Clouds are biofilms (rolled up)

There. Somebody had to take the extreme position.
If we are to suppose that bacteria have a role in precipitation, and add that the structure of clouds also looks like a fibrous mat, then we might as well also assume bacteria have a role in the formation of clouds - that the whole thing is bacterial, from start to finish.
Update: To put it more briefly: clouds are alive.

Contrails

Here is a picture illustrating contrail dissipation rate being influenced by clouds:

According to the site where I borrowed this, the contrails dissipate more slowly in higher humidity - namely when they are crossing clouds. They also mention some contrails spreading out and lasting a long time, blocking the sun. Do they become bacterial? It should be easy to find out.
Update: It turns out this is a well known phenomenon but because it is promoted by conspiracy theorist, no scientist dares discuss it. Persistent contrails are called "chemtrails" and are supposed to be a government plot. It is as if anywhere there is a conspiracy theory about the government you might get close to the truth by replacing the word "government" with the word "bacteria". Anyway, that is what happens when observant people do not have the tools of knowledge and science. But no excuse exists for those with those tools who do not use them on "suspect" observations. Of course in academics, it is about self preservation. 

Also:

Visual Impression as a Quantititative Measure

Why shouldn't one argue from visual impression of a material to its intrinsic properties? 

For example the shape of a bubble- or better yet the dynamic shape as the bubble emerges- is compatible with an elastic material or a material with surface tension (like gum or water), but incompatible with a granular isotropic material (like sand). So if you see a bubble shape (or a growing bubble) it is very fair to conclude the material is more like gum/water than like sand. Can you make the argument quantitatively? [I believe yes, as per best models/chi-squared]

Another example is sweeping up dog hair versus sweeping up sand. You sweep up dog hair and it starts to roll and form tubes. You sweep up sand and it stays sand. 

Why not have this be a legitimate way to say clouds are more like dog hair?

David Sands

I am happy to say the world's expert in bio-precipitation, David Sands, talked to me for 1/2 hour on the phone. I am wondering about inter-bacteria signalling, and later emailed: "If it starts to rain all at once, then the bacteria must be signalling each other." During the conversation, I mentioned fibers made from polymers, he mentioned fibers of DNA/RNA almost 10' long in one bacterium. That'll tangle a cloud together for ya. Also lightening! I am thrilled.
Update: This is the 2nd email I sent him:

Several different observations support the idea that clouds are being held together by bacteria and are a bit "sticky".  

The best information comes from comparing normal clouds with jet trails - which are effectively sterile clouds. Jet trails dissipate quickly in the same sky where clouds persist. More significantly, one observes an occasional jet trail intersecting with a cloud. The part of the trail outside the cloud continues to dissipate while the part inside the cloud does not. Hence there must be forces holding the cloud together that are protecting the enclosed jet trail from dissipation. Those forces cannot simply be "water-to-water" forces.

There are other less compelling reasons to think clouds are a bit sticky.(1) One observes a fast cloud overtake a slower one, tear off a piece of the slower cloud, and continue on its way. (2) The upwind side of a cloud tends to bunch together in a way that looks more like tissue paper than like disconnected and homogeneously dispersed water particles. It just looks like a fibrous mat being rolled up. Over and over one sees the visual appearance of a non-uniform, non-homogenous, fibrous, and sticky structure.

Bacteria do contain long fibres (DNA and RNA, as you suggested in our phone converstation) and they are capable of producing oils, polymers, and other products. It would make clouds sticky. Many types of bacteria live in biofilms.

I do not know how to test this more quantitatively. One might try to:
(a) Locate free-floating bi-products, also in the cloud
(b) Sample over a surface, over a very short time span, and then do an assay to study the physical distribution of the organisms, and bi-products within the cloud. It might be easier to do this with fog at ground level.

Also on the subject of bacterial bi-products, is inter-bacteria signalling important for rain formation? Certain bacterial group behaviors like disease and bioluminesce, require a given population density before being triggered. The question is: what signals, if any, do rain forming bacteria (pseudomonas) use or require for rain formation? Could one suppress or enhance ice formation with the right signals?

evolution of bird flight

If you ever see a turkey round a corner while running, you'll get some other ideas about the use of wings. Using wings as they run, turkey's can turn on a dime.

Clouds and Jet Trails

I have been trying to see if there is any observable evidence that clouds are held together by bacteria. I noticed that Jet trails dissipate in a way that clouds do not. 

Yesterday I saw something compelling: a jet trail intersected a cloud. As I watched, the part of the jet trail outside the cloud dissipated. But the jet trail inside the cloud did not dissipate- it remained visible long after the rest of the trail was gone. This supports the idea that there is some non-water related force holding the cloud together.
Update: Perhaps as significant, is that I see examples where the jet trail stays visible for a short distance outside the cloud. This suggests to me a coating of adhesive fibers that is not as visible because it is not as humid. If the evidence for humidity is the visible cloud then the invisible one has to have something else going for it.

Role of bacteria in cloud formation

How is a cloud different from "vapor" from a kettle? Clouds do not dissipate the same way. How much do you want to bet polymer- and oil-producing bacteria hold a cloud together?
Update:  How are clouds different from jet contrails?