The Crow Asks: Can you explain these odd contrails?

Last week near sunset I noticed some contrails about (as typically in the YXU at this time of year). But check these out. If you look at the photos you’ll see that “above” each trail the trail looks normal but “below” it is a series of round, puffy clouds, not unlike cirrocumulus clouds. Definitely not billow shaped clouds ones would expect from some kind of gravity wave interaction.

Can anyone tell me is this an altitude affect, dynamics, or is it a function of the type of airplane engine which emitted the water vapour?

Colorado Fire Smoke Over London, Canada?

Here’s some uncalibrated lidar measurements from the night of 21 June, 2013 which show what appears to be a faint smoke layer around 13 km. I did a quick and dirty run of HYSPLIT and the trajectories go back to Colorado in about 2 days. They descend about 25% of their initial height, e.g. as they go across the prairies they drop, for instance, from 10,000 m to 7,500 m elevation.

Uncalibrated returns from The University of Western Ontario’s Purple Crow Lidar, shows an apparent thin smoke layer around 13 km altitude. Full size image available here.