Results 31 to 40 of about 11,470 (155)
Chaotic oceanic excitation of low-frequency polar motion variability [PDF]
Earth System DynamicsStudies of Earth rotation variations generally assume that changes in non-tidal oceanic angular momentum (OAM) manifest the ocean's direct response to atmospheric forces.
L. Börger +7 more
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Polar motion of the triaxial nonrigid Earth and atmospheric excitation [PDF]
Geo-spatial Information Science, 2011 The present study aims to extend the traditional rotation theory of the rotational-symmetric Earth to the triaxial Earth. We re-formulate the Liouville equations and their general solutions for the triaxial nonrigid Earth and find that the traditional theory introduces some theoretical errors in modeling the excitation functions.
Wei Chen, Wenbin Shen
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Remote Sensing, 2022 Observations from the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions can be used to estimate gravimetric excitation of polar motion (PM), which reflects the contribution of mass changes in continental hydrosphere ...
Justyna Śliwińska +2 more
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Mass-related excitation of polar motion: an assessment of the new RL06 GRACE gravity field models
Earth, Planets and Space, 2018 The new Release-06 (RL06) Gravity Recovery and Climate Experiment (GRACE) gravity field solutions are evaluated by converting them into equatorial effective angular momentum functions (so-called excitation functions) for polar motion and comparing these ...
Franziska Göttl +2 more
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Polar ionospheric responses to solar wind IMF changes [PDF]
Annales Geophysicae, 2000 Auroral and airglow emissions over Eureka (89° CGM) during the 1997-98 winter show striking variations in relation to solar wind IMF changes. The period January 19 to 22, 1998, was chosen for detailed study, as the IMF was particularly strong and ...
Y. Zhang +8 more
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Geodesy and Geodynamics, 2017 At seasonal and intraseasonal time scales, polar motions are mainly excited by angular momentum fluctuations due to mass redistributions and relative motions in the atmosphere, oceans, and continental water, snow, and ice, which are usually provided by ...
Wei Chen +3 more
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Geophysical Research Letters, 2023 Climate model estimates show significant groundwater depletion during the 20th century, consistent with global mean sea level (GMSL) budget analysis. However, prior to the Argo float era, in the early 2000’s, there is little information about steric sea ...
Ki‐Weon Seo +7 more
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Remote Sensing, 2022 Due to the conservation of global angular momentum, polar motion (PM) is dominated by global mass redistributions and relative motions in the atmosphere, oceans and land water at seasonal time scales.
Haibo Liu, Yan Zhou, Jim Ray, Jiesi Luo
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Elliptic polarisation of the polar motion excitation
Journal of Geodesy, 2015 Because of its geophysical interpretation, Earth’s polar motion excitation is generally decomposed into prograde (counter-clockwise) and retrograde (clockwise) circular terms at fixed frequency. Yet, these later are commonly considered as specific to the frequency and to the underlying geophysical process, and no study has raised the possibility that ...
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On the Eigen‐Mode Excitation of Linear Oscillators and the Earth's Polar Motion [PDF]
Annalen der Physik, 2020 AbstractBy transforming a 1D second‐order linear oscillator into a 2D first‐order polar motion differential equation, it can be shown that the finite smoothness (i.e., the presence of jump in finite order derivatives) of the applied Newtonian forcing constitutes the sufficient and necessary condition for instantaneous excitation of free eigen‐mode ...
Ming Fang, Xinhao Liao, Xueqing Xu
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