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Thread ID: 141574 2016-01-14 03:30:00 Magnetic declination in Auckland Tony (4941) PC World Chat
Post ID Timestamp Content User
1414466 2016-01-14 03:30:00 Here's one for the trampers and geographers.

I've seen a map of magnetic declination for the North Island, and the line that crosses Auckland is labelled "20.5". The line goes from south-west to north-east. Would that be described as "-20.5" or "+20.5"?
Tony (4941)
1414467 2016-01-14 04:24:00 "+" Zippity (58)
1414468 2016-01-14 04:26:00 It will be positive not negative, Tony.

en.wikipedia.org
KarameaDave (15222)
1414469 2016-01-14 04:37:00 If it was negative it would be 339.5 surely gary67 (56)
1414470 2016-01-14 08:04:00 Thanks folks. I did a bit more reading after I posted and realized the question was a bit meaningless, but yes it would be "+". Tony (4941)
1414471 2016-01-14 08:07:00 The magnetic declination (or magnetic variation) at any point on the earth is a property of the geomagnetic field defined as the angle that must be added or subtracted in converting between two kinds of directional information 1) the direction of the needle on a magnetic compass pointing at a location, magnetic heading and 2)the difference between the direction of the earth's lines of longitude, true track. The magnetic variation also increases (anti-clockwise) by 5° every 7 years.

A good way to remember adding and subtracting, is East-is least and West-is best.
WalOne (4202)
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