通过惠斯勒模式和ULF波来控制电离层TEC扰动的磁层控制
Yangyang Shen1, Olga P Verkhoglyadova2, Anton Artemyev1
1Department of Earth, Planetary, and Space Sciences University of California Los Angeles CA USA.
AGU advances
|November 28, 2024
概括
磁层超低频 (ULF) 波调节电子沉,导致电离层总电子含量 (TEC) 的变化. 这项研究将ULF调节的哨子模式波与高度dTEC联系起来,改善太空天气预报.
科学领域:
- 空间物理 空间物理
- 等离子体物理学的物理学
- 大气科学 大气科学
背景情况:
- 地球的电离层是一种弱电离等离子体,由于太阳,磁层和大气相互作用而表现出复杂的结构和变化.
- 离子层的变化,特别是总电子含量 (TEC) 扰动 (dTEC),对全球导航卫星系统 (GNSS) 应用和太空天气研究提出了挑战.
- 高度的dTEC变化与超低频 (ULF) 波有关,但根本的机制尚未完全理解.
研究的目的:
- 研究在高度处驱动dTEC调制的机制.
- 提供直接证据,将ULF波与电离层dTEC变化联系起来.
- 改进基于物理的dTEC建模和对磁层-离子层合的理解.
主要方法:
- 利用来自THEMIS航天器和位于阿拉斯加费尔班克斯的地面GPS接收器的磁联观测.
- 分析了总电子含量 (TEC) 和其扰动 (dTEC) 与ULF调制的哨声模式波数据一起.
- 在观察和建模的dTEC和波数据之间进行了交叉相关性分析和光谱分析.
主要成果:
- 发现了直接证据,dTEC调制是由ULF调制的哨声模式波引起的磁层电子沉驱动的.
- 观察到的峰值到峰值的dTEC振幅达到0.5 TECU,空间尺度为5-100公里.
- 在结合期中发现了模拟/观察的dTEC和ULF波之间的高交叉相关性 (0.8) 和光谱匹配.
结论:
- 阐明了从磁层波引起的电子沉中生成的高度dTEC.
- 解决了当前基于物理的dTEC建模中的一个重大差距.
- 通过ULF波增强了对磁层-离子层合的理解,并提高了离子层dTEC预测能力.
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