Current:Home > reviewsClimate Scientists Take Their Closest Look Yet at the Warming Impact of Aviation Emissions -MoneyMatrix
Climate Scientists Take Their Closest Look Yet at the Warming Impact of Aviation Emissions
View
Date:2025-04-17 04:02:04
An international team of prominent scientists has published what they say is the most comprehensive study to date calculating the complex climate impact of aviation emissions, reaffirming that contrail clouds produce more warming than carbon dioxide.
This kind of comprehensive analysis has only been performed a handful of times, starting with a report from the Intergovernmental Panel on Climate Change (IPCC) in 1999. The new study, looking at data from 2000 to 2018, notes that while the understanding of the impacts of aviation emissions “remains incomplete,” a series of new calculations considered “factors not previously applied in a common framework.”
“We wanted to produce a very high-quality benchmark assessment,” said David Lee, a climate scientist at Manchester Metropolitan University, who led the study and was also part of the IPCC assessment.
The study, which had been in the works since 2015, looked at both carbon dioxide and several types of “non-CO2” emissions in aviation. Carbon dioxide emissions are fairly well understood at this point, Lee said, but the impacts of non-CO2 emissions, which the study found account for about two-thirds of the net warming effect, are considerably harder to calculate.
The primary non-CO2 impact results from the emission of nitrogen oxides, water vapor and soot that can create heat-trapping contrail clouds. They form as emissions of hot gases and soot from aircraft engines activate water particles that freeze, producing the contrails, those straight, wispy white markings of a plane’s path through the sky.
Other non-CO2 emissions involve what the study calls “aviation aerosols”—small particles composed of black and organic carbon known as soot, sulfur and nitrogen compounds.
The team measured the “radiative forcing” of each item—a measure of how much potential it has to exert a change on the global climate.
Over the last decade the science around these emissions has improved drastically, Lee said, but he added that the better science doesn’t always mean the uncertainties will narrow. “We find out other stuff that we didn’t know before,” he said.
The climate impact of contrails has been a topic of contention in recent years. Contrails form in certain atmospheric conditions when the water vapors from airplane engines condense and freeze in the air—or when soot particles allow water in the atmosphere to condense around them—creating artificial clouds. The trails can become cirrus, or curling, clouds and hang around for hours, trapping atmospheric heat which contributes to global warming.
Of all the emissions measured, the researchers found these contrails to be the most impactful, but there’s a caveat.
“Contrail cirrus forcing is not as powerful as we used to think it was,” Lee said. The contrails appeared to be less than half as effective as previous estimates found. Carbon dioxide emissions, meanwhile, were the second most impactful, with roughly 60 percent as much effect on the climate as the vapor trails.
Measuring the effects of nitrogen oxides was tricky because they both eliminate atmospheric methane, which has a cooling effect, but create ozone which can act as a greenhouse gas. Between these two mechanisms, the researchers estimate that nitrogen oxides have a net warming effect that is about 30 percent as powerful as the vapor trails. The other emissions didn’t appear to have strong effects.
Even though contrails showed less effect than previous estimates, their impact is still considerable, given that warming from the contrails is greater than from carbon dioxide—and that the carbon dioxide emissions alone from the airline industry equal 2.4 percent of global CO2 emissions, according to a 2019 study by the International Council on Clean Transportation.
The magnitude of these emissions is also growing quickly. The International Civil Aviation Organization estimated pre-Covid-19 pandemic that demand for air travel would grow 4.3 percent annually for the next two decades.
“The airlines did not dispute that there was an impact of CO2 on the atmosphere,” said Annie Petsonk, the international counsel at the Environmental Defense Fund, who was not involved in the study. But until now, she said, they have claimed the science isn’t in on non-CO2 airline emissions.
This paper, in filling that knowledge gap, deprives airlines of excuses to avoid dealing with non-CO2 emissions, said Petsonk. While the European Union has voluntarily adopted stricter standards for aviation emissions, the United Nations body that governs international aviation standards recently adjusted an international agreement after airlines asked for reprieve, citing lost revenue because of Covid-19.
“The airlines are in the midst of a Covid crisis, which has hit them with a gut punch and they’re trying to get back on their feet. If they fail to put the climate crisis central to their rebuilding, then their efforts… will fail,” Petsonk said.
She said that getting aviation “on a trajectory for net zero climate” needs to be at the core of the industry’s recovery efforts from Covid-19 setbacks.
veryGood! (6)
Related
- 'As foretold in the prophecy': Elon Musk and internet react as Tesla stock hits $420 all
- Search for Maui wildfire victims continues as death toll rises to 114
- Fire tears through historic Block Island hotel off coast of Rhode Island
- Lionel Messi, Inter Miami face Nashville SC in Leagues Cup final: How to stream
- Don't let hackers fool you with a 'scam
- Tropical Storm Emily takes shape in the Atlantic, as storm activity starts to warm up
- John Stamos Shares Adorable Video With 5-Year-Old Son Billy on His 60th Birthday
- Watch: Harry Kane has assist, goal for Bayern Munich in Bundesliga debut
- Backstage at New York's Jingle Ball with Jimmy Fallon, 'Queer Eye' and Meghan Trainor
- Regional delegation meets Niger junta leader, deposed president in effort to resolve crisis
Ranking
- What to watch: O Jolie night
- Drug dealer sentenced to 10 years in prison in overdose death of actor Michael K. Williams
- Ukraine making progress in counteroffensive, U.S. officials say
- WWE star Edge addresses questions about retirement after SmackDown win in hometown
- Warm inflation data keep S&P 500, Dow, Nasdaq under wraps before Fed meeting next week
- Spoilers! 'Blue Beetle' post-credit scene makes a big reveal about future of DC universe
- Ohio State wrestler Sammy Sasso shot near campus, recovering in hospital
- US, Japan and Australia plan joint navy drills in disputed South China Sea, Philippine officials say
Recommendation
Tom Holland's New Venture Revealed
Patriots-Packers preseason game suspended after rookie Isaiah Bolden gets carted off
Look Hot and Stay Cool With Summer Essentials Picked by Real Housewives of Atlanta's Kandi Burruss
1 dead, 185 structures destroyed in eastern Washington wildfire
North Carolina trustees approve Bill Belichick’s deal ahead of introductory news conference
FEMA pledges nearly $5.6 million in aid to Maui survivors; agency promises more relief
Microsoft pulls computer-generated article that recommended tourists visit the Ottawa Food Bank
Tanker believed to hold sanctioned Iran oil begins to be offloaded near Texas despite Tehran threats