Big data reveals the real climate impact of air travel around the world

For the first time, researchers have harnessed the power of big data to calculate greenhouse gas emissions by country from aviation for 197 countries covered by an international climate change treaty.

When countries signed the 1992 United Nations Framework Convention on Climate Change treaty, high-income countries were required to report their aviation-related emissions. But 151 middle- and low-income countries, including China and India, were not required to report such emissions, although they could do so voluntarily.

This is important because the United Nations Framework Convention on Climate Change relies on countries’ emissions reports during negotiations on country-specific emissions cuts.

“Our work fills the information gap, so this can inform policy and hopefully improve future negotiations,” says Jan Klenner, Ph.D. candidate in NTNU’s Industrial Ecology Program and first author of the new paper, which was recently published in Environmental research papers.

The new data shows that countries like China, for example, which did not report its aviation-related emissions in 2019, came in second only to the United States in terms of total aviation-related emissions.

“We now have a much clearer picture of aviation emissions by country, including previously unreported emissions, which tells you something about how we can reduce them,” said Helene Muri, a research professor at the Industrial Ecology from the Norwegian University of Science and Technology. Program Muri was one of Klenner’s supervisors and a co-author of the paper.

Big surprises, or not

As expected, the United States tops the list of emitters in terms of the total sum of aviation emissions for both international and domestic flights.

“When we looked at how per capita emissions are distributed, we could see that economic well-being leads to more aviation activity,” Klenner said.

That analysis also showed that wealthy Norway, with just 5.5 million people, ranked third overall, just behind the United States and Australia, when per capita domestic emissions were calculated.

Klenner tested the model he developed for this analysis using data from Norway. He published a paper reporting these results in 2022.

You might think that the geography of Norway, a long, narrow country with many mountains and a sparsely populated northern area, would be to blame for the numbers. But Klenner’s 2022 analysis showed that 50% of Norway’s domestic flights were between the country’s main cities, Oslo, Trondheim, Stavanger, Bergen and Tromsø.

“Emissions per person in Norway were incredibly high,” said Muri, who also co-authored the paper. “With this data set, we can confirm that from a Norwegian perspective, we have a lot of work to do because we are third in the world in terms of emissions per person of domestic emissions.”

A role for big data

Anders Hammer Strømman, a professor in NTNU’s Industrial Ecology Program and Klenner’s co-supervisor, said an important aspect of the study is that it shows how big data can be used to help regulate climate emissions. Strømman is also a co-author of the new paper.

“I think it illustrates very well the potential of this kind of work, where before we’ve relied on statistical offices and reporting loops that can take a year or more to get this kind of information,” he said. to say. “This model allows us to do instantaneous emissions modeling – we can calculate global aviation emissions as they happen.”

The model, called AviTeam, is the first to provide information for the 45 least developed countries that have never inventoried their aviation greenhouse gas emissions. Strømman says the model provides these countries with information that might otherwise be difficult or impossible to collect.

The ability to calculate aviation emissions in near real time could also provide an important tool as the industry makes changes to decarbonize.

“In the transition where we are talking about the introduction of new fuels and new technologies, this kind of big data allows us to identify those types of corridors or operations where it makes sense to test these strategies first,” said Strømman.