Originally Posted by
terrymorse
The Garmin Connect website (connect.garmin.com) has an "elevations correction" feature you can use after the fact to correct the errors in recorded elevation data.
From my most recent ride (82.23 mi), elevation gain:
Without elevation corrections (barometric elevation): 6,726 ft
With elevation corrections (elevation from "professional surveys"): 8,089 ft
It's hard to know which of these is "correct". I was riding in hilly terrain, so any GPS inaccuracies could have put me up a steep slope or down a ravine.
I have always been curious about the Garmin elevation correction feature, which is switched off by default. My Edge 530 is very consistent with elevation gain. On my local loop it’s always within about 20m. On specific event routes where the elevation gain is known it always reports very close to the advertised figure. So I have never felt the need to switch on the correction feature.