No wind ? No way !
Like somebody said it is temperature inversion
layer preventing the wind entering ice surface. Those pipes are from big paper factories at Oulu, Finland and are at least 50m tall. On the sound track there are many kiters present with most flying LEIs and they are OMG.
During winter time we get nice thermal layer effects, like in the morning we have wind 8m/s, then suddenly thermal layer kicks in and wind drops to 0m/s at surface but from smoke you can see that >50m there is wind. After 30 minutes wind comes back to surface.
As a proof that at kite flying altitude there is no wind you can fly with the kite 360 degree circle. If there was wind even 1m/s (3.6km/h = almost normal walking speed) you could not fly the kite 360 circle by walking, because you need to have 3.6km/h speed component downwind when the kite is upwind to remove effect of 1m/s wind. The guy is walking steady round circle and kite flies 360.
I've also flown 360 kite circles, with foils it is possible. I am yet to see a video where Infinity prototype V10 is doing 360 circle flown by PMU.
Here is my helmet cam video which is shake stabilized. My 12DLX S3 starts from where the wind window was before thermal layer kicked in. At the background you can see the LEIs grounded.
And believe me (because I've done it) that on this circumstance it is possible to kite home with my kites. You need hard snow and skis (instead of snowboard) to kick in little speed to yourself and small pull on front lines and TRUE light wind capable kite carries you home!