EASA study: ‘airplane contrails warm planet twice as much as CO2’
According to a recent study conducted by the European Union Aviation Safety Agency (EASA), ordered by the European Commission, airline contrails warm the planet twice as much as CO2.
A team of leading experts in the field from the EU, the UK, and Norway discovered that, apart from CO2, the jet engine emissions also contain nitrogen dioxides, soot particles, black carbon, oxidized sulfur species, and water vapor, responsible for two-thirds of aviation’s climate impact in 2018.
The net impact of all these chemical substances is that they contribute to global warming. However, individually, the respective non-CO2 emissions have different warming and cooling effects. The report shows that the overall global warming potential for aviation, with a time horizon of a hundred years, is 1,7 times that of CO2.
The study confirms that the combined non-CO2 climate impacts from aviation activities are as important as those of CO2 alone. The report examines additional policies to address aviation’s non-CO2 climate impacts, contributing to the EU’s climate objectives and the Paris Climate Agreement. Besides, CO2 and non-CO2 reducing measures would also contribute to local air quality.
The policy options suggested by the study focus on three categories: market/financial-related, fuel, and air traffic management. The first category consists of a levy on aircraft NOx emissions. This would spur manufacturers and airlines to reduce these emissions.
The fuel-related measures – the second category – are about reducing aromatics in fuel leading to cleaner burning and reduced non-volatile particle emissions, and the mandatory use of sustainable aviation fuels.
‘Tip of the iceberg’
Finally, the measures in the air traffic management category are avoiding ice-saturated areas and a climate charge. Flights should be optimized and redirected to avoid climate-sensitive regions. The scientists noted that rerouting less than 2% of Japan’s flights reduced the warming effects of contrails by nearly 60%.
“These findings confirm that CO2 emissions are only the tip of the iceberg when accounting for aviation’s climate impact,” concludes Jo Dardenne, aviation manager at Transport & Environment. “Contrails of aviation need to be urgently tackled to avert a climate crisis. Air traffic should not bounce back to pre-corona levels.”
Affordable and sustainable
According to T&E, “the EU cannot afford to wait another five to eight years to implement these measures,” as the report proposes. “Contrail avoidance should be prioritized. Pricing for non-CO2 emissions is necessary to incentivize airlines to use eco-friendly flight routes.”
Flying less (often) is an obvious solution to reduce emissions. In the Netherlands, the Dutch rail NS already offers train rides as an alternative for short-distance flights. The challenge is to find the right balance between affordability and sustainability.
“We have to use this pandemic as a reset for aviation,” newspaper De Morgen writes. “We may not allow pollution to reach pre-corona levels again. So, we have to review how and why we travel. Why booking a flight if we can organize a video-call?”