Collaborative Research: CMG: Microstructural Controls on Transport Processes in Geophysical Systems

采用数学与数值模拟、室内实验、现场实验和三维数据可视化技术相结合的方法，确定海冰微观孔隙结构对海冰宏观热力学和流体输运性质的影响。这项工作代表了数学家、冰川学家和计算机科学家之间的合作。各种数学方法，包括晶格和连续渗流表示，来模拟不规则三维介质的体积性质，将应用于具有微尺度盐水包裹体之间不同程度连通性的冰。现场和实验室实验，包括冰样品的核磁共振成像和x射线成像，将与结果数据的现代三维渲染相结合，以提供有关这种连通性变异性的定量和定性信息，特别是作为冰温度的函数。模型预测的宏观渗透率和热导率将与实验测量的输运性质进行比较。通过与新西兰维多利亚大学的J. Fry博士的合作以及学生的研究项目，为海冰运输开发的模型将扩展到流体通过岩石的迁移和气体通过冰川的扩散。后者是从冰芯中捕获的气泡解释古大气成分的一个重要因素。该项目还包括大量的培训和外联工作，对研究生和本科生进行实地考察，在小学和中学进行课堂演示和实验。

A combination of mathematical and numerical modeling, laboratory experiments, field experiments, and three-dimensional data visualization techniques will be applied to the problem of determining the influence of the microscale pore structure of sea-ice on the macroscopic thermodynamic and fluid transport properties of such ice. The work represents a collaboration between a mathematician, a glaciologist and a computer scientist. A variety of mathematical approaches, including both lattice and continuum percolation representations, to modeling the bulk properties of irregular three-dimensional media will be applied to ice with varying degrees of connectivity between microscale brine inclusions. Field and lab experiments, including MRI and X-ray imaging of ice samples, will be combined with modern three-dimensional rendering of the resulting data to provide quantitative and qualitative information about the variability of such connectivity, particularly as a function of ice temperature. Model predictions of macroscopic permeability and thermal conductivity will be compared to experimentally measured transport properties. Through a collaboration with Dr. J. Fry at Victoria University, New Zealand, and student research projects, the models developed for transport in sea-ice will be extended to fluid migration through rock and the diffusion of gas through glacial firn. The latter is an important factor in the interpretation of paleo-atmospheric composition from bubbles trapped in ice-cores. The project also includes a substantial amount of training and outreach, with field work for graduate and undergraduate students, and classroom demonstrations and experiments in elementary and secondary schools.