The Other Side of ‘Chemtrails’


The article Stolen Skies: The Chemtrail Mystery (EIJ, Summer 2002), contained many inaccuracies which deserve correction. Beginning with the subtitle, “Jet Trails in the Sky Used to Disappear; Now they Linger” author William Thomas leads the reader to believe that the contrails produced by 6000 commercial airplane flights per day are actually military jets – spraying of various substances worldwide.

Nothing could be further from the truth. The chemtrails idea is a hoax and an urban legend supported by speculation, hearsay, and rumor, but no tangible evidence.

Ever since airplanes reached cold enough air (lower than minus 40°F), probably as early as the Spanish Civil War, contrails have been forming. They have been known to persist for many hours if enough ambient moisture is available to inhibit their dissipation. By WWII, contrails were a significant threat to the stealth of bomber squadrons. Alternate return routes were taken to avoid persistent contrail cloudiness left behind on the outbound flight.

Contrails form when hydrocarbon fuel is burned and combines with oxygen. Hydrogen from the fuel, plus oxygen, yields water, which freezes quickly into ice crystals. If temperatures are above minus 40°F, it is unlikely that a contrail will form. If cold enough, the ice crystals forming the contrail will behave just as any other cloud. If enough moisture is already present in the air, the contrail can spread by growth of the crystals, or be blown into normal-looking cirrus clouds. If the air is too dry, the contrail will eventually dissipate, either rapidly or up to several hours later.

Ironically, technical advances in engine efficiency have resulted in jet engines that burn fuel more completely, thus combining more hydrogen with oxygen and yielding more water for contrail formation. Better engines also have resulted in cooler exhaust temperatures, making it easier for the contrails to form. The prospect of a hydrogen-fueled jet which might be squeaky clean but leaves a massive contrail of water vapor would be sure to raise aesthetic questions.

Jet aircraft do leave behind unseen carbon dioxide and oxides of sulfur and nitrogen. These emissions have similar consequences to other fossil fuel use. Aviation produces a relatively small amount of these pollutants (13 percent) compared to other transportation and a fraction of the global emissions (2 percent). Modern jet engines are among the most efficient of all internal combustion engines.

The contrails formed do have a small effect on climate similar to natural cirrus clouds. Their high thin nature actually tends to warm the surface of the earth by reflecting heat back towards the surface. Contrail coverage of the earth currently amounts to 0.1 percent, and is projected to increase to 0.4 percent by 2050.

Active since 1997, the “chemtrails” hoax came to prominence during 1999 as millennium fears increased and originally focused on claims of poison chemicals designed to kill. Those dire predictions have not come to fruition. Later claims have focused on the idea that “chemtrails” are a form of amelioration of global warming. In fact, such geoengineering proposals have been made by prominent scientists, but assume that aerosols for blocking sunlight would be emitted high into the stratosphere, far higher than the contrails observed in the upper troposphere.

As a result of the promotion of the “chemtrails” hoax, much needless anxiety has been created. Some believers report immediate health effects upon sighting contrails six miles high, a physical impossibility. Profiteers have established a thriving cottage industry from the sale of books, tapes, and dubious medical products designed to “protect” people from supposed harm.

As it has over the past three years, time has a way of dealing with claims that fail to come true. The majority of people who initially believe in chemtrails eventually become aware of the factual and logical failings and abandon the idea. To a degree, this demonstrates that common sense wins most of the time. Let’s hope it always does.

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