Which North Pole does Santa Claus live at?

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Which North Pole does Santa Claus live at?

• True North
• The earths axis of rotation
• Magnetic North
• Where your compass points
• Grid North
• Where the UTM grid lines point to.

2
True v.s. Magnetic North

• Depending on where you areThe angle between true
  and magnetic north will be different.

3
What is the difference here?

• Fruitvale Ave. is aligned with True North.
• So are the edges of parking lots 4 5.
• Lets go take a bearing along the edge of lot 4
  and see what we get

4

• ltparking lot declination diagramgt

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USA Declination Map
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World Declination Map
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Declination Diagrams
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Declination changes over time

• Here in Northern California it changes by about
  1 every 20 years.
• The declination shown on your topo map may be out
  of date.
• What about declination displayed by my GPS?
• It probably correct as of the date of manufacture.

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Declination Calculatorat www.ngdc.noaa.gov
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Local Anomalies

• May be as much as 90 degrees
• 3-4 degrees is common
• North of Kingston, Ontario 90 of anomalous
  declination.
• Kingston Harbor, Ontario 16.3 W to 15.5 E of
  anomalous declination over two kilometers (1.2
  miles) magnetite and ilmenite deposits.
• Savoff, Ontario (50.0 N, 85.0 W). Over 60 of
  anomalous declination.    
• Ramapo Mountains, northeastern New Jersey iron
  ore compass rendered useless in some areas.
• Near Grants, New Mexico north of the Gila
  Wilderness area Malpais lava flows compass
  rendered useless.  

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Figuring out the adjustmentfrom magnetic to true

• My compass needle is pointing to the east of true
  north by 16

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Magnetic to True

• To adjust my compass to point to true north, I
  need to turn me bezel 16 to the west.
• That is the same as adding 16 to my magnetic
  bearing.

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Declination

• East Declination
• Add declination to convert from Magnetic to True
• Subtract declination to convert from True to
  Magnetic
• West Declination
• Subtract declination to convert from Magnetic to
  True
• Add declination to convert from True to Magnetic

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Two Schools of Thought

• Set it and forget it
• Adjust for the declination in your compass.
• All bearings will be true.
• No conversion required to use it on a map.
• Dont forget to check the setting occasionally.
• Dont forget to change it when you go somewhere
  else.
• Set it to 0, and always think about it
• All bearings will be magnetic.
• Conversion to true is necessary for map work.
• Works with all compasses.
• You are more likely to remember how declination
  works.

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No bearing is complete without the word True or
Magnetic following it.

• Dont make people guess, say it!

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Inclination or Dip

• The earths magnetic field is not always parallel
  to the surface.
• Thus compass needles need to be balanced
• A compass needle balanced for the northern
  hemisphere may rub the inside of the capsule in
  the southern hemisphere.
• Some compasses are designed for worldwide use.