Models for polar motion oscillations  
Earth rotation component
Tidal gravitational forcing
(moon-sun-planets)
Oceans
Atmosphere
Empirical
astrometric
models
POLAR MOTION

> 2 days
 Brzezinski et al. 2002
  • Secular polar motion

  • Markowitz wobble

    		•
    POLAR MOTION

    Diurnal and subdiurnal*
    Brzezinski et al. 2002    		 tidal

  • IERS 1996

  • IERS 2000


    • non tidal

    de Viron et al. 2002

    		 Brzezinski et al. 2002  
    * For diurnal components only prograde polar motion by definition (for semidiurnal, terdiurnal or shorter than one day, prograde or retrograde components are possible).