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Predictability of the earth's polar motion
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Chao, B. F. |
| Copyright Year | 1984 |
| Description | A comprehensive, experimental study of the predictability of the polar motion using a homogeneous BIH (Bureau International de l'Heure) data set is presented. Based on knowledge of the physics of the annual and the Chandler wobbles, the numerical model for the polar motion is constructed by allowing the wobble periods to vary. Using an optimum base length of 6 years for prediction, this floating-period model, equipped with a non-linear least-squares estimator, is found to yield polar motion predictions accurate from 0.012 to 0.024 inches depending on the prediction length up to one year, corresponding to a predictability of 91-83%. This represents a considerable improvement over the conventional fixed-period predictor, which does not respond to variations in the apparent wobble periods. The superiority of the floating-period predictor to other predictors based on critically different numerical models is also demonstrated. |
| File Size | 816147 |
| Page Count | 22 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19840015923 |
| Archival Resource Key | ark:/13960/t9s22t87r |
| Language | English |
| Publisher Date | 1984-04-01 |
| Access Restriction | Open |
| Subject Keyword | Earth Resources And Remote Sensing Polar Wandering Geology Error Analysis Least Squares Method Time Series Analysis Transfer Functions Predictions Mass Distribution Oscillations Atmospheric Physics Mathematical Models Parameterization Periodic Variations Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
