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Positions, Distances, Directions, Compass

Compass Roses, Isogonic Lines, Local Magnetic Disturbance


  NOS    National Ocean Service (US)
  NIMA    National Imagery and Mapping Agency (US)
  IHO    International Hydrographic Organization

  Compass rose, normal pattern (smaller patterns of compass rose may be used)
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  True North compass rose
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  Isogonic lines
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click for larger image Local magnetic disturbance. Within the enclosed area, the magnetic variation may deviate from the normal by the value shown. click for larger image
click for larger image Local magnetic disturbance. Where the area affected cannot be easily defined, a legend only is shown at the position. click for larger image