maintenance and operation release large amounts of structural waste to their surroundings and lack proper solid waste management. For this reason, enforcing solid waste management systems and internal regulations is necessary to follow the guidelines of the Protocol on Environmental Protection to the Antarctic Treaty.

本研究对南极洲马丘比丘科学基地附近的海洋垃圾进行了定量分析和表征。总共统计了33件物品，主要由塑料碎片和泡沫组成，其次是金属结构。大量的海洋垃圾与靠近科学基地有关。用傅里叶变换红外光谱法鉴定了常见的塑料聚合物，包括聚丙烯、聚乙烯、聚氨酯、丙烯酸酯和聚苯乙烯。大量的合成高分子材料可能会向环境中释放有毒化学物质和微塑料。我们怀疑，南极永久性和季节性基地的维护和运营向周边地区排放了大量的结构垃圾，并且缺乏适当的固体废物管理。因此，必须执行固体废物管理制度和内部条例，以遵循《南极条约关于环境保护的议定书》的准则。

引用次数: 0

Predictability and applicability evaluation of winter temperatures in China based on Eurasian Arctic sea ice concentrations in autumn 基于欧亚北极海冰秋季浓度的中国冬季气温可预测性及适用性评价

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101133

Y. Ma , L. Zhao , J.-S. Wang , Q. Wu , X. Li , Q. Li , W. Cheng , T. Yu , L. Sun

The current trends of a warming Arctic and a reduction in Arctic sea ice lead to remote effects on climate anomalies in mid-latitude regions. We investigate the predictability of winter temperatures in China using an empirical regression model to forecast those temperatures based on the Eurasian Arctic sea ice concentration (SIC) in autumn and explore the applicability of this prediction method. Result shows the September Eurasian SIC achieves a highly skilled seasonal prediction of winter temperature anomalies in China. A cross-validated hindcast for the leading principal component of winter temperatures in China using the September SIC within the region (40–150° E, 65–85° N) yields a correlation skill of 0.47 from 1979 to 2018. This suggests that 22% of winter temperature variance in China can be predicted by the Eurasian SIC two months in advance. Winter temperature hindcast/forecast results indicate that September SIC demonstrates a positive temporal anomaly correlation coefficient at most stations in China, with a spatial average reaching 0.32/0.29. However, its forecasting ability for the magnitude of temperature anomalies is relatively weak. Lower tropical Pacific Ocean temperatures, a weak polar vortex, and a strong Ural blocking (UB) in autumn could improve Eurasian SIC's predictive performance.

目前北极变暖和北极海冰减少的趋势导致对中纬度地区气候异常的远程影响。基于欧亚北极海冰浓度（SIC），利用经验回归模型对中国冬季气温进行了预测，并探讨了该预测方法的适用性。结果表明，9月份欧亚大陆SIC对中国冬季气温异常具有较好的季节预测能力。利用区域（40-150°E, 65-85°N） 9月SIC对中国冬季气温的主成分进行交叉验证的后验，得出1979 - 2018年的相关技能为0.47。这表明，中国冬季气温变化的22%可以通过欧亚SIC提前两个月进行预测。冬季气温预报结果表明，9月份中国大部分站点的SIC时间异常相关系数均为正相关，空间平均值为0.32/0.29。但其对气温异常幅度的预测能力相对较弱。较低的热带太平洋温度、较弱的极地涡旋和秋季较强的乌拉尔阻塞（UB）可以提高欧亚大陆SIC的预测性能。

{"title":"Predictability and applicability evaluation of winter temperatures in China based on Eurasian Arctic sea ice concentrations in autumn","authors":"Y. Ma , L. Zhao , J.-S. Wang , Q. Wu , X. Li , Q. Li , W. Cheng , T. Yu , L. Sun","doi":"10.1016/j.polar.2024.101133","DOIUrl":"10.1016/j.polar.2024.101133","url":null,"abstract":"<div><div>The current trends of a warming Arctic and a reduction in Arctic sea ice lead to remote effects on climate anomalies in mid-latitude regions. We investigate the predictability of winter temperatures in China using an empirical regression model to forecast those temperatures based on the Eurasian Arctic sea ice concentration (SIC) in autumn and explore the applicability of this prediction method. Result shows the September Eurasian SIC achieves a highly skilled seasonal prediction of winter temperature anomalies in China. A cross-validated hindcast for the leading principal component of winter temperatures in China using the September SIC within the region (40–150° E, 65–85° N) yields a correlation skill of 0.47 from 1979 to 2018. This suggests that 22% of winter temperature variance in China can be predicted by the Eurasian SIC two months in advance. Winter temperature hindcast/forecast results indicate that September SIC demonstrates a positive temporal anomaly correlation coefficient at most stations in China, with a spatial average reaching 0.32/0.29. However, its forecasting ability for the magnitude of temperature anomalies is relatively weak. Lower tropical Pacific Ocean temperatures, a weak polar vortex, and a strong Ural blocking (UB) in autumn could improve Eurasian SIC's predictive performance.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"43 ","pages":"Article 101133"},"PeriodicalIF":1.5,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143579390","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

Molecular signatures of environmental adaptation mechanisms of Rhizocarpon geographicum in Horseshoe Island (west of the Antarctic Peninsula) and Türkiye 马蹄铁岛（南极半岛西部）和<s:1> rkiye地区地理根茎霉环境适应机制的分子特征

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101134

Ekrem Bölükbaşı , Mehmet Gökhan Halıcı

The adaptation of lichen species to different habitats and extreme conditions is due to rapid changes in expressions of the genes in their genetic backgrounds. In this study, lichen samples were collected from two different regions: from Horseshoe Island, located to the west of the Antarctic Peninsula and from the west coast of Türkiye. The nrITS gene regions of the samples were studied and the phylogenetic positions of the samples were confirmed as Rhizocarpon geographicum (L.) DC. After DNA barcoding of R. geographicum, expression differences of three below-specified stress genes were revealed. Comparative determinations of the changes in the expressions of the multiprotein binding factor-1 (MBF-1), polyketide synthase (PKS), and photosystem II D1 protein (psbA) genes due to temperature or other environmental stress change stress were performed by a real-time PCR. Specifically, under cold stress conditions such as those found on Horseshoe Island, the MBF-1 gene was highly expressed, while PKS and psbA gene expression levels were lower compared to the west coast of Türkiye. The results of this study, which is the first in its field, highlight the adaptation of Rhizocarpon geographicum specimens to those habitats and regional climate. Specimen collected from different geographical regions exhibited gene expression differences.

地衣物种对不同生境和极端条件的适应是由于其遗传背景中基因表达的快速变化。在这项研究中，地衣样本是从两个不同的地区收集的：位于南极半岛西部的马蹄岛和t rkiye西海岸。对样品的nrITS基因区域进行了研究，确定了样品的系统发育位置为Rhizocarpon geographicum （L.）。直流。对地瓜进行DNA条形码分析，揭示了3个特定胁迫基因的表达差异。采用实时荧光定量PCR法比较测定温度或其他环境胁迫变化对多蛋白结合因子-1 （MBF-1）、多酮合成酶（PKS）和光系统II D1蛋白（psbA）基因表达的影响。具体而言，在马蹄铁岛等寒冷胁迫条件下，MBF-1基因表达量高，而PKS和psbA基因表达水平低于 rkiye西海岸。本研究在该领域尚属首次，突出了根卡蓬地理标本对这些生境和区域气候的适应性。来自不同地理区域的标本表现出基因表达的差异。

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引用次数: 0

Projected changes in near-surface wind speed in the Arctic by a regional climate model 区域气候模式对北极近地表风速变化的预估

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2024.101162

Mirseid Akperov , Wenxin Zhang , Torben Koenigk , Alexey Eliseev , Vladimir A. Semenov , Igor I. Mokhov

This study investigates seasonal changes in near-surface wind speeds in the Arctic using the regional climate model (RCM) simulations with RCA4 driven by four global climate models (GCMs) CMIP5 under Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios. In addition, the RCM RCA-GUESS (RCA4 with interactive vegetation dynamics) is used to investigate the role of biogeophysical feedbacks in modulating near-surface wind speeds under different RCP scenarios. Our results show that the reduction in ocean surface roughness induced by sea-ice reduction leads to a projected increase in near-surface wind speeds over the Arctic Ocean, with the most pronounced effects occurring in autumn and winter. Overall, the projected changes in near-surface wind speeds from the RCM are consistent with the changes from the forcing GCMs though the RCM simulations show larger amplitude changes compared to the GCMs. The expansion of vegetation on land increases surface roughness and alters atmospheric circulation by modifying static stability and the land-sea temperature contrast, leading to changes in near-surface wind speeds. Specifically, wind speeds decrease over continental regions but increase over parts of the Arctic Ocean. This study emphasizes that interactive vegetation dynamics significantly influence changes in land surface properties and near-surface wind speeds. These processes should be incorporated into Earth system models to enhance the accuracy of future climate projections.

在代表性浓度路径（RCP） 4.5和8.5情景下，采用区域气候模式（RCM）模拟北极近地面风速的季节变化。此外，利用RCM RCA-GUESS （RCA4 with interactive vegetation dynamics）研究了不同RCP情景下生物地球物理反馈对近地面风速的调节作用。我们的研究结果表明，海冰减少引起的海洋表面粗糙度的降低导致北冰洋近地面风速的预估增加，其中秋季和冬季的影响最为明显。总的来说，RCM对近地面风速的预估变化与强迫gcm的变化是一致的，尽管RCM模拟的变化幅度比gcm大。陆地植被的扩张增加了地表粗糙度，并通过改变静稳定性和海陆温对比改变大气环流，从而导致近地面风速的变化。具体来说，大陆地区的风速降低，但北冰洋部分地区的风速增加。本研究强调植被的相互作用动态对地表特性和近地表风速的变化有显著影响。这些过程应纳入地球系统模式，以提高未来气候预测的准确性。

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引用次数: 0

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2025.101165

Vladimir Maderich , Roman Bezhenar , Igor Brovchenko , Fabio Boeira Dias , Cecilia Äijälä , Petteri Uotila

We compared circulations under the Filchner-Ronne Ice Shelf (FRIS) and the Ross Ice Shelf (RIS) using output from the Whole Antarctica Ocean Model driven by repeated year atmospheric forcing and processed by the particle-tracking Parcels model. Three Lagrangian characteristics were calculated: the visitation frequency, the mean age, and the representative particle trajectory. In both FRIS and RIS, the High Salinity Shelf Water (HSSW) entered through depressions off the western coast of ice shelves. We found that HSSW transformed into the Ice Shelf Water that departed both ice shelves at central ice front locations (approximately 58-57°W in Ronne Ice Shelf and 175°W in RIS). The outflow through the Ronne Ice Front we identified has not attracted attention until now, although it has been observed. Almost half of the particles departed FRIS through the Ronne Ice Front, whereas about 20% stayed under FRIS. The rest of the particles flow out through the Filchner Trough. In contrast, only 2% of the particles stayed under RIS. The mean age of water leaving FRIS through the Ronne Ice Front and the water leaving RIS was 7–8 years, whereas the water leaving FRIS through the Filchner Trough was about 10 years.

我们利用由重复年度大气强迫驱动并经过粒子跟踪包裹模式处理的整个南极洲海洋模式的输出，比较了Filchner-Ronne冰架（FRIS）和Ross冰架（RIS）下的环流。计算了三个拉格朗日特征：访问频率、平均年龄和代表性粒子轨迹。在FRIS和RIS中，高盐度陆架水（HSSW）都是通过冰架西海岸的洼地进入的。我们发现，在中心冰锋位置（Ronne冰架约为58-57°W， RIS冰架约为175°W）， HSSW转化为冰架水，离开两个冰架。我们发现的通过罗纳冰锋的外流直到现在才引起人们的注意，尽管它已经被观察到。几乎一半的颗粒通过Ronne冰锋离开FRIS，而大约20%留在FRIS之下。其余的颗粒通过费尔奇纳槽流出。相比之下，只有2%的颗粒留在RIS下。通过Ronne冰锋和离开RIS的水平均年龄为7 ~ 8年，而通过Filchner槽离开FRIS的水平均年龄约为10年。

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引用次数: 0