Airplanes' contrails cause far more warming than their carbon emissions

By Michael Smith (Veshengro)

According to research by the DLR German Aerospace Center, airplane contrails have a much, much greater impact on global warming than do the carbon emissions caused by planes' engines. I can't emphasize the 'much, much' part of that enough.

ContrailsIn the Reuters summary it states: “Aircraft condensation trails criss-crossing the sky may be warming the the planet on a normal day more than the carbon dioxide by all planes since the Wright Brothers' first flight in 1903.”

In any given day the net warming effect of contrails and the cirrus clouds related to them was found to be 31 milliwatts per square meter. Warming caused by aviation over the past century-plus was 28 milliwatts per square meter. But while contrails dissipate quickly, those carbon emissions keep warming for decades and decades, an important consideration for dealing with the issue.

Why do contrails cause so much warming? In dense areas of contrails, found especially in parts of Europe and the eastern United States, the contrails themselves trap heat, as do the cirrus clouds related to them--so-called 'contrail cirrus' clouds, "a type of cloud that consists of young line-shaped contrails and the older irregularly shaped contrails that arise from them."

What ways are there to reduce contrails, besides the obvious of not flying, which I would advocate, are flying at lower altitudes, avoiding areas of the sky with high moisture content, developing new engines that reduce contrail formation. A balance, however, would have to be struck between these measures if doing so would result in burning more fuel.

The fuel burned by the aircraft engines themselves, unfortunately, also has a very high moisture content and also a very high soot level – it is noting but commercial kerosene – and thus, in itself, is a note very pretty fuel to use.

The best way to reduce those contrails and contributors to climate change is no flying or flying less. There are other ways of doing business – if that is why someone has to fly... video conferencing, etc., can do away with much of the need. If it is flying to a foreign field just for the summer vacation the answer would be to think about vacationing in the home country or even “at home” with the latter being my favorite choice each and every time. Very low emissions...

© 2011