Story ID: 
New Tool Helps Aviation Cut Climate Impact
By: Sarah Rose
Caption: Reducing contrails may outweigh small CO2 increases, according to researchers at UC Irvine
Word Count: 258
Researchers at the University of California Irvine have created a tool that could help the aviation industry reduce its climate impact by mitigating contrails. According to study published by university researchers, mitigating emissions such as contrails and nitrogen oxides may have greater long-term benefits, even if carbon dioxide output rises slightly as a result.
“We have always tried to build uncertainty quantification into our climate assessments,” said Michael Prather, professor of earth system science at UC Irvine. “But this new decision tool uses the information to provide accurate risk quantification for climate tradeoff decisions.”
Called Global Warming per Activity, the tool evaluates how different aircraft emissions affect the climate, including short-lived effects such as contrails and longer-term ones such as carbon dioxide. It allows users to create decision risk curves that weigh the probability of positive climate outcomes when making tradeoffs between emissions.
For example, rerouting a flight to avoid contrail-forming conditions may require more fuel, but the overall effect could reduce climate effects. The study found that a 3% to 5% reduction in contrails or nitrogen oxides could offset a 1% rise in carbon dioxide over 100 years.
The model addresses a longstanding challenge in climate science: comparing emissions that act on different timescales. While focused on aviation, the tool can also be applied to other sectors such as shipping or agriculture, where emissions interact in complex ways.
“This is a win for both science and society,” Prather said. “We can find a balance that leads to meaningful progress.”