Magnetic declination, sometimes called magnetic variation, is the angle between magnetic north and true north. As the earth's magnetic field varies over time, the positions of the north and south magnetic poles gradually change. This map displays historical isogonic lines (where declination has the same value) and magnetic poles (green dot) calculated for the years 1590-2020. Red lines are positive (east of north), blue lines are negative (west of north) and the green line is agonic, or zero declination. Watch how the magnetic pole wanders over time.
Model description:
Years 1590-1890: calculated from the gUFM model
Years 1900-2020: calculated from the IGRF
Years 1890-1900: a smooth transition was imposed between models
