Field Component: Inc
Gufm1 - Secular variation model for last 2ky (Jackson, Jonkers and Walter, 2000)

Contour of Component: Inc
image file of contour map using GMT

Image Inc (001)
Year 1590

Image Inc (003)
Year 1592

Image Inc (005)
Year 1594

Gauss coefficients
image file of graph using gnuplot

Gauss Coefficients n=1,2