State-Dependent Response of the Polar Cap Index and High Latitude Ground Magnetic Fields to Solar Wind Coupling

极地盖指数和高纬度地面磁场对太阳风耦合的状态相关响应

• 批准号: 0425320
• 负责人: Robert McPherron
• 金额: $ 18万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-15 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0425320&HistoricalAwards=false
• 关键词: State; Dependent; Response; Polar; Cap

Funds are provided to quantify the dependence of the polar cap index (PC) on solar wind parameters, and thereby to determine the best functional form for PC, by calculating response filters based on singular value decomposition theory. At present, PC values are derived by using a scheme that aims to force agreement, on average, between PC and the solar wind motional electric field. Preliminary examination of the derivation scheme has revealed problems in how PC is defined. These problems may actually degrade the usefulness of the index in research studies and in an operational sense as a space weather forecasting or nowcasting tool. In addition, PC will be used to estimate the level of solar wind driving force that leads to polar cap potential drop saturation and determine the relative contributions of Hall and field-aligned currents to polar magnetic field disturbance. An improved and consistent definition of PC, as is sought in this research, should allow improved nowcasting and short-term forecasting of space weather events known to interfere with radio communication, radars, and low-orbiting and geostationary satellites.

通过计算基于奇异值分解理论的响应滤波器，量化极冠指数(PC)对太阳风参数的依赖关系，从而确定PC的最佳函数形式。目前，PC值是通过一种方案得出的，该方案旨在强制PC和太阳风运动电场之间的平均一致性。对派生方案的初步审查揭示了如何定义PC的问题。这些问题实际上可能会降低该指数在研究研究中以及在业务意义上作为空间天气预报或即刻预报工具的作用。此外，PC还将用于估计导致极帽电位降饱和的太阳风驱动力水平，并确定霍尔电流和场向电流对极磁场扰动的相对贡献。正如本研究所寻求的那样，改进和一致的PC定义应该能够改进对已知干扰无线电通信、雷达以及低轨道卫星和地球同步卫星的空间天气事件的即时预报和短期预报。