From: A candidate secular variation model for IGRF-13 based on MHD dynamo simulation and 4DEnVar data assimilation
Iteration#
\(\alpha_{S}\) (factor for \({\mathbf{R}}_{S}\))
[\(\times 1.4 \times 10^{4}\)]
\(\alpha_{UW} \left( {{\text{factor for }}{\mathbf{R}}_{U} ,{\mathbf{R}}_{W} } \right)\)
[\(\times 300\)]
1
1.0
2
0.2
3
0.1
4
0.02
5
0.001