another cloud argument - from contrails

Today I saw a contrail left behind in the sky, with a clean beginning and ending. It was a white line segment against the dawn. Now one end might be because the pilot downshifted, but not both ends of the segment. So, logically, the sharp demarcation at one of the two ends must have been because of a sharp demarcation in the "evaporative environment". But there was noting visible around the contrail - and a pure change in humidity would not have a sharp boundary. 
Increasingly it seems the idea of an amorphous aerosol keeping stuck together because of a physical arrangement of different sized water particles - sounds like nonsense - unsupported by any evidence.

eDNA of atmospheric pseudomonas - velcro for water molecules

If you get a bunch of dead Pseudomonas you'll get a mat of organic polymers and water trapping proteins. Are not large masses of such stuff accumulating right now overhead?
My friend from Carlisle came up with the velcro phrase when I described it to him.

What I have been up to artistically

is colored pencil drawings. I call this kind a "quadrych"

This is a quadrych of a locust, dogwood, skyline, and plane.
Here is one of a tree line, from mid afternoon till dusk (woodpecker, dragonfly, sparrow, satellite). 

The rule for a quadrych is that, in some way, the lower right one should be over the top.

Cows make fog

The title is sort of a joke but contains a truth: I was driving to work admiring the fog hovering over the grass (clear sky above) and noticing it was denser over the marsh and low lying areas. No surprise there. But as I got onto 2A from Lexington Rd,  heading east with a cow field on the right and an open, mowed field on the left, it was surprising to see the fog rising thickly from the cow field and not at all from the mowed field.

It is likely the grass was not the same length or shape from mowing as from mooing (cows) but the difference in fog/no fog was stark enough to require a serious explanation - not a tossed off assumption about physical differences in the grass blade shapes. What to me is far more likely is that bacteria are needed for ground fog and there are lots of them in a cow field and not so much in a mowed field.