Relationship of physical and mechanical properties of sea ice during the freeze-up season in Nansen Basin

IF 3.8 2区工程技术 Q1 ENGINEERING, CIVIL Cold Regions Science and Technology Pub Date : 2024-10-28 DOI:10.1016/j.coldregions.2024.104353

Vegard Hornnes , Evgenii Salganik , Knut Vilhelm Høyland

{"title":"Relationship of physical and mechanical properties of sea ice during the freeze-up season in Nansen Basin","authors":"Vegard Hornnes , Evgenii Salganik , Knut Vilhelm Høyland","doi":"10.1016/j.coldregions.2024.104353","DOIUrl":null,"url":null,"abstract":"<div><div>Sea-ice properties, such as porosity and strength, can have significant spatial variability at small scales. Quantifying this variability may give better estimates of the ice properties and their interrelation. Additionally, correlating in situ ice strength measurements and ice properties, including porosity, may improve understanding of the factors influencing ice strength. This paper presents measurements of sea-ice properties and strength on first- and second-year sea ice during the GoNorth expedition to the Arctic Ocean in October 2022. In situ borehole indentation measurements were co-located with measurements of physical properties, and the meter-scale variability of the physical properties and strength was investigated. Bulk density values found from hydrostatic weighing were 911 ± 5 kg m<sup>−3</sup> for first-year and 904 ± 5 kg m<sup>−3</sup> for second-year ice, with significantly less uncertainty than density values from the mass/volume method or from freeboard/draft measurements. The second-year ice was relatively saline, with a mean bulk salinity of 3.1 ± 0.5, and the ice was desalinated in the upper and lower 0.2 m. The bulk gas fraction in the second-year ice was 2.5 ± 0.5 %, similar to the first-year ice gas fraction of 2.8 ± 0.5 %. Gas fractions up to 6.5 % were observed in the second-year ice without any obvious correlation with the brine fraction. The second-year ice had larger spatial variability in thickness, porosity, grain structure, and ice strength compared to the first-year ice. Variability in bulk density and gas fraction were similar for first- and second-year ice, as the larger variability was mostly seen below the upper 0.4 m of the second-year ice. The borehole strength was 26.0 ± 4.4 MPa for first-year and 41.0 ± 12.1 MPa for second-year ice. There were indications that the total microporosity at indentation depth was related to in situ borehole strength (<span><math><msup><mi>R</mi><mn>2</mn></msup></math></span> = 0.82), and that brine volume was the most influential parameter. The relative variability in the local microporosity in the second-year ice (0.43) was greater than the relative variability in borehole strength (0.27), while the opposite was true for the first-year ice (0.09 versus 0.17).</div></div>","PeriodicalId":10522,"journal":{"name":"Cold Regions Science and Technology","volume":"229 ","pages":"Article 104353"},"PeriodicalIF":3.8000,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cold Regions Science and Technology","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0165232X24002349","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CIVIL","Score":null,"Total":0}

引用次数: 0

Abstract

Sea-ice properties, such as porosity and strength, can have significant spatial variability at small scales. Quantifying this variability may give better estimates of the ice properties and their interrelation. Additionally, correlating in situ ice strength measurements and ice properties, including porosity, may improve understanding of the factors influencing ice strength. This paper presents measurements of sea-ice properties and strength on first- and second-year sea ice during the GoNorth expedition to the Arctic Ocean in October 2022. In situ borehole indentation measurements were co-located with measurements of physical properties, and the meter-scale variability of the physical properties and strength was investigated. Bulk density values found from hydrostatic weighing were 911 ± 5 kg m⁻³ for first-year and 904 ± 5 kg m⁻³ for second-year ice, with significantly less uncertainty than density values from the mass/volume method or from freeboard/draft measurements. The second-year ice was relatively saline, with a mean bulk salinity of 3.1 ± 0.5, and the ice was desalinated in the upper and lower 0.2 m. The bulk gas fraction in the second-year ice was 2.5 ± 0.5 %, similar to the first-year ice gas fraction of 2.8 ± 0.5 %. Gas fractions up to 6.5 % were observed in the second-year ice without any obvious correlation with the brine fraction. The second-year ice had larger spatial variability in thickness, porosity, grain structure, and ice strength compared to the first-year ice. Variability in bulk density and gas fraction were similar for first- and second-year ice, as the larger variability was mostly seen below the upper 0.4 m of the second-year ice. The borehole strength was 26.0 ± 4.4 MPa for first-year and 41.0 ± 12.1 MPa for second-year ice. There were indications that the total microporosity at indentation depth was related to in situ borehole strength (

R^{2}

= 0.82), and that brine volume was the most influential parameter. The relative variability in the local microporosity in the second-year ice (0.43) was greater than the relative variability in borehole strength (0.27), while the opposite was true for the first-year ice (0.09 versus 0.17).

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

南森盆地冻结期海冰物理和机械特性的关系

海冰特性，如孔隙度和强度，在小尺度上会有很大的空间变化。量化这种变异性可以更好地估计冰的特性及其相互关系。此外，将原位冰强度测量结果与包括孔隙度在内的冰属性联系起来，可以加深对影响冰强度的因素的理解。本文介绍了 2022 年 10 月在北冰洋 GoNorth 考察期间对第一年和第二年海冰的特性和强度进行的测量。现场钻孔压痕测量与物理性质测量同时进行，并对物理性质和强度的米级变化进行了研究。通过静力学称重发现，第一年冰的体积密度值为 911 ± 5 kg m-3，第二年冰的体积密度值为 904 ± 5 kg m-3，其不确定性明显小于质量/体积法或自由板/透气度测量法得出的密度值。第二年冰的盐度相对较高，平均体积盐度为 3.1 ± 0.5，冰的上部和下部 0.2 米处脱盐。在第二年冰层中观测到的气体分数高达 6.5%，但与盐水分数没有明显的相关性。与第一年冰相比，第二年冰在厚度、孔隙度、晶粒结构和冰强度方面的空间变化较大。第一年和第二年冰的容积密度和气体组分的变异性相似，因为较大的变异性主要出现在第二年冰的上层 0.4 米以下。第一年冰的钻孔强度为 26.0 ± 4.4 兆帕，第二年冰的钻孔强度为 41.0 ± 12.1 兆帕。有迹象表明，压痕深度的总微孔与现场钻孔强度有关（R2 = 0.82），而盐水体积是影响最大的参数。二年冰局部微孔的相对变异性（0.43）大于钻孔强度的相对变异性（0.27），而一年冰的情况正好相反（0.09 对 0.17）。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

Cold Regions Science and Technology 工程技术-地球科学综合

CiteScore

7.40

自引率

12.20%

发文量

209

审稿时长

4.9 months

期刊介绍： Cold Regions Science and Technology is an international journal dealing with the science and technical problems of cold environments in both the polar regions and more temperate locations. It includes fundamental aspects of cryospheric sciences which have applications for cold regions problems as well as engineering topics which relate to the cryosphere. Emphasis is given to applied science with broad coverage of the physical and mechanical aspects of ice (including glaciers and sea ice), snow and snow avalanches, ice-water systems, ice-bonded soils and permafrost. Relevant aspects of Earth science, materials science, offshore and river ice engineering are also of primary interest. These include icing of ships and structures as well as trafficability in cold environments. Technological advances for cold regions in research, development, and engineering practice are relevant to the journal. Theoretical papers must include a detailed discussion of the potential application of the theory to address cold regions problems. The journal serves a wide range of specialists, providing a medium for interdisciplinary communication and a convenient source of reference.