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

将结合数学和数值模拟、实验室实验、野外实验和三维数据可视化技术来确定海冰的微尺度孔隙结构对这种冰的宏观热力学和流体传输特性的影响。这项工作代表了一位数学家、一位冰川学家和一位计算机科学家的合作。对于微尺度卤水包裹体之间具有不同程度连通性的冰，将应用各种数学方法，包括晶格和连续介质渗流表示法来模拟不规则三维介质的整体性质。现场和实验室实验，包括对冰样的核磁共振成像和X射线成像，将与产生的数据的现代三维绘制相结合，以提供关于这种连接的可变性的定量和定性信息，特别是作为冰温的函数。宏观渗透率和导热系数的模型预测将与实验测量的传输特性进行比较。通过与新西兰维多利亚大学的J·弗莱博士和学生研究项目的合作，为海冰中的运输开发的模型将扩展到岩石中的流体迁移和冰川积雪中的气体扩散。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，包括为研究生和本科生进行实地工作，以及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.