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Granulite facies metamorphism of the metasediments from Tallaksenvarden and Starheimtind nunataks, central Dronning Maud Land (cDML), East Antarctica and their correlation with the eastern granulites of the East African Orogen (EAO) 东南极洲中部Dronning Maud Land (cDML) Tallaksenvarden和Starheimtind nunataks沉积的麻粒岩相变质作用及其与东非造山带东部麻粒岩的对比

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2025-03-01 DOI: 10.1016/j.polar.2025.101166

Raghuram , Mohd Yunus Shah , Monika Mishra , Anubha Bhandari , Raymond Duraiswami

There are eight nunataks in cDML exposed through the vast expanse of the ice sheet between Schirmacher Oasis and the Gruber–Wohlthat Mountains. Tallaksenvarden and Starheimtind are two important nunataks that mark the eastern and western limits of their exposures. There is paucity of the metamorphic data from these nunataks which otherwise lie between the well-studied Schirmacher Oasis and Humboldt Range. These nunataks comprise a sequence of granulite facies metasedimentary rocks interlayered with pyroxene granulite. The granulite facies assemblage in the pelitic granulite is garnet + sillimanite ± kyanite + biotite + quartz + perthite ± plagioclase ± rutile ± ilmenite. P-T-t path estimations reveal ultrahigh temperature (UHT) metamorphism (M₂, ca.630-570 Ma) with a clockwise path (>900 °C at ≥8 kbar) during the Cryogenian-Cambrian period well above the wet granite solidus for incongruent melting with significant increase in melt volume during decompression. Yttrium in garnet thermometry combined with textural evidence (symplectitic quartz, biotite and plagioclase embayment in porphyroblasts) suggest initiation of porphyroblasts growth in the pelitic granulite at c. 550 °C with continued growth during increase in temperature (∼645 °C) followed by resorption and growth coinciding with increased melt generation. These nunataks and Schirmacher Oasis expose the same lithopackage with identical metamorphic and structural evolution possibly extending southward till the inland mountains of the cDML. This study also identifies that these nunataks indeed represent a portion of the EAO with a possible transpressive deformation regime.

在Schirmacher绿洲和Gruber-Wohlthat山脉之间的广阔冰原上，cDML有8个冰原。Tallaksenvarden和Starheimtind是两个重要的冰峰，标志着它们暴露的东西界限。这些火山喷发的变质资料很少，否则它们就位于研究得很充分的希尔马赫绿洲和洪堡山脉之间。这些麻粒岩由麻粒岩相变质沉积岩序列与辉石麻粒岩层间组成。泥质麻粒岩的麻粒岩相组合为石榴石+硅线石±蓝晶石+黑云母+石英+花青石±斜长石±金红石±钛铁矿。P-T-t路径估计显示，在低温-寒武纪期间，超高温（UHT）变质作用（M2，约630-570 Ma）具有顺时针路径（>900°C,≥8 kbar），远高于湿花岗岩固相，导致不一致熔融，减压期间熔体体积显著增加。石榴石测温中的钇结合结构证据（斑疹母岩中的硅晶石英、黑云母和斜长石）表明，斑疹母岩在550℃时开始在泥质麻粒岩中生长，在温度升高（~ 645℃）期间继续生长，随后吸收和生长与熔体生成的增加相一致。这些nunataks和Schirmacher绿洲暴露出相同的岩石包，具有相同的变质作用和构造演化，可能向南延伸至cDML的内陆山脉。本研究还发现，这些风侵活动确实代表了EAO的一部分，可能具有压迫变形机制。

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引用次数: 0

Assessment of various microwave brightness temperature products and methods for surface melt detection over Greenland ice sheet 格陵兰冰盖表面融化探测的各种微波亮度温度产品和方法评估

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101097

Pooja Mishra , Naveen Tripathi , S.R. Oza , S.K. Singh , N.Y. Bhatt , P.M. Solanki

Microwave brightness temperature have widely been used for the detection of the ice sheet's surface melt conditions and understanding their spatio-temporal variability. In this study, we investigated the sensitivity of microwave brightness temperature products from three different sensors, namely, Advanced Microwave Scanning Radiometer-2 (AMSR2), Special Sensor Microwave Imager/Sounder (SSMIS) and Indian scatterometer satellite (SCATSAT-1) for surface melt detection over the Greenland ice sheet (GrIS). In-situ air temperature measurements from GC-Net AWSs were used for sensitivity and inter-comparison analysis. Our findings show that brightness temperature (T_b) from SSMIS better correlates (P_coef = 0.81 for 19 GHz) with air temperature measurements in comparison to AMSR2 (P_coef = 0.7 for 18 GHz) and SCATSAT-1 (P_coef = 0.67). However, interestingly, AMSR2 and SCATSAT-1 uniquely discriminated the surface conditions during pre- and post-melt period, due to their heterogeneity in T_b values during the two period. Error analysis with respect to AWS melt days shows that SSMIS 19 GHz T_b (T_b/SSMIS/19H) products with TED method giving the most promising observations. A wide variability in T_b values is observed during the melt season across the various AWS sites depending upon the elevation, location and frequency. During our study period, using T_b/SSMIS/19H for TED method, we observed the highest melt extent area for the extreme melt event in year 2019 (∼1.12 million km²), followed by another melt event year 2021 when it went as high as ∼1.02 million km².

微波亮度温度已被广泛用于探测冰盖表面融化状况并了解其时空变化。本文研究了先进微波扫描辐射计-2 （AMSR2）、特殊传感器微波成像仪/探测仪（SSMIS）和印度散射计卫星（SCATSAT-1）三种不同传感器的微波亮度温度产品在格陵兰冰盖（GrIS）表面融化探测中的灵敏度。使用GC-Net AWSs的现场空气温度测量值进行灵敏度和相互比较分析。我们的研究结果表明，与AMSR2 （18 GHz Pcoef = 0.7）和SCATSAT-1 （Pcoef = 0.67）相比，SSMIS的亮度温度（Tb）与空气温度测量的相关性（19 GHz Pcoef = 0.81）更好。然而，有趣的是，由于AMSR2和SCATSAT-1在两个时期的Tb值的异质性，它们独特地区分了融化前和融化后的表面状况。对AWS熔化日的误差分析表明，采用TED方法的SSMIS 19 GHz Tb （Tb/SSMIS/19H）产品给出了最有希望的观测结果。在融化季节，根据海拔、位置和频率的不同，在不同的AWS站点上观察到Tb值的广泛变化。在我们的研究期间，使用Tb/SSMIS/19H for TED方法，我们观察到2019年极端融化事件的最高融化范围面积（~ 112万平方公里），其次是2021年的另一个融化事件，当时它高达~ 102万平方公里。

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引用次数: 0

Rapid deceleration in the ice-flow velocity of the Shirase Glacier ice tongue and its influence on the velocity field: Observations from Sentinel-1 C-SAR 白濑冰川冰舌冰流速度的快速减速及其对速度场的影响：来自哨兵-1 C-SAR 的观测数据

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101109

S. Ohkawa , K. Doi , K. Nakamura , Y. Aoyama , H. Nagai

Temporal and spatial variations in the ice-flow speed of Shirase Glacier ice tongue in East Antarctica between July 2018 and December 2021 were investigated using Sentinel-1 C-band Synthetic Aperture Radar (C-SAR) imagery. We identified pronounced slowdown events in the eastern part of the outer ice tongue, 30–40 km from the grounding line in 2020 and 55 km in 2021. Comparison of ice thickness and bathymetry in areas where the deceleration events occurred suggests that the events were caused by icebergs grounding or landing on the seafloor. The absence of slowdown propagation towards the grounding line demonstrates the ice tongue offers very limited buttressing. This study contributes to a better understanding of the factors influencing glacier dynamics, particularly in the context of grounding events and their localized impacts.

利用哨兵-1 C 波段合成孔径雷达（C-SAR）图像研究了 2018 年 7 月至 2021 年 12 月期间南极洲东部白濑冰川冰舌冰流速度的时空变化。我们在外层冰舌东部发现了明显的减速事件，2020 年在距接地线 30-40 公里处，2021 年在距接地线 55 公里处。对发生减速事件区域的冰层厚度和水深进行比较后发现，减速事件是由冰山接地或着陆到海底引起的。向接地线方向没有减速传播表明冰舌提供的支撑非常有限。这项研究有助于更好地了解影响冰川动力学的因素，特别是在接地事件及其局部影响方面。

引用次数: 0

Mercury levels in tissues (cartilage, skin, and muscle) of the Greenland shark (Somniosus microcephalus): Potential contamination sources and implications for health and conservation 格陵兰鲨（Somniosus microcephalus）组织（软骨、皮肤和肌肉）中的汞含量：潜在污染源及其对健康和保护的影响

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101079

Sebastian Biton-Porsmoguer , Françoise Marco-Miralles , Marc Bouchoucha

The jaws of the Greenland shark have high levels of mercury. Hg of cartilage in comparison with skin and muscle from the same specimen makes it possible to apprehend the distribution of the pollutant in the body. The level of the pollutant between jaw, skin and fresh meat (muscle) shows a strong correlation. The muscle is the most contaminated element in comparison with the skin and cartilage. The species presents the highest levels among different groups of sharks and the results are in accordance with previous studies. Marine ecosystems in the Arctic are globally contaminated by mercury (atmosphere, water, sediments, food web). The methylmercury reduces blood calcium levels, directly affecting the metabolism of cartilage cells. Even if cases of malformations could not be observed in the Greenland shark, numerous cases for other shark species have been documented in connection with heavy metals (e.g., Hg), and in particular for aplacental viviparous with potential morphological anomalies on embryos. The situation of the Greenland shark is worrying due to the conservation status, the fishing catches, the tardive sexual maturity and reproduction, the climate change and the level of mercury on its organism. The results incite to recommend ecological, environmental and fisheries management measures.

格陵兰鲨鱼的下颌中汞含量很高。将软骨的汞含量与同一标本的皮肤和肌肉进行比较，可以了解污染物在体内的分布情况。下颚、皮肤和鲜肉（肌肉）之间的污染物水平表现出很强的相关性。与皮肤和软骨相比，肌肉是受污染最严重的部分。该物种在不同种类的鲨鱼中含量最高，结果与先前的研究一致。北极的海洋生态系统在全球范围内受到汞的污染（大气、水、沉积物、食物网）。甲基汞降低血钙水平，直接影响软骨细胞的代谢。即使在格陵兰鲨中没有观察到畸形的病例，也有许多其他鲨鱼物种的病例与重金属（如汞）有关，特别是胎盘胎生的胚胎可能出现形态异常。由于格陵兰鲨的保护状况、捕捞量、性成熟和繁殖迟缓、气候变化以及其体内的汞含量，格陵兰鲨的状况令人担忧。研究结果有助于提出生态、环境和渔业管理措施。

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引用次数: 0

Unveiling risk factors influencing the selection of the Northern Sea Route: A conjoint analysis approach for Japanese shippers 揭示影响北海航线选择的风险因素：日本托运人的联合分析方法

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101129

Shinichi Yamaguchi , Hidetaka Oshima , Shinnosuke Tanabe , Hajime Yamaguchi

This paper explores how Japanese corporations assess risks associated with using the Northern Sea Route (NSR) as a new maritime transport route in Asia and identifies measures to promote its usage. We address two key questions: (1) What risks influence shippers' route choices in maritime transport? (2) Does risk evaluation vary by cargo type and company size? Using choice-based conjoint analysis and a conditional logit model with online survey data, we identified five main risk factors influencing shippers: route unavailability rate, delay probability, piracy probability, transport costs, and war conditions, ranked in importance from highest to lowest as war conditions, delay probability, transport costs, route unavailability rate, and piracy probability. Additionally, the risk factors significantly influencing route selection were found to be robust, showing minimal variation across company size, type of trade (import/export), and the nature of the goods transported. Our findings suggest several policy implications. Diplomatic efforts are crucial for safe vessel navigation on the NSR. Government initiatives should focus on reducing transport delays through technology investments and implementing strategies to decrease NSR delay rates without increasing shippers' costs. Additionally, emphasizing the lower piracy risks on the NSR compared to Suez Canal Route could boost its attractiveness.

本文探讨了日本企业如何评估使用北方海路（NSR）作为亚洲新海运路线的相关风险，并确定了促进其使用的措施。我们解决了两个关键问题：(1)在海上运输中，哪些风险影响托运人的航线选择？(2)风险评估是否因货物类型和公司规模而异？利用基于选择的联合分析和基于在线调查数据的条件logit模型，我们确定了影响托运人的五个主要风险因素：路线不可用率、延误概率、海盗概率、运输成本和战争条件，从高到低依次为战争条件、延误概率、运输成本、路线不可用率和海盗概率。此外，发现显著影响路线选择的风险因素是稳健的，在公司规模、贸易类型（进口/出口）和运输货物性质之间的差异最小。我们的研究结果提出了几个政策启示。外交努力对船只在北极航道上的安全航行至关重要。政府的举措应侧重于通过技术投资和实施战略，在不增加托运人成本的情况下减少运输延误。此外，与苏伊士运河航线相比，强调北方航道的海盗风险较低可能会提高其吸引力。

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引用次数: 0

Annual velocities of the ablation zone of Panchi Nala Glacier, western Himalaya: Trends and controlling factors 喜马拉雅山西部 Panchi Nala 冰川消融区的年速度：趋势和控制因素

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101068

Purushottam Kumar Garg , Mohit Prajapati , Aparna Shukla , Supratim Guha , Iram Ali

Information on the glacier velocity is imperative to understand the glacier ice volume, supraglacial feature evolution and glacier-climate interaction. The present study investigates annual velocities of the ablation zone (∼4500–4800 m asl) of Panchi Nala Glacier, western Himalaya through feature tracking. For this, multi-temporal Landsat (TM and OLI) and Sentinel −2 MSI images, acquired between 2000 and 2021, were correlated using the Co-registration of Optically Sensed Images and Correlation (COSI-Corr) tool. Results reveal a mean velocity of the ablation zone to be 10.6 ± 5.6 m/y during 2000–2021, with the highest (13.8 ± 4.6 m/y) and lowest velocity (8.9 ± 2.8 m/y) observed in 2005 and 2015, respectively. There is no significant trend in the velocity, rather it is highly heterogeneous on the inter-annual scale. Further, the influence of several factors such as slope, debris cover, altitude, annual average temperature and precipitation on the glacier velocity was investigated. Results indicate that the inter-annual heterogeneity in velocity is inversely correlated with the variation of summer precipitation implying that an increase in summer precipitation decreases the glacier velocity. The spatio-temporal velocity variations are also linked with the presence of supraglacial ponds, ice cliffs and heterogeneous debris distribution over the glacier. Findings indicate that, though annual glacier velocities have not changed significantly, their magnitudes are consistently low which coupled with consistent debris increase (19.74%) and gentle slope (8.2° over ablation zone) can promote rapid growth of supraglacial ponds and ice cliffs.

关于冰川速度的信息对于了解冰川冰量、冰上特征演化和冰川-气候相互作用至关重要。本研究通过特征跟踪研究了喜马拉雅西部Panchi Nala冰川消融带（~ 4500-4800 m asl）的年速度。为此，使用光学感测图像和相关性（cos - corr）工具对2000年至2021年期间获得的多时段Landsat （TM和OLI）和Sentinel - 2 MSI图像进行了关联。结果表明，2000-2021年期间，消融区的平均速度为10.6±5.6 m/y，其中2005年和2015年的速度最高（13.8±4.6 m/y），最低（8.9±2.8 m/y）。在年际尺度上，速度变化趋势不明显，具有高度的不均匀性。此外，还研究了坡度、碎屑盖度、海拔、年平均气温和降水量等因素对冰川流速的影响。结果表明，冰川速度的年际异质性与夏季降水的变化呈负相关，表明夏季降水的增加会降低冰川速度。时空速度变化还与冰川上的冰池、冰崖和非均质碎屑分布有关。结果表明，虽然冰川速度的年际变化不明显，但其幅度一直较低，加之碎屑持续增加（19.74%）和平缓坡度（消融带上8.2°），可以促进冰上塘和冰崖的快速生长。

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引用次数: 0

ALBATROSS: Advancing Southern Ocean tide modelling with high resolution and enhanced bathymetry 信天翁：推进南大洋潮汐模型的高分辨率和增强的水深测量

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101124

Eva Le Merle , Carole Belot , Ergane Fouchet , Mathilde Cancet , Ole Baltazar Andersen , Florent Lyard , Geir Moholdt , Michel Tsamados , Mahmoud El Hajj , Josephine Maton , Jérôme Benveniste , Marco Restano

The knowledge of bathymetry and ocean tides plays a pivotal role at the crossroads of various scientific fields, especially in the Polar regions. Its significance extends to ocean circulation modeling and understanding the coupled dynamical response of the ocean, sea-ice and ice-sheet systems. In the Southern Ocean, conventional satellite altimetry measurements are rare below the 66° parallel. Hydrodynamic models are thus useful tools to provide spatially continuous information about ocean tides. However, the accuracy of ocean tide models around the Antarctic continent is currently limited by the quality of bathymetry. Recent reprocessing of decade-long CryoSat-2 data has facilitated a new computation of bathymetry around Antarctica, bringing innovative information on bathymetry gradients. This, combined with new compilations of bathymetry, ice draft, coastline, and grounding line datasets in ice-shelf regions, allows improving models and knowledge of ocean tides in the Southern Ocean. We developed a new high-resolution tidal model that implements the improved bathymetry data and includes data assimilation of satellite-altimetry tidal retrievals computed from CryoSat-2, filling the gap between the 66°S-limited coverage of the TOPEX-Jason suite missions and the Antarctic coast. Comparisons with tidal estimates derived from tide gauge measurements showed very good consistencies with an RMSE of 3 cm.

深海测量和海洋潮汐的知识在各个科学领域，特别是在极地地区，起着关键的作用。它的意义延伸到海洋环流模拟和理解海洋、海冰和冰盖系统的耦合动力响应。在南大洋，传统的卫星测高测量很少在平行66°以下。因此，水动力模型是提供有关海洋潮汐的空间连续信息的有用工具。然而，目前南极大陆周围海洋潮汐模型的准确性受到水深测量质量的限制。最近对长达十年之久的CryoSat-2数据的再处理促进了南极洲周围测深的新计算，带来了有关测深梯度的创新信息。这与冰架区域的测深、冰流、海岸线和接地线数据集的新汇编相结合，可以改进南大洋海洋潮汐的模型和知识。我们开发了一种新的高分辨率潮汐模型，该模型实现了改进的测深数据，并包括从CryoSat-2计算的卫星测高潮汐检索数据同化，填补了TOPEX-Jason套件任务与南极海岸66°s有限覆盖范围之间的空白。与由验潮仪测量得出的潮汐估计值的比较显示出与RMSE为3厘米的非常好的一致性。

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引用次数: 0

The diversity, composition and functions of soil bacterial communities surrounding Syowa Station, East Antarctica, under different intensities of human disturbances 不同人为干扰强度下南极洲东部 Syowa 站周围土壤细菌群落的多样性、组成和功能

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101095

Shu-Kuan Wong , Satoshi Imura , Masaki Uchida , Kenichi Watanabe , Mizuho Mori , Sakae Kudoh

Since the establishment of Syowa Station over six decades ago, the study on the terrestrial bacterial community surrounding the station has been notably lacking and inadequately documented. Using the latest sequencing technology, we revealed the soil bacterial composition from soil samples collected from the surrounding of the station. In doing so, we also assessed the effect of human disturbances brought upon by different activities in the proximity of the station, in contrast to those in less human interference and pristine areas. Our results show that human activities near the main station facilities, especially within the 100-m range, visibly changed the structure and functions of the soil microbial community. Areas with high levels of human disturbances displayed a decrease in both microbial diversity and richness, accompanied by a lower count of unique amplicon sequence variants (ASVs) compared to regions with intermediate and low human disturbances. Moreover, higher proportions of functions related to hydrocarbon degradation were also predicted from samples collected within this area. In contrast, soil microbial communities from intermediate and low human disturbances samples have higher proportions of bacterial groups and functions consistent with those in undisturbed natural habitats.

自Syowa站建立60多年来，对该站周围陆生细菌群落的研究明显缺乏，文献记载也不充分。利用最新的测序技术，我们从站周围收集的土壤样本中揭示了土壤细菌组成。在此过程中，我们还评估了监测站附近不同活动所带来的人为干扰的影响，并与人为干扰较少和原始地区的影响进行了对比。结果表明，人类活动在主要站点设施附近，特别是在100 m范围内，明显改变了土壤微生物群落的结构和功能。与中度和轻度人为干扰地区相比，高水平人为干扰地区的微生物多样性和丰富度均有所下降，同时独特扩增子序列变异（asv）数量也较低。此外，从该区域内收集的样品中还预测了与碳氢化合物降解相关的较高比例的功能。中、低人为干扰土壤微生物群落的菌群比例较高，功能与未受人为干扰的土壤微生物群落基本一致。

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引用次数: 0

Role of atmospheric and oceanic processes on interannual summertime (2016–2017) decrease of sea ice in the Antarctic regions of the Southern Ocean 大气和海洋过程对南大洋南极地区夏季海冰年际减少（2016-2017 年）的作用

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101108

Ananthu Pradeep , A. Mukherjee

In this article, the interannual variability of sea ice in the Antarctic sea ice regions between 2013–2018 is studied using a global ocean sea ice coupled model and satellite observation. The numerical model reasonably well simulates satellite observed interannual variability of sea ice concentration (SIC) and sea surface temperature (SST) in the Antarctic regions of Southern Ocean during all four austral seasons; summer (December–February), autumn (March–May), winter (June–August), and spring (September–November).

A comparison of satellite and model shows that, during last two decades between 2001–2020, summertime of 2016–2017 had the lowest (highest) SIC (SST) across the Antarctic sea ice regions. Mixed layer heat budget analysis has been performed to comprehend how thermodynamic processes affect changes in SIC and SST in the Antarctic sea ice regions. The strong positive net atmospheric heat flux and the negative ocean vertical entrainment during summertime of 2016–2017 resulted in increased SST compared to other years, which lead to decreased SIC during above years. Also, loss of sea ice during summertime of 2016–2017 in the Antarctic sea ice regions are linked with significant decrease of wind stress magnitude and increase of wind stress curl.

本文利用全球海洋海冰耦合模式和卫星观测，研究了 2013-2018 年间南极海冰区海冰的年际变化。数值模式合理地模拟了卫星观测到的南大洋南极海冰区夏季（12 月-2 月）、秋季（3 月-5 月）、冬季（6 月-8 月）和春季（9 月-11 月）海冰浓度（SIC）和海面温度（SST）的年际变化。

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引用次数: 0

Dynamics of pollutants accumulation in the snow of an urban agglomeration 城市群积雪中污染物积累的动态变化

IF 1.5 4区地球科学 Q3 ECOLOGY

Polar Science

Pub Date : 2024-12-01 DOI: 10.1016/j.polar.2024.101072

Aleksandr Yu Kozhevnikov , Nikita A. Shutskiy , Semen L. Shestakov , Alexey V. Malkov , Dmitriy E. Lahmanov

Snowpack properties allow using snow as a convenient indicator of atmospheric air pollution, precipitation, and eventually soil pollution. There is a high probability of trace elements and organic pollutants accumulation on the snow cover acting as the deposit matrix. In this study, we analyzed the dynamics of the content of metals (Ca, Mn, Fe, Zn, Sr, Pb and Ba) in filtered and unfiltered samples and the content of polyaromatic hydrocarbons (18 basic PAHs) in weekly snow sampling in the city and nearby. The obtained results were collated with the content of the same contaminants in the snow sampled layer by layer at the end of the season (layer thickness was 0.1 m). In result of the study, we concluded that the sampling should be carried out right after the precipitation for the purpose of atmospheric pollution estimation, because most of heavy metals migrate through the snow layers into soil cover and get lost by the end of the season. The organic pollutants, such as PAHs, are also lost. The sampling of snow during the whole season allows identifying the global and local sources of contaminants released into the atmosphere.

积雪特性允许使用雪作为大气空气污染、降水和最终土壤污染的方便指标。微量元素和有机污染物极有可能作为沉积基质在积雪上积累。本研究分析了过滤和未过滤样品中金属（Ca、Mn、Fe、Zn、Sr、Pb和Ba）含量的动态变化，以及城市及附近地区每周雪样中多芳烃（18种碱性多环芳烃）含量的动态变化。将所得结果与季末逐层取样的雪（层厚为0.1 m）中相同污染物的含量进行对比。研究结果表明，为了估算大气污染，应在降水结束后立即进行采样，因为大部分重金属通过雪层迁移到土壤覆盖层中，并在季末丢失。有机污染物，如多环芳烃，也会消失。在整个季节对雪进行采样，可以确定释放到大气中的污染物的全球和当地来源。

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引用次数: 0