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

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

Image Dec (001)
Year 1590

Image Dec (003)
Year 1592

Image Dec (005)
Year 1594

Gauss coefficients
image file of graph using gnuplot

Gauss Coefficients n=1,2