Thanks to Freedom's Phoenix editor Ed Vallejo, we have an excellent video of so-called “chemtrails” being created (and a wonderful shot of Ed's cute little grand son)!
What makes this video excellent is the description as well as the documentation of visible effects. From Ed's dialog we get a clear statement of facts and observations:
When: Dec 4, 2010
Where: Phoenix, AZ
Prior Sky Condition: Clear
Current Sky Condition: Hazy
Ed's observations are great, but he makes an errant statement when he says contrails would last for only “seven or eight jet lengths” and not stretch from horizon to horizon.
Under certain atmospheric conditions, there would be absolutely no expectation of contrail dissipation. Coincidentally, under those specific conditions, we would expect the sky to go from “clear” to the exact condition documented by the lens.
The specific condition under which we would absolutely expect this behavior is a super-saturated, super-cooled, stable air mass at the flight levels (25,000 – 40,000 feet pressure altitude) with near-constant wind speed and direction.
As a quick tutorial on reading the Skew-T, the bold red line is the air parcel temperature at the various pressure gradients. The bold blue line is the dew point. The left-hand scale is pressure in millibars, which is mapped to pressure altitude on the right-hand scale. The bottom scale is temperature in degrees Celsius, with the temperature grid represented by thin red lines sloping up and to the right at a 45 degree angle.
The thin blue lines curving up and to the left are the dry adiabats. Thin red lines curving up are the saturated adiabats. We would expect a “normal” air parcel to cool along the dry adiabat until reaching the constant mixing ratio (plotted along the grey lines from surface dew point) and then to cool along the saturated adiabat.
The chart on the right plots wind direction and speed at the various pressure gradients. Each long barb is 10 knots, each short barb is 5 knots, and a pennant is 50 knots. So, on the 1800 sounding, we can see the wind at 400mb was from the southwest (230 degrees) at 40 knots.
From the surface, the 1800 sounding shows initial instability of the parcel up to 800mb (6,700 ft), then a stable air mass all the way up to 200mb (40,000 ft). The parcel cools below freezing at 12,500 ft (just above 650mb).
The most interesting part of the 1800 sounding, though, is from 400mb to 200mb (24,500 to 40,000 ft). There, the temperature and dew point lines converge; the parcel is 100% saturated with water vapor. If there were clouds on that day, they would have to be in this range.
However, Ed made the observation that the sky was clear prior to taking the video. That means, as the parcel rose it became super-saturated. The air temperature in that range went from -24 degrees to -60 degrees, meaning the parcel also became super-cooled. The wind goes from a near-constant 230 at 40 knots up to 35,000 ft, then jumps to 65 knots and 77 knots at 40,000 ft, still from 230 degrees.
In other words, the 1800 sounding shows a super-saturated, super-cooled, stable air mass at the flight levels with near-constant wind speed and direction, exactly the conditions we would expect from Ed's description.
We can see from these plots very little change in the air mass over Phoenix for this six-hour window.
A jet flying over Phoenix on 4 Dec, 2010 would be expected to disturb the super-cooled air and form ice crystals in its wake (just like opening that beer from the very back wall of the fridge). Given the air temperature, we would expect the ice crystals to sublimate back into water vapor, but, since the air mass is super-saturated, there's no place for them to sublimate to on this particular day.
Given the constant wind speed and direction, the contrails left by the jets would move to the northeast at 2/3 to 1 nautical mile per minute. The contrail from a jet in three-minute trail of another, then, would be offset by two to three miles, depending on their altitude. This creates the observed grid effect, as Phoenix's proximity to the border makes it the flyover waypoint for Dallas and Albuquerque flights to and from Southern California.
Lastly, it is in the nature of solids suspended in fluid (like ice crystals in air) to move from areas of higher concentration to areas of lower concentration. So, in addition to being pushed to the northeast by the wind, we would expect the contrails to spread out and disperse, causing the hazy effect that Ed observed.
Now, if these planes were spraying some chemical or chemicals, we would also expect that spray to follow the same behavior, at least until the nozzles became clogged with ice. However, it is not an either/or proposition. Given the atmospheric conditions on that day, the things Ed observed absolutely will happen, so any spraying behavior would be in addition to the result of disturbing a super-cooled, super-saturated fluid.
So, the observations in Ed's video are insufficient to support the hypothesis that something was being sprayed that day. There are free tools available to proponents of that hypothesis that could either prove or disprove it, but, to my knowledge, none of them have actually used them; proponents rely instead on unscientific speculation.
With one two and a half minute video, Ed does more to get to the truth than any purported “documentary” on the subject, all of which suspiciously omit any mention of date, time, or place. Here's hoping more chemtrail theorists become as conscientious with their documentation as Ed!