Plane contrails have been found to increase heat in the upper atmosphere. Credit: Nurphoto/Getty
The aviation industry has long been criticized for its large environmental footprint, particularly its climate-warming carbon emissions. But a new study suggests that another byproduct of airplanes—the white contrails they paint across the sky—has an even bigger warming effect, one that is set to triple by 2050.
Planes create their mesmerizinfg contrails as they soar high in the thin, cold air. Water vapor quickly condenses around soot from the plane’s exhaust and freezes to form cirrus clouds, which can last for minutes or hours. These high-flying clouds are too thin to reflect much sunlight, but ice crystals inside them can trap heat. Unlike low-level clouds that have a net cooling effect, these contrail-formed clouds warm the climate.
A 2011 study suggests that the net effect of these contrail clouds contributes more to atmospheric warming than all the carbon dioxide (CO2) produced by planes since the dawn of aviation. And those effects are predicted to get worse as air traffic—and the resulting cloud coverage—increases: […]
As far back as I recall reading about C02 levels and how the IPCC uses those for calculations, I do not remember ever seeing any stat where airplane emissions were used in the calculations. Neither was methane.