Table 1 CIY4 parameterization
Field source/effect | # Parms | Description | ||
|---|---|---|---|---|
Core/lithosphere | 13,368 | Spatial: geographic spherical harmonic (SH) \(N_{\max }=100\) | ||
Temporal: order 4 B-splines SV, 6 month knot spacing from 2013.9 to 2018.0, epoch 2015.0, up to \(N_{\max }=16\) | ||||
\(M_2\) tidal | 2736 | Spatial: geographic SH \(N_{\max }=36\) | ||
Temporal: period of 12.42060122 hours, Greenwich fixed phase | ||||
Ionosphere/induced | 5520 | Spatial: quasi-dipole (QD) frame, underlying dipole SH \(N_{\max }=60\), \(M_{\max }=12\) | ||
Temporal: annual, semiannual, 24, 12, 8, and 6 h periodicities with \(F_{10.7}\) scaling plus induction via a priori 3D conductivity model (“1D + oceans”) and infinite conductor at depth | ||||
Magnetosphere/induced | 165,252 | Magnetosphere Spatial: dipole SH \(N_{\max }=1\) Temporal: discretized in 1 h bins | ||
Induced Spatial: dipole SH \(N_{\max }=1\) Temporal: discretized in 1 h bins | ||||
OHM biases | 465 | One vector bias for each station in local spherical system | ||
VFM-CRF alignment | 1350 | Three XYZ-type Euler angles every 10 days for each satellite | ||
Total | 188,691 | − | ||