Originally Posted by
cyccommute
There’s “yabut” in there. GPS is slower in measuring elevation so it varies more when moving. Barometric pressure altitude measurements are quicker but they are influenced by more factors…temperature and pressure, as you pointed out…which can lead to errors. Both have about the same amount of error in measurement. If the phone is depending on the GPS signal for altitude, the errors might propagate faster because of the slow measurement
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GPS is slower in measuring elevation so it varies more when moving
I am not familiar with this "slowness in measurement" error with GPS.
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Both have about the same amount of error in measurement.
That's not my understanding. GPS errors are typically considerably larger, because they exist and are roughly the same
on every measurement. Barometric errors creep in as the pressure drifts over several hours, which is why it's a good idea to re-calibrate elevation periodically at a known position.