Effect in atmosphere-ocean changes reflected by frequent large breakups of landfast ice and ice shelf in the Antarctic

南极陆地冰和冰架频繁大规模破裂所反映的大气-海洋变化的影响

• 批准号: 15510015
• 负责人: USHIO Shuki
• 金额: $ 1.22万
• 依托单位: National Institute of Polar Research
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15510015/
• 关键词: Antarctic; sea ice; interannual variation; ice navigation; fast ice; pack ice; glacier ice tongue; ice shelf; 衛星リモートセンシング

Antarctic fast-ice variation has been investigated using satellite images and ship's ice navigation logs, focusing on breakup phenomena in Lutzow-Holmbukta (Lutzow-Holm Bay). Although spatio-temporal scales for breakup events vary somewhat for each event, their commencement is generally in autumn and almost always in the same region. Specifically, the 1997/98 breakup event occurred over a wide area and continued for a long time after the initial breakup. Since then, breakups have repeated until 2004, and a total of 20 annual events have been detected since 1980. Moreover, information from icebreaker navigation logs shows that unstable fast-ice conditions frequently occurred in the 1980s and after the late 1990s. From the analysis of surface meteorological data and the offshore pack-ice distribution, anomalously shallow snow-cover depths and a peculiar retreat pattern of the ice edge are found to be factors that favor fast-ice breakup. The pack ice distribution controls the propagation … More of ocean swell inside the bay ; encroaching swells are likely to mechanically disintegrate fast-ice field during autumn prior to the annual formation of the protective pack-ice cover to the north. Less snow cover also leads to fast-ice weakening as the melt season progresses and broken floes are then transported offshore by prevailing southerly winds.In this way, the patterns of landfast-ice breakup and formation/persistence likely exert an important influence on the dynamics and thermodynamics of outlet glaciers and also the inland ice sheet. To promote this study, field measurements linked with satellite remote sensing are required to detect glaciological responses to landfast-ice stability in the form of the changing flow characteristics of floating ice tongues and the elevation/thickness distributions of inland drainage basins. Satellite imagery with high spatial resolution is much useful for quantification of the tongue movement of the Shirase Glacier that flows inside Lutzow-Holmbukta. Less

利用卫星图像和船舶冰导航日志研究了南极固定冰的变化，重点关注卢佐夫-霍尔姆布克塔（卢佐夫-霍尔姆湾）的破裂现象。尽管每个事件的分手事件的时空尺度有所不同，但它们通常开始于秋季，并且几乎总是在同一地区。具体来说，1997/98年的分手事件发生范围较广，并且在初次分手后持续了很长一段时间。此后，直至2004年，解体现象不断重复，自1980年以来，每年共发现20起事件。此外，破冰船航行日志的信息显示，不稳定的固冰状况在20世纪80年代和90年代后期频繁发生。通过对地面气象资料和近海浮冰分布的分析，发现异常浅的积雪深度和特殊的冰缘后退模式是有利于冰快速破裂的因素。浮冰分布控制着海湾内海浪的传播；秋季，在北部浮冰保护层每年形成之前，侵蚀性的涌浪可能会机械地分解固定冰场。随着融化季节的进行，积雪减少也会导致冰快速减弱，破碎的浮冰随后被盛行的南风输送到近海。通过这种方式，陆地冰的破裂和形成/持续模式可能对出口冰川和内陆冰盖的动力学和热力学产生重要影响。为了促进这项研究，需要与卫星遥感相结合的现场测量来检测冰川对固冰稳定性的响应，其形式是浮冰舌变化的流动特征和内陆流域盆地的高程/厚度分布。具有高空间分辨率的卫星图像对于量化 Lutzow-Holmbukta 内部流动的 Shirase 冰川的舌状运动非常有用。较少的

项目成果

海氷研究の現状と将来展望-南極リュツォ・ホルム湾の海氷変動機構の解明を目指して-.

海冰研究现状与未来展望——旨在阐明南极吕措霍尔姆湾海冰波动机制。

• 发表时间: 2003
• 期刊: 月刊海洋 (総特集「海氷研究の最前線-衛星リモートセンシング・現地観測からのアプローチ」 35・10
• 作者: K.Kikawada;M.Uruga;T.Oi;T.Honda;牛尾収輝
• 通讯作者: 牛尾収輝

「しらせ」砕氷航行データが示す南極リュツォ・ホルム湾定着氷の年々変化

Shirase 破冰导航数据显示南极洲 Lütso-Holm 湾固冰的逐年变化

• 发表时间: 2004
• 期刊: 南極資料 48・3
• 作者: K.Hirose;T.Honda;S.Yagishita;Y.Igarashi;M.Aoyama;牛尾収輝
• 通讯作者: 牛尾収輝

過去50年間にわたる南極リュツォ・ホルム湾定着氷の変動

过去50年南极柳措-霍尔姆湾固冰的变化

• 发表时间: 2006
• 期刊: 雪氷 68・4(発表予定)(査読済み)
• 作者: 牛尾収輝;若林裕之;西尾文彦
• 通讯作者: 西尾文彦

牛尾収輝: "海氷研究の原状と将来展望-南極リュツォ・ホルム湾の海氷変動機構の解明を目指して-"月間海洋 総特集「海氷研究の最前線-衛星リモートセンシング・現地観測からのアプローチ. 35巻・10号. 675-680 (2003)

Haruki Ushio：《海冰研究现状与未来展望——旨在阐明南极柳措-霍尔姆湾海冰涨落机制》——《每月海洋专题》海冰研究前沿——来自卫星遥感和实地观察方法。第 35 卷，第 10 期。675-680 (2003)

Sea ice variations in Lutzow-Holmbukta, Antarctica, derived from ice navigation log during the period of 1983-2002

南极洲 Lutzow-Holmbukta 海冰变化，源自 1983 年至 2002 年期间冰航行日志

• 发表时间: 2004
• 期刊: Proceedings of the Fourteenth (2004) International Offshore and Polar Engineering Conference
• 作者: T.Ichii;K.Mahapatra;M.Sakai;D.Inagake;Y.Okada;Shuki Ushio;Shuki Ushio
• 通讯作者: Shuki Ushio