GEM: Source Processes for Dispersive Shear Alfven Waves

GEM：色散剪切阿尔文波的源过程

• 批准号: 0602728
• 负责人: Christopher Chaston
• 金额: $ 27万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-15 至 2011-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0602728&HistoricalAwards=false
• 关键词: GEM; Source; Processes; Dispersive; Shear

Alfven waves appear to play an important role in the coupling of energy between the ionosphere and the magnetosphere. This project will examine the processes that produce these waves. Despite their importance rigorous identification of the source processes responsible for Alfven wave generation from in situ spacecraft observations are scarce. This project will employ observations from the ESA/NASA Cluster-II mission to identify these processes, evaluate the efficiency which energy is converted into dispersive Alfven waves by these processes, and quantify the energy that such processes deposit into the ionosphere. The waves affect the coupling between the magnetosphere and ionosphere in several ways: 1) they stimulate plasma outflow from the ionosphere, 2) they electrodynamically couple processes occurring in the outer magnetosphere to the ionosphere, and 3) they are driven by global-scale phenomena such as reconnection on the magnetopause and the Kelvin- Helmholtz instability in the low latitude boundary layer. The proposed research is important in the development of a Geospace General Circulation Model (GGCM) since it can provide empirically based laws describing the energy input from these processes into the magnetosphere and ionosphere which can be incorporated into global MHD codes. The proposed research promotes teaching, training and learning by providing support for a student researcher who will be involved in every aspect of the study.

阿尔芬波似乎在电离层和磁层之间的能量耦合中起着重要的作用。 这个项目将研究产生这些波的过程。 尽管它们的重要性，严格识别的源过程负责阿尔芬波生成从现场航天器观测是稀缺的。该项目将利用欧空局/美国航天局“探测器-II”使命的观测来确定这些过程，评价这些过程将能量转化为色散阿尔芬波的效率，并量化这些过程存款到电离层的能量。这些波以几种方式影响磁层和电离层之间的耦合：1）它们刺激电离层的等离子体流出，2）它们将外磁层中发生的过程电动耦合到电离层，以及3）它们由全球尺度的现象驱动，例如磁层顶的重联和低纬度边界层中的开尔文-亥姆霍兹不稳定性。拟议的研究是重要的地球空间大气环流模型（GGCM）的发展，因为它可以提供经验为基础的法律描述这些过程的能量输入到磁层和电离层，可以纳入全球MHD代码。拟议的研究促进教学，培训和学习，为学生研究员谁将参与研究的各个方面提供支持。