Estimating the sources of global sea level rise with data assimilation techniques
Estimating the sources of global sea level rise with data assimilation techniques
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DOI：
10.1073/pnas.1117683109
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发表时间：
2012-04
期刊：
影响因子：
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通讯作者：
Carling Hay;E. Morrow;Robert E Kopp;J. Mitrovica
中科院分区：
文献类型：
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作者：
Carling Hay;E. Morrow;Robert E Kopp;J. Mitrovica
快速融化的冰盖产生了海平面（SL）变化的独特几何形状或指纹。因此，SL观测网络，原则上，可以用来推断融水通量的来源。我们概述了一种形式主义，基于修改后的卡尔曼平滑，使用验潮站观测估计全球SL变化的个人来源。我们还报告了一系列基于合成SL数据的检测实验，探索从SL记录中提取源信息的可行性。卡尔曼平滑技术迭代计算格陵兰冰盖（GIS）和南极西部冰盖（WAIS）融化的最大似然估计在每个时间步，它容纳数据的差距，同时也允许估计的非线性趋势。我们的综合试验表明，当所有验潮记录用于分析，它应该是可能的估计GIS和WAIS融化率大于0.3和0.4毫米的等效海平面上升，每年分别。我们还实现了一个多模型卡尔曼滤波器，使我们能够严格考虑SL变化及其相关的不确定性的额外贡献。多模型滤波器使用72个冰川均衡调整模型和3个海洋动力学模型来估计这些过程的最可能模型。我们的结论是，我们修改后的卡尔曼平滑程序提供了一个强大的方法来推断融化率在一个变暖的世界。
A rapidly melting ice sheet produces a distinctive geometry, or fingerprint, of sea level (SL) change. Thus, a network of SL observations may, in principle, be used to infer sources of meltwater flux. We outline a formalism, based on a modified Kalman smoother, for using tide gauge observations to estimate the individual sources of global SL change. We also report on a series of detection experiments based on synthetic SL data that explore the feasibility of extracting source information from SL records. The Kalman smoother technique iteratively calculates the maximum-likelihood estimate of Greenland ice sheet (GIS) and West Antarctic ice sheet (WAIS) melt at each time step, and it accommodates data gaps while also permitting the estimation of nonlinear trends. Our synthetic tests indicate that when all tide gauge records are used in the analysis, it should be possible to estimate GIS and WAIS melt rates greater than ∼0.3 and ∼0.4 mm of equivalent eustatic sea level rise per year, respectively. We have also implemented a multimodel Kalman filter that allows us to account rigorously for additional contributions to SL changes and their associated uncertainty. The multimodel filter uses 72 glacial isostatic adjustment models and 3 ocean dynamic models to estimate the most likely models for these processes given the synthetic observations. We conclude that our modified Kalman smoother procedure provides a powerful method for inferring melt rates in a warming world.