SUUNTO AMBIT - Manual (Page 56)

It is not possible to measure weather and altitude changes at the same time,
as both cause a change in the surrounding air pressure. Suunto Ambit senses
vertical movement and switches to measuring altitude, when needed. When
altitude is shown, it is updated with a maximum delay of 10 seconds.
If you are at a constant altitude (less than 5 meters of vertical movement within
12 minutes), Suunto Ambit interprets all pressure changes as weather changes.
The measurement interval is 10 seconds. The altitude reading remains steady
and if the weather changes, you will see changes in the sea level air pressure
reading.
If you are moving in altitude (more than 5 meters of vertical movement within
3 minutes), Suunto Ambit interprets all pressure changes as movements in
altitude.
Depending on which profile is active, you can access the Altimeter or
Barometer profile views with [View].
NOTE: When you are using the Automatic profile, barometer or altimeter
icons are not shown on the display.
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