MODELLING THE EARTH'S ROTATION  
Tabulated models for the Earth orientation / rotation parameters variations
Useful constants | IERS Conventions | Models and Softwares | Tidal variations in LOD

Compilation done by Ch. Bizouard (Observatoire de Paris) and
Laura Fernandez (Facultad de Ciencias Astronomicas y Geofisicas La Plata Argentina).

Send your comments to christian.bizouard[at]obspm.fr.
Permanent improvements and adds
Earth rotation component
  • Tidal gravitational
  • Oceanic forcing
  • Atmospheric forcing
  • Empirical astrometric models forcing (moon-sun-planets)
NUTATIONS (> 2 days) click-here
(nutation models)
POLAR MOTION

from 100 years to 6 hours
click-here
UT1 / LOD

from 100 years to 6 hours
click-here
Useful constants geodesy, gravimetry, physics, astronomy : click here
IERS CONVENTIONS
IERS CONVENTIONS CENTER
IERS CONVENTIONS 1996
IERS CONVENTIONS 2003
Models, constants related to Earth's rotation and adopted by IERS (conventions 2003 is an up-date of conventions 1996).
Astronomical and geophysical models with associated softwares
SOFA: Standards of Fundamental Astronomy (Astronomical Sofware packages recommanded by IAU)
MODELS CORRESPONDING SOFTWARE
Earth orientation matrix based on Nutation model IAU 2000 Coordinate transformation from the terrestrial reference system (TRS) to the celestial reference system (CRS) using the IAU 2000 precession-nutation model Non Rotating Origin algorithm
Partial derivatives with respect x,y, UT1, X,Y : nro_partialderiv.f
Nutation model IAU 1980    
     
Conversion celestial pole offsets UAI 1980 - UAI 2000 Package of subroutines in order to convert the IAU 1980 celestial pole offsets (dpsi,deps) into the IAU 2000 celestial pole offsets (dpsi,deps,dX,dY) and reciprocally, based upon SOFA matrix transformation.
uai2000.package
readme

Contact : christian.bizouard[at]obspm.fr
Correction for the effect of zonal tides in UT1, LOD and angular velocity, consistent with the IERS Conventions 2000.
tver2000.f
Contact: christian.bizouard[at]obspm.fr
Diurnal and semidiurnal polar motion/UT1 - IERS conventions 2000 : PM caused by oceanic tides (71 waves) and lunisolar torque (10 waves)
Interpolation of IERS polar motion and UT1 time series, with restoration of diurnal and semi diurnal variations (developped by Observatoire de Paris/NEOS) interp.f,
interp.readme
Contact: christian.bizouard[at]obspm.fr
TAI - UTC Computation of the difference TAI-UTC from 1 January 1961 untill now. Very usefull for converting UT1-UTC into UT1-TAI.

mjd_to_TAIUTC.f
sauts_de_seconde.txt
Contact: christian.bizouard[at]obspm.fr

  Compute the civil date from the (modified) Julian Date and reciprocally caldat.f
Contact: gérard.francou@obspm.fr