Angular Momentum in the Earth System
Angular momentum is a fundamental conserved property of dynamic systems. Applying the principle of conservation of angular momentum to the Earth allows the causes of the observed changes in the rotation of the solid Earth to be investigated. After reviewing the application of this principle to the study of observed changes in the Earth’s rotation, it is used to investigate the influence of the atmosphere and oceans on the Earth’s rotation during 1985–1995. Although atmospheric winds are the dominate process causing the Earth’s rate of rotation to change on time scales of a few days to a few years, the redistribution of mass within the atmosphere and oceans is shown to be important in causing polar motion on these time scales.
KeywordsEarth rotation length-of-day polar motion atmospheric angular momentum oceanic angular momentum
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