Superimposed-ice formation in summer on Ross Sea pack-ice floes
Superimposed-ice formation in summer on Ross Sea pack-ice floes
复制标题
夏季罗斯海浮冰上的叠冰形成
DOI：
10.3189/172756404781814168
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发表时间：
2004
影响因子：
2.9
通讯作者：
Roy H.R. Krouse
中科院分区：
文献类型：
--
作者：
T. Kawamura;M. Jeffries;J. Tison;Roy H.R. Krouse
摘要1999年1月，在南极洲罗斯海中部和东部的纳撒尼尔·B·帕尔默号游轮巡航期间，对南方夏季海冰过程进行了调查。研究了冰芯的晶体结构、~(18)O/~(16)O比值、冰芯的密度和盐度以及冰面上冰块的密度和盐度。栖息的冰块具有独特的多边形颗粒状(PG)晶体结构和非常负的同位素特征，这也是第一年浮冰顶部的层和多年浮冰表面以下的层的特征。PG冰是积雪融化并在冰雪表面重新冻结并直接在浮冰顶部形成的叠加冰。如果PG冰在冰面泛滥后被埋藏起来，由此产生的冰泥冻结，那么PG冰上方就会形成雪冰。讨论了叠加冰对浮冰表面质量平衡的贡献及其对天气和气候的影响。
Abstract Austral summer sea-ice processes were investigated in January 1999 during a cruise of the R.V. Nathaniel B. Palmer in the central and eastern Ross Sea, Antarctica. The crystal texture, 18O/16O ratios, density and salinity of ice cores and of ice blocks ‘perched’ on slush at the ice surface were studied. The perched ice blocks had a distinctive polygonal granular (PG) crystal texture and very negative isotope signature that were also characteristic of layers at the top of first-year floes and of layers ‘buried’ below the surface in multi-year floes. The PG ice is superimposed ice that results from melting in the snow cover and refreezing at the slush surface and directly on top of ice floes. If PG ice is buried after the ice surface floods and the resultant slush freezes, then snow ice forms above the PG ice. The contribution of superimposed ice to floe surface mass balance and some implications with respect to weather and climate are discussed.