German and American researchers believe that ten percent of Central Europe is covered by clouds emitted from aircraft. The researchers are currently investigating whether emissions can be reduced if aircraft switch to biofuels, reports SVT.
The white lines behind airplanes, contrails, are condensed water vapor that has condensed into ice crystals. The ice crystals also contain soot particles, which some scientists believe is a major climate culprit.

Scientists from NASA and DLR, the German Aerospace Center, are using a specially built aircraft that flies up behind commercial aircraft and measures emissions in the condensation trail. So far, it has been shown that aircraft flying on a mixture of aviation kerosene and biofuel have reduced their emissions of soot particles by 50 to 70 percent, according to the German DLR.

Source: TT