1. Cryospheric Excitation on the Earth's Chandler Wobble and Implications From a Warming World.
- Author
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Xu, CanCan, Chen, Fang, Huang, ChengLi, Zhou, YongHong, Shi, QiQi, Duan, PengShuo, and Xu, XueQing
- Subjects
CRYOSPHERE ,ALPINE glaciers ,FREE earth oscillations ,GREENLAND ice ,EARTH'S mantle ,ICE sheets ,EARTH (Planet) - Abstract
Leveraging Gravity Recovery and Climate Experiment mascon products spanning from April 2002 to September 2023, we, for the first time, ascertain the substantial influence of cryospheric mass variations on Earth's Chandler wobble (CW). Further, in contrast to traditional analysis conducted in the excitation domain, this study focuses on the polar motion domain and incorporates the wavelet analysis technique. Our findings reveal some intriguing phenomena: Between 2006 and 2020, the cryosphere contributed an average amplitude of approximately 4.85 mas to CW, equivalent to 5.05%, with its impact escalating to about 11 mas from 2018 to 2022, representing a fourfold rise in its contribution ratio to approximately 20%. This marked surge can be attributed to the more erratic glacier mass balance results from ongoing climate change. Moreover, there is a pronounced decrease in the CW signal post‐2018, which starkly contrasts with cryospheric contribution, suggesting a potential linkage to climate change yet warrants further investigation. Plain Language Summary: The Earth wobbles as it rotates like a spinning top. The largest of these wobbles, known as Chandler wobble, represents a free oscillation within the Earth's solid mantle. It undergoes subtle yet fluctuating temporal variations and is partially influenced by climate‐related fluid layers, including the atmosphere and ocean. This study explores the impact of the cryosphere—specifically the mass change in the Antarctic and Greenland ice sheets and global alpine glaciers—on the Chandler wobble. By analyzing gravity satellite (GRACE and its follow‐on) data from 2002 to 2023, we ascertain for the first time that cryospheric variations can substantially affect this wobble. Furthermore, employing advanced data analysis techniques enables us to unveil an intensified influence of the cryosphere in recent years that has captured our attention. Such intensification can be attributed to ongoing climate shifts, which led to increasingly irregular mass variations within the cryosphere. These findings enhance our understanding of how the cryosphere dynamics influence Earth's wobble, providing insights into the broader impacts of climate change. Key Points: For the first time, we confirm the substantial excitation of the cryosphere on Chandler wobbleUsing innovative approaches, we reveal its time‐varying contribution to Chandler wobble, which remarkably surged to about 11 mas by 2022We emphasize the growing impact of climate change on Chandler wobble, indicated by the increasingly erratic cryospheric dynamics [ABSTRACT FROM AUTHOR]
- Published
- 2024
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