在地磁活动高的时期预测全球热层中性密度
Ehsan Forootan1, Saeed Farzaneh2, Mona Kosary2
1Geodesy Group, Department of Sustainability and Planning, Aalborg University, Rendburggade 14, 9000, Aalborg, Denmark. efo@plan.aau.dk.
Scientific reports
|November 21, 2023
概括
一个新的C/DA-NRLMSISE-00模型通过同化卫星数据来改善热层中性密度 (TND) 预测. 这提高了在地磁活动期间空间天气和轨道预测的准确性.
科学领域:
- 空间物理 空间物理
- 大气科学 大气科学
- 地质物理学 地质物理学
背景情况:
- 准确的热层中性密度 (TND) 估计对于理解上层大气合和精确的卫星轨道预测至关重要.
- 现有的TND模型面临由于简化结构和输入采样,特别是高地磁活动期间的局限性.
研究的目的:
- 通过将卫星测量集成到广泛使用的大气模型中来开发一个改进的TND模型.
- 为了提高TND预测的准确性,特别是在有重大地磁干扰的时期.
主要方法:
- 使用同步校准和数据同化 (C/DA) 算法将来自CHAMP,GRACE和Swarm卫星的TND数据集成到NRLMSISE-00模型中.
- 改进的模型,C/DA-NRLMSISE-00,用于在不同高度生成全球TND场.
- 使用未纳入同化中的TND数据,并与其他已建立的模型进行比较,进行了独立的验证.
主要成果:
- C/DA-NRLMSISE-00模型在多个卫星数据集和时间段 (2003-2020) 中显示了短期TND预测准确度的显著改善.
- 与GRACE,CHAMP,GOCE和Swarm卫星的沿轨TND估计相比,根平均平方误差平均减少了25%至63%.
- 该模型在高地磁活动时期显示出增强的性能,而其他模型则在此期间扎.
结论:
- C/DA-NRLMSISE-00模型在估计全球和多层次热层中性密度方面取得了重大进展.
- 这种改进的模型提供了更可靠的TND预测,有利于太空天气预报和卫星轨道的确定.
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