Linking sea ice deformation to ice thickness redistribution using high-resolution satellite and airborne observations
Linking sea ice deformation to ice thickness redistribution using high-resolution satellite and airborne observations
复制标题
利用高分辨率卫星和机载观测将海冰变形与冰厚度重新分布联系起来
DOI：
10.5194/tc-15-2167-2021
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
W. Dierking
中科院分区：
文献类型：
--
作者：
Luisa von Albedyll;C. Haas;W. Dierking
抽象的。2018年冬末，一个不寻常的大型潜热冰间湖在格陵兰海岸以北因冻结和收敛而打开并关闭。闭幕式展示了一个自然但约束良好的全尺寸冰变形实验。我们观察到的关闭和变形内的冰间湖与卫星合成孔径雷达（SAR）图像和测量的累积效应的动态和热力学冰的增长与航空电磁（AEM）冰厚度调查1个月后开始关闭。在此期间，强大的冰收敛减少了2.5倍的面积重新冻结冰穴。AEM调查显示，1个月大的冰的平均厚度和模态厚度分别为1.96 ± 1.5 m和1.1 m。我们表明，这是在密切的协议与模拟的热力学增长和动态增厚预计从冰间湖面积减少在这段时间。我们发现显着差异的形状的冰厚度分布（ITDs）在不同地区的再冻结冰穴。这些密切对应于不同的变形历史的调查冰，我们重建拉格朗日冰漂移轨迹的逆时间顺序。我们构建了冰漂移轨迹从定期网格化，高分辨率的漂移场计算的SAR图像和提取变形来自漂移场沿着的轨迹。结果表明，收敛和厚度变化之间的线性比例关系，符合冰厚重分布理论。我们发现ITD尾部的e折叠与冰所经历的总变形之间成比例。最后，我们开发了一个简单的，体积守恒的模型来推导动态冰厚度变化的拉格朗日轨迹和高分辨率的SAR漂移和变形场的组合。该模型具有1.4公里的空间分辨率和重建厚度剖面与AEM观测合理的协议。模拟的ITD类似于观察到的ITD的主要特征，包括模式，e折叠，和半高全宽。因此，我们证明了高分辨率的SAR变形观测能够产生现实的冰厚度分布。
Abstract. An unusual, large, latent-heat polynya opened and then closed by freezing and convergence north of Greenland's coast in late winter 2018. The closing presented a natural but well-constrained full-scale ice deformation experiment. We observed the closing of and deformation within the polynya with satellite synthetic-aperture radar (SAR) imagery and measured the accumulated effects of dynamic and thermodynamic ice growth with an airborne electromagnetic (AEM) ice thickness survey 1 month after the closing began. During that time, strong ice convergence decreased the area of the refrozen polynya by a factor of 2.5. The AEM survey showed mean and modal thicknesses of the 1-month-old ice of 1.96 ± 1.5 m and 1.1 m, respectively. We show that this is in close agreement with modeled thermodynamic growth and with the dynamic thickening expected from the polynya area decrease during that time. We found significant differences in the shapes of ice thickness distributions (ITDs) in different regions of the refrozen polynya. These closely corresponded to different deformation histories of the surveyed ice that we reconstructed from Lagrangian ice drift trajectories in reverse chronological order. We constructed the ice drift trajectories from regularly gridded, high-resolution drift fields calculated from SAR imagery and extracted deformation derived from the drift fields along the trajectories. Results show a linear proportionality between convergence and thickness change that agrees well with the ice thickness redistribution theory. We found a proportionality between the e folding of the ITDs' tails and the total deformation experienced by the ice. Lastly, we developed a simple, volume-conserving model to derive dynamic ice thickness change from the combination of Lagrangian trajectories and high-resolution SAR drift and deformation fields. The model has a spatial resolution of 1.4 km and reconstructs thickness profiles in reasonable agreement with the AEM observations. The modeled ITD resembles the main characteristics of the observed ITD, including mode, e folding, and full width at half maximum. Thus, we demonstrate that high-resolution SAR deformation observations are capable of producing realistic ice thickness distributions.
估计从卫星图像和浮标阵列反演冰速度和变形参数的统计误差
DOI：
10.5194/tc-14-2999-2020
发表时间：
2020
期刊：
The Cryosphere
影响因子：
--
作者：
Dierking, Wolfgang;Stern, Harry L.;Hutchings, Jennifer K.
通讯作者：
Hutchings, Jennifer K.
影响因子：
3.2
作者：
Losch, Martin;Menemenlis, Dimitris;Hill, Chris
通讯作者：
Hill, Chris