Flights powered by air? Airlines are betting on it

By the middle of this century, most cars and buses should be powered by renewable energy while bikes, electric trains and your own two feet will continue to have little impact on the climate. And if global aviation achieves the goal it adopted last year, then a 2050 flight from New York to Hong Kong will result in “net-zero” carbon dioxide in the atmosphere. There is no guarantee that the industry will get there, but the technologies being developed in pursuit of the target will change aviation, regardless of whether the goal is met. In the years leading up to the pandemic, aviation emitted roughly a billion metric tonnes of carbon dioxide annually, about as much as the entire continent of South America in 2021. And the figures are bouncing back as passengers return to the skies. But major airlines, including six of the largest United States airlines, have pledged to achieve net-zero carbon emissions by 2050, if not sooner. At a meeting in October of the United Nations agency dedicated to civil aviation, delegates from 184 countries adopted net zero by 2050 as a “long-term global aspirational goal”. “Aspirational” is the operative word. Aviation is what experts refer to as a hard-to-abate sector, meaning there are not any easy, market-ready technologies currently that can drastically reduce its carbon emissions. And the “net” qualifier attached to the goal means that airlines can account for any carbon dioxide they continue to emit either by using traditional carbon offsets, a practice that has attracted major criticism, or by capturing carbon dioxide directly from the atmosphere. Scientists have also found that contrails – the wispy, short-lived clouds that sometimes appear in an airplane’s wake – affect the planet’s temperature, perhaps even more so than the carbon dioxide they release. It all adds up to a complex picture, especially given that global demand for aviation is expected to double over the next 20 years.<br/>