SUUNTO Elementum Terra - Manual (Page 24)

Elementum Terra senses vertical movement and switches to measuring altitude,
when needed. When switching to measuring altitude, the maximum delay for
showing the updated altitude value is 59 seconds. When altitude is shown, it
is updated with a maximum delay of 10 seconds. The benefit of automatic
switching is that you do not have to remember to change between altitude
and air pressure measuring according to your movements as the watch does
it automatically for you.
3.4 At constant altitude
If you are at a constant altitude (less than 5 meters of vertical movement within
12 minutes), the watch interprets all pressure changes as weather changes.
The measurement interval is one minute. The altitude reading remains steady,
and if the weather changes, you will see changes in the sea level air pressure
reading. The barometric trend arrow changes if the change is significant (2 hPa
or more in 3 hours).
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