Contrails — those lines of wispy white clouds that follow some jets — may not be so harmless.
Airlines and scientists are coming to a consensus that the water vapor trails created by airplanes at high altitudes may play a big role in global warming. That’s because those contrails, short for condensation trails, create clouds that trap heat in the atmosphere at the critical altitude where airliners fly.
In fact, contrail clouds may be a more significant factor in global warming than carbon dioxide or other fuel emissions, according to a European Union study measuring more than a decade of airline flights. It’s part of an emerging field of study in climate science called “effective radiative forcing,” which measures the total warming effect instead of the older standard of totaling CO2 emissions.
