年度极运动的变化及其与钱德勒波动的关系
Songyun Wang1, Clark R Wilson1,2, Jianli Chen3,4,5
1Center for Space Research, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78759.
概括
地球 地球 地球 地球 地球 地球
科学领域:
- 地质物理学 地质物理学
- 气候科学 气候科学
- 天文学 天文学
背景情况:
- 极地运动表现出显著的每年激发幅度.
- 了解这种激发的年复一年变化对于地球的旋转动态至关重要.
研究的目的:
- 量化逐年升级年度激发幅度的年对年变化.
- 调查这种变化的气候来源.
- 评估这种变异性在令人兴奋的钱德勒波动中的作用.
主要方法:
- 对1900年之前的观测数据进行分析,以得出一个 Prograde Annual Amplitude Modulation (PAAM) 时间序列.
- 利用气候模型和观测数据来识别激发源.
- 频率分析以调查振荡及其对钱德勒波动的影响.
主要成果:
- 在PAAM时间序列中发现了一个明显的多年,近六年的振荡 (SYO).
- 发现大气过程是SYO的主要贡献者.
- SYO对钱德勒波动激发有显著的贡献,占其功率的一半以上.
结论:
- 观测证据证实了地球气候和旋转动态的六年振荡.
- 该SYO调节年度激发,影响钱德勒摇摆动态.
- 年度激发的年复一年变化是钱德勒波动的主要驱动因素.
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