Isogonic-Map1

Isogonic map of the continental United States as of 2015. Red lines on the map indicate positive declination (east). Blue lines on the map indicate negative declination (west). The green line running through the Midwest is the agonic line, which has 0° declination. This is a screenshot taken from the NOAA Declination Map Viewer.

Isogonic map of the continental United States as of 2015. Red lines on the map indicate positive declination (east). Blue lines on the map indicate negative declination (west). The green line running through the Midwest is the agonic line, which has 0° declination. This is a screenshot taken from the NOAA Declination Map Viewer.