New tool allows airlines to measure and make decisions with lower climate impact

▲ The system was developed by researchers at the University of California, Irvine. Photo: Europa Press

Europa Press

La Jornada Newspaper, Thursday, July 3, 2025, p. 6

Madrid. A new study led by the University of California, Irvine, reveals that airlines can make smarter decisions to reduce aviation's impact on global warming.

The research, supported by NASA and the National Science Foundation (NSF), is published in Nature and offers hopeful insights for the future of air travel and climate action.

Civil aviation contributes to global warming through several factors: carbon dioxide (CO2) from fuel, nitrogen oxides (NOx) that affect ozone and methane levels, and the formation of persistent condensation trails. Each of these factors contributes to trapping heat in the atmosphere. Historically, efforts to reduce one of these climate factors have often increased the other, leading to difficult decisions for the aviation industry.

But now, researchers led by Michael Prather, a professor of Earth system science at the University of California, Irvine, have created a new decision-making tool that measures the total climate impact of each aviation activity, including uncertainties. Called Global Warming Activity (GWA), this metric measures the duration and intensity of each component's impact on the atmosphere, whether over hours or a century. The key lies in quantifying the uncertainties of all these elements, allowing users to formulate a decision risk curve that calculates the probability that a given trade-off will succeed in mitigating climate change.

We've always tried to integrate uncertainty quantification into our climate assessments , Prather explained in a statement. But this new decision tool uses that information to provide accurate risk quantification in climate trade-off decisions.

Condensation trails

The study concludes that if aviation decisions result in just a 3 to 5 percent reduction in contrails or NOx emissions, they can offset a 1 percent increase in CO2 emissions over a 100-year period. In other words, carefully selected strategies that slightly increase fuel consumption can reduce the long-term climate impact of flying. This approach has only been applied to damage caused by climate change and has not addressed trade-offs in terms of economic costs (such as higher fuel consumption per flight).

While previous models often struggled to compare the effects of short- and long-lived pollutants, the GWA allows for more accurate activity-based comparisons, helping the aviation industry find the least harmful options to reduce climate change.

The implications go beyond aviation. The GWA tool could also help assess the climate impact of other industries, such as shipping, agriculture, or manufacturing, where different types of emissions compete and interact, Prather concludes.