Interannual variability of summer sea ice thickness in the Siberian and central Arctic under different atmospheric circulation regimes
Interannual variability of summer sea ice thickness in the Siberian and central Arctic under different atmospheric circulation regimes
复制标题
不同大气环流状况下西伯利亚和北极中部夏季海冰厚度的年际变化
DOI：
10.1029/1999jc000088
复制
发表时间：
2001
影响因子：
--
通讯作者：
H. Eicken
中科院分区：
文献类型：
--
作者：
C. Haas;H. Eicken
在1993年，1995年和1996年夏天，在西伯利亚和北极海中部海冰厚度的广泛钻孔和电磁感应测量揭示显着的年际变化。在拉普捷夫海，1995年和1996年第一年最小和最大模态冰厚分别为1.25米和1.85米。冰厚与冰广相关，冰广在1995年8月达到创纪录的最低值，1996年远高于平均值。这些差异的强度和位置的夏季气旋大气环流模式影响冰平流和表面融化的解释。从1995年部署的漂流浮标和卫星雷达后向散射数据，第一和第二年的冰制度划定。1993年、1995年和1996年第一年冰后向散射系数的差异可以通过水平冰面粗糙度的差异来解释。研究了1995 ~ 1996年冰厚的拉格朗日演变。虽然厚度分布的形状没有显着变化，平均（模态）冰厚度的冰原增加1.80米（1.25米），1995年至2.86米（2.25米），在1996年。1996年第二年冰的厚度分布与1991年获得的跨极漂移下游水平多年冰的厚度分布基本一致。1996年，北冰洋卡拉海和拉普捷夫海的平均水平冰厚度分别随纬度增加0.23和0.16 m deg−1。
Extensive drill hole and electromagnetic induction measurements of sea ice thickness in the Siberian and central Arctic Seas in the summers of 1993, 1995, and 1996 reveal significant interannual variability. In the Laptev Sea, minimum and maximum modal first-year ice thicknesses amounted to 1.25 and 1.85 m in 1995 and 1996, respectively. Ice thickness correlates with ice extent, which reached a record minimum in August 1995 and was well above average in 1996. These differences are explained by the strength and location of a summer cyclonic atmospheric circulation pattern affecting both ice advection and surface melt. From drifting buoys deployed in 1995 and satellite radar backscatter data, first- and second-year ice regimes are delineated. Differences in first-year ice backscatter coefficients between 1993, 1995, and 1996 are explained by differences in level ice surface roughness. The Lagrangian evolution of ice thickness between 1995 and 1996 is studied. While the shape of the thickness distribution does not change significantly, the mean (modal) ice thickness of the ice field increases from 1.80 m (1.25 m) in 1995 to 2.86 m (2.25 m) in 1996. The thickness distribution of second-year ice in 1996 closely agrees with that of level multiyear ice downstream in the Transpolar Drift obtained in 1991. In 1996, mean level ice thickness increases at 0.23 and 0.16 m deg−1 with latitude in the Kara and Laptev Sea sectors of the Arctic Ocean, respectively.