Where Do I Find The Correct Declination For My Area So I Can Set My Wristop Computer; Effect Of Air Temperature On Altitude Measurement - Suunto Vector User Manual

6.5.2 Where do I find the correct declination for my area so I can
set my Wristop Computer?
Local declination, either E or W, is usually marked on maps with either one-degree or half-degree accuracy.
6.6 EFFECT OF AIR TEMPERATURE ON ALTITUDE
MEASUREMENT
The atmospheric pressure means the weight of air mass above the observer: at a higher altitude there is less
air than at a lower altitude. The principle of an altimeter is to measure the different air pressure between
different altitudes.
The air weight is affected by the outside temperature. Consequently the air pressure difference between two
altitudes is also dependant on temperature.
The altitude calculation of Wristop Computer is based on the air pressure at certain normal temperatures. Each
altitude has a definitive normal temperature. The normal temperatures at each altitude are presented in table 1.
Altitude (m) Altitude (ft)
above sea level above sea level
0
200
400
600
800
1000
1200
1400
1600
Temperature (C)
0 15.0
656 13.7
1312 12.4
1969 11.1
2625
3281
3937
4593
5250
42
Temperature (F)
59.0
56.7
54.3
52.0
9.8 49.6
8.5 47.3
7.2 45.0
5.9 42.6
4.6 40.3