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9.5 Compass Mode -
Magnetic Declination
9.4 Compass Mode -
Applications of the Compass Display and Backward Bearing
9.6 Compass Mode -
Magnetic Declination Compensation
What is Magnetic Declination
The angular difference between Magnetic North Pole
and True North Pole is called magnetic declination. Its
amount (degrees and minutes) and direction (easterly
and westerly) depend on where you are in the world.
The Watch also includes a setting for Magnetic
Declination compensation. Check the chapter 9.6 and
9.10 for more detail on how to compensate Magnetic
Declination.
Magnetic Declination Information
Most topographic maps include a small arrow which
shown magnetic north pole and or the magnetic
declination information.
This manual also includes the magnetic declination for
some cities in chapter 9.7.
For the city which does not include in this manual,
please refer to the below online resource:
http://www.geolab.nrcan.gc.ca/geomag/mirp_e.shtml
http://www.ngdc.noaa.gov/seg/geomag/jsp/struts/calcD
eclination
+ The Magnetic North Pole which is slightly different from
the True North Pole.
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The Watch, like most magnetic compass, points to the
Magnetic North Pole. On the contrary, everything
measure from a map is related to the True North Pole.
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For serious compass user or whom intends to perform
accurate navigation, the Watch must be adjusted for
magnetic declination.
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Check the position by Backward Bearing
Spot two distant identifiable landmarks such as
mountains, light-house and building from your
current position. Let's use the mountain A and B
as the example.
Check out the backward bearing direction of
mountain A and B from your current position: 135
from mountain A and 270 from mountain B.
Draw the line 135 on the map which starting from
the mountain A, and draw another line 270 on the
map which starting from the mountain B.
Your current position on the map will be at the
intersection point (point A) of the lines 135 and
270
Check the Trek Course Correct
The Watch can keep your course correct during
trekking. Lets use the sample trail A-E on the
adjacent diagram to illustrate this application.
Mark the points where the trail turns its direction
or the trail branches its way, such as the point A,
B, C, D and E on the adjacent diagram.
Check out the bearing directions of point B from
point A (315 ), point C from point B (0 ), point D
from point C (225 ), and then point E from point D
(315 ).
Make sure that the heading direction is 315 in the
section A to B. Performing the similar checking
when trekking in the other trail sections.
IMPORTANT: If you are in doubt of the directions
and positions of the trail, consulting the park
administration office before starting the trek.
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8
8
+ 8
8
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8
8
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8 8
8
8
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8
Magnetic Declination Compensation
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To compensate an object's magnetic bearing
t o t r u e b e a r i n g : S u b t r a c t w e s t e r l y ( W )
magnetic declination or add easterly (E)
m a g n e t i c d e c l i n a t i o n w i t h t h e m a g n e t i c
bearing (MB).
+ 8
magnetic bearing 8
+ 8 8
+ 8 8
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8
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8
+
8
magnetic bearing 8
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8 8
+
8 8
+ 8
+ 8
Example 1 : Westerly magnetic declination 23
and the 323 .
TB = MB - W. While MB = 323 ; W =23
TB = 323 - 23
TB = 300
The true bearing will be 300 .
Example 2 : Easterly magnetic declination 22
and the 278 .
TB = MB + E. While MB = 278 ; E = 22
TB = 278 + 22
TB = 300
The true bearing will be 300 .
True North
Magnetic
Declination Magnetic
Declination
Magnetic
North
4110 m
2120 m
3120 m
point A
(starting point)
point B
A Sample Trail on a Map
point D
point E
(finish point)
point C
315
8
225
8
0 8
315 8
mountain B
Check Current Position By Backward Bearing
mountain A
270 8
135 8
point A
0
0
Compensate th e Bearin g
with Weste rly (W ) Magnetic Declin atio n
Compensate th e Bearin g
with Easte rly (E ) Magnetic Declin atio n
Tru e Bearin g (T B) =
Magneti c Bearin g (M B) - Weste rly Magneti c Decli nati on (W )
Tru e Bearin g (T B) =
Magneti c Bearin g (M B) + Easte rly Magneti c Decli nati on (E )
300
8 (T B) = 278 8 (M B) + 22 8 (E )
300 = (M B) - 23 (W )
8
(T B) 323
8 8
magnetic
declination
23 8 W
magnetic
declination
22 8 E
true
bearing
300
8
true
bearing
300
8
magnetic
bearing
323
8
magnetic
bearing
278
8
true north
0
8
true north
0 8
magnetic
north
magnetic
north
object B
object B
point A
point A
9.7 Compass Mode -
Magnetic Declination of Major Cities
No. Country/Place Major City Declination
1 Afghanistan Kabul +3E
2 Australia Canberra +12E
3 Austria Vienna +3E
4 Bahrain Manama +2E
5 Bangladesh Dhaka +0E
6 Belgium Brussels +0E
7 Brazil Brasilia -21W
8 Canada Ottawa -14W
9 Chile Santiago +3E
10 China Beijing -6W
11 China Hong Kong -2W
12 Costa Rica San Jose -1W
13 Cuba Havana -4W
14 Czech Republic Prague +3E
15 Denmark Copenhagen +3E
16 Egypt Cairo +4E
17 Finland Helsinki +8E
18 France Paris -1W
19 Germany Berlin +3E
20 Greece Athens +4E
21 Hungary Budapest +4E
22 India New Delhi +1E
23 Indonesia Jakarta +1E
24 Israel Jerusalem +4E
25 Italy Rome +2E
26 Japan Tokyo -7W
27 Jordan Amman +4E
28 Kenya Nairobi +0E
29 Korea Seoul -8W
30 Malaysia Kuala Lumpur +0E
31 Mexico Mexico City +6E
32 Nepal Kathmandu +0E
No. Country/Place Major City Declination
33 Netherlands Amsterdam +0E
34 New Zealand Wellington +22E
35 Norway Oslo +2E
36 Pakistan Islamabad +2E
37 Philippines Manila -1W
38 Portugal Lisbon -3W
39 Russia Moscow +10E
40 Singapore Singapore +0E
41 South Africa Cape Town -24W
42 Spain Madrid -2W
43 Sweden Stockholm +5E
44 Switzerland Bern +1E
45 Taiwan Tai-pei -4W
46 Thailand Bangkok -1W
47 UAE Abu Dhabi +2E
48 United Kingdom London -2W
49 United States Washington, DC -11W
50 United States Juneau +22E
51 United States Phoenix +11E
52 United States Little Rock +1E
53 United States Sacramento +14E
54 United States Denver +9E
55 United States Atlanta -4W
56 United States Honolulu +10E
57 United States Boston -15W
58 United States Saint Paul +1E
59 United States Jackson +0E
60 United States Santa Fe +9E
61 United States Oklahoma City +5E
62 United States Salem +16E
63 United States Harrisburg -11W
64 United States Salt Lake City +12E
NOTE: Since magnetic declination will be changed as going with time, recommend to check the update data from following site:
http://www.magnetic-declination.com/ & http://www.ngdc.noaa.gov/geomagmodels/Declination.jsp