Firn Model Intercomparison Experiment (FirnMICE)
Firn Model Intercomparison Experiment (FirnMICE)
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DOI：
10.1017/jog.2016.114
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发表时间：
2017-02
影响因子：
3.4
通讯作者：
J. Lundin;C. Stevens;R. Arthern;C. Buizert;A. Orsi;S. Ligtenberg;S. Simonsen;E. Cummings;R. Essery;W. Leahy;P. Harris;M. Helsen;E. Waddington
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文献类型：
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作者：
J. Lundin;C. Stevens;R. Arthern;C. Buizert;A. Orsi;S. Ligtenberg;S. Simonsen;E. Cummings;R. Essery;W. Leahy;P. Harris;M. Helsen;E. Waddington
冷干雪和积雪的演化在冰川学中占有重要地位，然而，其致密化规律的物理表述仍是一个活跃的研究课题。我们迫使八个积雪致密化模型和一个季节性雪模型在六个不同的实验中，通过施加温度和累积速率边界条件的阶跃变化;所有的边界条件都被选择来模拟寒冷干燥环境中的积雪致密化。虽然参与模型的预期应用各不相同，但它们描述的是相同的物理系统，原则上应产生相同的解决方案。积雪模型都产生合理的深度密度剖面，但在稳态和瞬态模式的模型输出不同的冰芯和测高研究感兴趣的数量。这些差异表明，积雪致密化模型是不正确的或不完全代表的物理过程。我们定量地描述了不同模型的结果之间的差异。例如，我们发现深度积分孔隙度是不太可能推断出的信心，从一个积雪模型，以更好地在稳定状态下在一个特定的网站与已知的积累速度和温度超过2米。积雪模型比对试验可以为未来的模型提供一个基准，为量化模型的不确定性提供依据，并指导未来的积雪致密化模拟方向。
ABSTRACT Evolution of cold dry snow and firn plays important roles in glaciology; however, the physical formulation of a densification law is still an active research topic. We forced eight firn-densification models and one seasonal-snow model in six different experiments by imposing step changes in temperature and accumulation-rate boundary conditions; all of the boundary conditions were chosen to simulate firn densification in cold, dry environments. While the intended application of the participating models varies, they are describing the same physical system and should in principle yield the same solutions. The firn models all produce plausible depth-density profiles, but the model outputs in both steady state and transient modes differ for quantities that are of interest in ice core and altimetry research. These differences demonstrate that firn-densification models are incorrectly or incompletely representing physical processes. We quantitatively characterize the differences among the results from the various models. For example, we find depth-integrated porosity is unlikely to be inferred with confidence from a firn model to better than 2 m in steady state at a specific site with known accumulation rate and temperature. Firn Model Intercomparison Experiment can provide a benchmark of results for future models, provide a basis to quantify model uncertainties and guide future directions of firn-densification modeling.