Elevation differences between Strava & Topofusion

[jmhix]

I helped put on a 100 miler this summer, my gps track of the race course made from preriding the race course or drawing the track in Topofusion yielded ~19k of climbing. The difference between the raw data and DEM corrected was less than 1k of climbing.

The racers tracks in Strava yield ~14k climbing. Which is correct and what is causing the error between the two? 5k seems to be a significant difference.

[ScottMorris]

Hi,

Good question.

Most likely the number in TF is too high.  Did you try loading the file up in Climbing Analysis to see what different numbers come up?  I would guess that the "Training Center" setting there might be closer to what Strava computes.  Basically they are probably filtering the data in a simple way.

On the other hand, it may just be a difference in GPS units -- many Edge units are known for inflating climbing numbers.

I haven't compared too many rides on Strava lately (haven't uploaded any for a couple years) but probably will this winter.  It'll be interesting to see how they compare.

Scott

[Seebonk]

The problem is that DEM data does not account for man's alteration of the topography (or bridges).  The uncorrected elevation from a barometric GPS should be taken as reality. 

https://docs.google.com/presentation/d/1G4oVsrmkbAGqcfWXtK3b8AwEjFEOXmo2VdMPf0umGlk/edit?usp=sharing