Unraveling the Mystery of Contrails: How They Impact Climate Change and What Airlines Are Doing About It
As millions of Americans gear up to travel home for the holidays, a new concern has emerged regarding the environmental impact of their flights. While carbon emissions from planes have long been a focus of climate discussions, a recent report from the U.N. Intergovernmental Panel on Climate Change (IPCC) has shed light on another significant contributor to global warming: contrails.
Contrails, the thin, wispy clouds that form behind jet engines in cold, damp air high in the atmosphere, have been identified as a major factor in the airline industry’s warming impact. In fact, the IPCC report suggests that contrails may have a more significant effect on global warming than the burning of jet fuel itself.
In response to this finding, airlines such as American, Delta, and KLM are exploring ways to mitigate the impact of contrails on the environment. One potential solution being considered is rerouting planes to fly slightly lower or higher to avoid creating contrails altogether.
According to Marc Shapiro, who leads the contrails team at Breakthrough Energy, a climate organization backed by Bill Gates, avoiding contrails could be one of the most cost-effective climate solutions available to the aviation industry. By steering clear of contrail-prone regions, airlines could significantly reduce their warming impact in the short term.
While contrail avoidance presents a promising opportunity to address aviation’s climate impact, there are still challenges to overcome. Computer models struggle to accurately predict which contrails will contribute to warming, and airlines must weigh the cost of rerouting flights against the environmental benefits.
Despite these uncertainties, the European Union has taken steps to address contrails’ impact on climate change by requiring airlines to monitor and report their non-CO2 climate effects, including contrail warming. This regulatory pressure has prompted airlines to take action and explore innovative solutions to reduce their environmental footprint.
Researchers at Google and MIT have developed AI models to detect contrails in satellite images, enabling airlines to reroute flights away from contrail-prone areas. Early tests have shown promising results, with rerouted flights producing significantly less contrail cover while burning only slightly more fuel.
As the aviation industry continues to grapple with the complex challenge of reducing its environmental impact, the focus remains on finding a balance between avoiding contrails and reducing carbon emissions. While contrail avoidance may offer a short-term solution, long-term efforts to transition to sustainable fuels and eco-friendly aircraft will be essential in addressing aviation’s contribution to global warming.
In the words of Andrew Chen, principal for aviation decarbonization at the Rocky Mountain Institute, “We can’t just avoid contrails at the expense of taking carbon out of flying. This is something the sector has to address in addition to its existing work on carbon.”