White wispy trails across the blue sky on a sunny day are one of the few attractive features of air travel.
White wispy trails across the blue sky on a sunny day are one of the few attractive features of air travel. But they have a darker side, especially at night. For the condensation trails produced by the exhaust from aircraft engines are creating an often-invisible thermal blanket of cloud across the planet. Though lasting for only a short time, these “contrails” have a daily impact on atmospheric temperatures that is greater than that from the accumulated carbon emissions from all aircraft since the Wright Brothers first took to the skies more than a century ago.
More alarming still, researchers warned late last month that efforts by engineers to cut aircraft CO2 emissions by making their engines more fuel-efficient will create more, whiter, and longer-lasting contrails — notably in the tropics, where the biggest increases in flights are expected. In a paper being widely praised by other experts in the field, Lisa Bock and Ulrike Burkhardt of the Institute of Atmospheric Physics in Oberpfaffenhofen, Germany, forecast a near-tripling in the “radiative forcing” from contrails by 2050.
Aircraft emissions are rising up the climate agenda. With renewable energy taking over from fossil fuels in power generation, and the rise of electric cars, the continued surge in flights is increasingly seen as potentially the worst future threat to the climate, not least because there are as yet no carbon-free replacement technologies or international regulations to bring down emissions.
Read more at Yale Environment 360
