基于三维Stokes流体耦合模型的冰盖演化特征并行有限元模拟研究

本研究项目将首先发展一套具有完全独立自主知识产权的基于大规模并行有限元方法的冰盖和冰川演化模式。该模式将基于完全三维斯托克斯流体方程，并与冰盖和冰川的热力学演化机制和冰层表面演化模型高度非线性耦合。通过标准的Benchmark验证数值模型和软件工具的正确性和可靠性。同时搜集和整理格陵兰岛和南极洲的冰盖、冰川数字影像和遥感科学数据及其关键性物性参数，利用有限元方法灵活高效的特点，通过多尺度非结构化网格生成技术和大规模并行求解技术的完美结合，对近似"真实"的格陵兰岛和南极洲冰盖和冰川的热力学演化过程进行数值模拟工作。揭示冰盖、冰川的破坏方式与冰层厚度、高程梯度及其它地球物理与气候条件的关系，开展有实际应用价值的短期冰演化与气候响应关系的分析研究，得出科学结论。研究成果将为我国可持续发展的环境规划和综合治理提供科学依据，同时也可以为我国政府官员参加年度哥本哈根全球气候变化大会的谈判提供科学借鉴。

We proposed a fully 3D coupled ice-sheet model to explore how ice-sheet changes under the realistic conditions. The governing equations for the thermo-mechanical ice-sheet modeling was formulated by a three-dimensional nonlinear full Stokes system for momentum, an advective-diffusive energy equation for temperature evolution, and a mass-conservation equation for ice thickness evolution. Parallel finite element solvers were employed to solve these respective sub-models. These solvers were integrated by a well-designed coupler for the exchanging of nonlinear parameters among them. By taking the full advantages of the up-to-date high-performance computing power, elaborately designed solvers for the coupled system were able to handle the large-scale realistic data from land and space-based observatories and laboratory experiments. Our implementation utilizes the high-quality nonuniform Centroidal Voronoi Delaunay triangulation (CVDT) meshing technology and existing parallel linear system solvers. The proficiency and scalability of our parallel solver were proved by some preliminary numerical tests. The potential impact of the project is very substantial. Direct and transformative.innovations resulting from the proposed project will greatly improve computational ice sheet model capabilities in the climate system modeling. In addition, this project will also offer a valuble information for the Chinese government representitives when they participate the anunnal The U.N. Climate Change conference in Copenhagen.