Study of regional geomagnetic model of Fujian and adjacent areas based on 3D Taylor Polynomial model

Based on 256 measured geomagnetic vector data (Element D, I and H) in Fujian and adjacent areas, combined with the grid data of Global Land One-kilometer Base Elevation Project and the latest 12th International Geomagnetic Referenced Field (IGRF12) model, the regional geomagnetic model has been created by using three-dimensional (3D) Taylor Polynomial model. Through comparing the Root-Mean-Square error (RMS), geomagnetic distribution and residuals, two main conclusions are drawn: (1) Truncation degree N= 2 of 3D Taylor model basically produce the same calculation result as truncation degree N=6 of 2D Taylor model; (2) 3D Taylor model can calculate conveniently and has high precision, but it also has the probability of producing Runge Phenomenon. So, both calculation precision and boundary effect problem should be considered when determining truncation degree.