Three Dimensional Computer Simulations of Maxwell Equations and Snow Microstructures for Active and Passive Microwave Observations of Snow on Sea Ice in a Changing Climate

麦克斯韦方程和雪微观结构的三维计算机模拟，用于主动和被动微波观测气候变化下海冰上的雪

• 批准号: 1503917
• 负责人: Leung Tsang
• 金额: $ 28.36万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1503917&HistoricalAwards=false
• 关键词: Three; Dimensional; Computer; Simulations; Maxwell

Snow cover plays a key role in Arctic sea ice processes, and it has thinned significantly in recent decades. In winter, it insulates sea ice from cold air temperatures, slowing sea ice growth. In spring-summer, snow albedo exerts a control on solar heat absorbed by the sea ice and underlying ocean, impacting ice melt processes. Thus, snow thickness, distribution, and density, can moderate the recovery of the sea ice pack or exacerbate its loss. Airborne and satellite remote sensing are used to monitor snow depth over sea ice. Interpretation of the remotely sensed microwave signals requires accurate models of how the microwaves interact with the snow. This project will develop electromagnetic models that relate the microwave signatures quantitatively to physical parameters of snow. It will contribute to STEM workforce development by providing support for the training of a graduate student. The computer code for the model will be made publicly available and provide a resource for the Arctic science community.The proposed project will improve the extraction of snow parameters from airborne and spaceborne observations through the modeling of the interaction between snow particles and electromagnetic waves in the microwave region. In particular, the project will generate 3D simulations of the solution to Maxwell's equations in the presence of 3D snow microstructure. Results will be applied to the analysis of active and passive microwave remote sensing data of snow over sea ice. Three-dimensional computer simulations of microstructures of snow that resemble that of real snow will be performed on High Performance Computing (HPC) systems to compute scattering and emission of snow covering sea-ice. The use of large scale high performance computations will permit the simulations to be run over relatively large spatial domains.

积雪在北极海冰过程中起着关键作用，近几十年来已经明显变薄。在冬季，它使海冰与冷空气温度隔绝，减缓了海冰的生长。在春夏季，积雪反照率对海冰和下伏海洋吸收的太阳热量起控制作用，影响冰融化过程。因此，雪的厚度、分布和密度可以减缓海冰的恢复或加剧其损失。航空和卫星遥感被用来监测海冰上的雪深。对遥感微波信号的解释需要精确的微波与雪相互作用的模型。该项目将开发电磁模型，将微波特征定量地与雪的物理参数联系起来。它将通过为研究生的培训提供支持，促进STEM劳动力的发展。该模型的计算机代码将向公众开放，并为北极科学界提供资源。该项目将通过模拟微波区雪粒子与电磁波的相互作用，改进机载和星载观测中雪参数的提取。特别是，该项目将在三维雪微观结构存在的情况下生成麦克斯韦方程组解的三维模拟。研究结果将应用于海冰积雪的主动和被动微波遥感数据分析。将在高性能计算（HPC）系统上对雪的微观结构进行三维计算机模拟，以计算覆盖海冰的雪的散射和发射。大规模高性能计算的使用将允许在相对较大的空间域上运行模拟。