13.5 Compass Mode -
Magnetic Declination
13.4 Compass Mode -
Applications of the Compass
13.6 Compass Mode -
Magnetic Declination Compensation
C h e c k y o u r p o s i t i o n b y B a c k w a r d B e a r i n g
Directions
!
Spot two distant identifiable landmarks such as
mountains, light-house, fort and building of your
current position, for example the mountain A and B.
!
Check out the backward bearing directions of
mountain A and B of your current position, such as
135 from mountain A and 270 from mountain B.
!
Use a ruler to draw the line 135 on the map which
starting from the mountain A. Draw the lines 270
on the map which starting from the mountain B.
!
Your current position on the map will be the
intersection point (point A) of the lines 135 and
270
Check the Trek Course Correct
!
During a trekking, the Watch can keep your course
correct. For example, the correct trail starts from
point A and finishes at point E as it is drawn on the
adjacent map.
!
Mark the points (identifiable landmarks) 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
map.
!
Find 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 ).
!
During the trekking, make sure that the heading
direction is 315 from point A to point B. Performing
the similar checking in other sections of the trail.
IMPORTANT:
If you are in doubt of the directions and
positions of the trail, consulting the park administration
office before starting the trekking.
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Magnetic Declination Compensation
!
To compensate an object's bearing by subtract
w e s t e r l y ( W ) m a g n e t i c d e c l i n a t i o n o r a d d
e a s t e r l y ( 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
magnetic bearing.
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!
Example 1
: Westerly magnetic declination 23
and the compass needle points 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 compass needle points 278 .
!
TB = MB + E. While MB = 278 ; E = 22
!
TB = 278 + 22
!
TB = 300
!
The true bearing will be 300 .
!
The Watch allows you compensate the compass
b e a r i n g a t a p l a c e w h e r e t h e m a g n e t i c
declination is either Westerly declination or
Easterly declination.
!
Check the coming chapters "Calibrating the
Compass" for more detail of the setting.
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
13.7 Compass Mode -
Magnetic Declination at Major Cities
No. Country/Place Major City Declination
33 Netherlands
Amsterdam
1-W
34 New Zealand
Wellington
22-E
35 Norway
Oslo
0
36 Pakistan
Islamabad
2-E
37 Philippines
Manila
1-W
38 Portugal
Lisbon
5-W
39 Russia
Moscow
9-E
40 Singapore
Singapore
0
41 South Africa
Cape Town
23-W
42 Spain
Madrid
3-W
43 Sweden
Stockholm
3-E
44 Switzerland
Bern
0
45 Taiwan
Tai-pei
3-W
46 Thailand
Bangkok
0
47 UAE
Abu Dhabi
1-E
48 United Kingdom
London
3-W
49 United States
Washington, DC
10-W
50
Juneau
25-E
51
Phoenix
12-E
52
Little Rock
2-E
53
Sacramento
16-E
54
Denver
10-E
55
Atlanta
4-W
56
Honolulu
10-E
57
Boston
16-W
58
Saint Paul
2-E
59
Jackson
1-E
60
Santa Fe
10-E
61
Oklahoma City
6-E
62
Salem
18-E
63
Harrisburg
11-W
64
Salt Lake City
14-E
No. Country/Place
Major City Declination
1
Afghanistan
Kabul
2-E
2
Australia
Canberra
12-E
3
Austria
Vienna
2-E
4
Bahrain
Manama
2-E
5
Bangladesh
Dhaka
0
6
Belgium
Brussels
1-W
7
Brazil
Brasilia
19-W
8
Canada
Ottawa
14-W
9
Chile
Santiago
5-E
10
Beijing
6-W
11 China
Hong Kong
2-W
12 Costa Rica
San Jose
0
13 Cuba
Havana
3-W
14 Czech Republic
Prague
2-E
15 Denmark
Copenhagen
1-E
16 Egypt
Cairo
3-E
17 Finland
Helsinki
6-E
18 France
Paris
1-W
19 Germany
Berlin
1-E
20 Greece
Athens
3-E
21 Hungary
Budapest
4-E
22 India
New Delhi
1-E
23 Indonesia
Jakarta
1-E
24 Israel
3-E
25 Italy
Rome
1-E
26 Japan
Tokyo
7-W
27 Jordan
Amman
3-E
28 Kenya
Nairobi
1-E
29 Korea
Seoul
7-W
30 Malaysia
Kuala Lumpur
1-E
31 Mexico
Mexico City
6-E
32 Nepal
Kathmandu
0
China
Jerusalem
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 compensation setting for
M a g n e t i c D e c l i n a t i o n . C h e c k t h e c o m i n g s e c t i o n
"
for more detail.
Magnetic Declination Information
!
Most topographic maps include a small arrow which
shown magnetic north pole and or the magnetic
declination information.
!
For the benefit of user, this user m a n u a l i n c l u d e s t h e
magnetic declination for some major cities. Check the
coming section 'Magnetic Declination at Major Cities' for
more detail.
!
For those cities whose names are not included in the list, you
can input that city's latitude and longitude into one of the
below magnetic declination calculation websites (as at 28
Oct 2005) to get the magnetic declination:
1) http://gsc.nrcan.gc.ca/geomag/index_e.php
2)
The Magnetic North Pole which is slightly different from
the True North Pole.
This 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.
For serious compass user or who intends to perform
accurate navigation, compass must be adjusted for
magnetic declination.
Calibrating the compass - Magnetic Declination Mode"
http://www.ngdc.noaa.gov/seg/geomag/declination.shtml
