There is a new and ominous controversy concerning aircraft contrails and their supposed ill-effects.  People with little or no scientific understanding are whipping up a furore over - nothing.  This tends to leave all the real ills of the world unattended, and let's face it, those we know of already are too great and too many to be sufferable.  But how much worse it is when the (already!) deluded dream up new imaginary ills!  With too much on our plates already, we are forced to concern ourselves with additional spurious delusions which, if they were to be taken seriously, would diminish our capacity to adapt to change, and ultimately to survive the upcoming onslaught.

A typical passenger transport plane (medium haul) burns 7 tons of fuel and unloads 7 tons of ice and 4 tons of gaseous oxides (mostly carbon dioxide) into the tropopause, which is the boundary between the troposphere and the stratosphere.

The troposphere contains about 80% of the atmosphere and is the part of the atmosphere in which we live, and make weather observations. In this layer, average temperatures decrease with height. This is known as adiabatic cooling, i.e. a change in temperature caused by a decrease in pressure. Even so, it is still more prone to vertical mixing by convective and turbulent transfer, than other parts of the atmosphere. These vertical motions and the abundance of water vapour make it the home of all important weather phenomena.

The troposphere's thermal profile is largely the result of the heating of the Earth's surface by incoming solar radiation. Heat is then transferred up through the troposphere by a combination of convective and turbulent transfer. This is in direct contrast with the stratosphere, where warming is the result of the direct absorption of solar radiation.

The troposphere is around 16 km high at the equator, with the temperature at the tropopause around –80 °C. At the poles, the troposphere reaches a height of around 8 km, with the temperature of the tropopause around –40 °C in summer and –60 °C in winter.

http://www.metoffice.gov.uk/education/secondary/teachers/atmosphere.html

Annual passenger jet aircraft fuel consumption is estimated to be 300 million tons.

http://www.after-oil.co.uk/runways.htm

The weight of the atmosphere is 5.25 petatonnes.

http://www.merlyn.demon.co.uk/astron-2.htmMA

One can see that, as a proportion of the weight of the atmosphere, the burnt fuel comprises FIVE MILLIONTHS OF A PER CENT.  It would take TWO HUNDRED THOUSAND YEARS at today's rate of air travel, (and believe me THAT CANNOT happen - fossil fuel will be gone in twenty years!) to half-fill our atmosphere with contrail gases.

Now, the water, the gaseous oxides and sulphates MAY have an appreciable effect on Global Warming, but are as NOTHING when compared with the Earth's volcanoes.

There are 1,500 active volcanoes on land and maybe TEN THOUSAND active volcanoes under the sea.   Beneath are a few links:

http://content.scholastic.com/browse/article.jsp?id=4886
http://www.windows.ucar.edu/tour/link=/earth/interior/volcanism.html
http://green.nationalgeographic.com/environment/natural-disasters/volcano-profile.html?source=G2308

The term "active" means "constantly emitting steam, gases, magma, and ash".  It is hard to quantify the total emitted by the land volcanoes, but let us assume they average a million tons of each per year.  That will give us fifteen hundred million tons of steam, fifteen hundred million tons of gases, fifteen hundred million tons of magma, fifteen hundred million tons of ash.

To put that estimate into perspective, the largest known eruption, Tambora, put 200 million tons of sulphur dioxide ALONE into the atmosphere in a single event!

http://www.bbc.co.uk/dna/h2g2/A781715

Getting back to the point, it can be reasonably argued that contrails are at least FIFTEEN TIMES LESS IMPORTANT THAN VOLCANOES when it comes to having an effect on our atmosphere.  Our atmosphere and ocean are in fact MADE FROM VOLCANO EMISSIONS.  How on Earth did we/can we survive?  Those emissions have been/are being "air-conditioned" over four billion years BY LIFE.  We're under no risk as long as we don't kill our forests or sea plankton.  Now, THERE IS A REAL ISSUE!

So forget all this bullfish about contrails.  You can bet your boots that anyone who advocates this idea is an ignorant dupe.  And yes, I have at least one person in mind.......

Oh, and yes.  A mile of "chemtrails" comprises enough "chemicals" (water, carbon dioxide) to exactly fill a crate-full of soda-pop bottles.  They contain NO metallic particles which might end up willy-nilly slaughtering bees!  (It would be as well to pass the products through a charcoal filter to remove the SOX, NOX, and trace hydrocarbons - but then Bob's yer uncle!)

Soda-pop, anyone?  Thirsty work, this debunking!