Data Debate: Stop flying or become vegetarian? Part 1.

Hi, it’s Aya! I work in the support team at Datawrapper where I answer questions from our users. This week, together with Edurne (Eddie), also from our support team, we decided to do something new and fun: a Data Debate! Here is part one:

I was recently talking to Eddie about my new year’s resolution to be “kinder to the planet” and how we can aim to live a more sustainable lifestyle as a responsible adult. Step 1: Awareness. So we both went online and calculated our carbon footprints for 2019 using CoolClimate Network’s carbon footprint calculator.

Aya (me):




Then we compared our results. The CO2 equivalent – or CO2 eq – is a metric to show the global warming potential of other greenhouse gases by converting it to the equivalent amount of CO2 emission.

You see that two categories stand out here: Travel and Food. Compared to an average American, my carbon footprints exceeds in Food, while Eddie’s in Travel. (Keep in mind that these numbers are just estimates.

I eat everything. I especially love dairy products & meat, while Eddie is a vegetarian and doesn’t eat meat or dairy.


This is one of my favorite comfort foods: supposedly a “Japanese” dish with a western twist. We call it Hambagu, named after the city of Hamburg in Germany. It’s ground beef shaped into a ball and eaten with different kinds of sauce.

However, I haven’t traveled so much in the past year, while Eddie has traveled quite a lot. Eddie was working as a journalist in Kenya and was flying frequently to Europe to visit her families as well as traveling within the African continent. She also spent her summer in Asia.

So how bad is her flying for the environment, and why?

Air travel: a big part of Eddie’s total CO2 emissions

Eddie’s air travel emission (based on these rough estimates we got from the calculator) is 10.3 tons CO2eq more than mine. That’s almost 7 years worth of CO2 emitted from my meat & dairy consumption.

Most of the CO2 is produced by a few frequent fliers

Considering that, I was surprised to find that commercial aviation only accounted for 2.4% of total global CO2 emissions in 2018, while the food industry accounted for almost one-quarter of total global CO2 emissions. Out of these 2.4%, four-fifths comes from passenger operationsSo only around 2% of global CO2 emissions results from air travels.

That doesn’t seem like a lot. But according to Boeing, less than 20% of the world population has ever flown in their lives. What’s more, it’s the frequent fliers who are producing the majority of emissions:

In the US, only the 12 percent of Americans who make more than six round trips by air a year are responsible for two-thirds of all air travel. And Americans make up 24% of the global CO2 emission from air travels – that’s a big slice of pie. If one of these frequent fliers flies less, this person could make a big difference.

So if Eddie starts flying less, she would make a bigger difference on the climate than if I stop eating meat (because far more people eat meat regularly than fly as often as Eddie).

It’s not just CO2

We also have to consider the impact of aircraft engine exhaust in the atmosphere in high altitudes.

For example, if Eddie were to fly from her house in Madrid 🏠 to our office in Berlin 💼, here’s what CO2 emissions of different transport modes look like:

The problem with flying is that planes also generate things like nitrous oxide, water vapor, and soot. In high altitudes, these emissions other than CO2 amplifies the global warming effect caused by CO2 emission alone.

In high altitudes, emissions like water vapors, hydrocarbons, and soot particles emitted by planes cause ice crystals and condensation trails and cirrus clouds which can stay in the sky for hours, contributing to the warming effect.


Picture of a sky I took last winter. I always thought these vapor trails left by airplanes were pretty – until I learned how damaging they were to the planet.

What can Eddie do to reduce her travel footprint?

I understand that sometimes, it’s extremely inconvenient NOT to fly. Eddie had to travel to different countries for her work as a journalist and studies in the past years, which is why her emission is high. The next time I go home to Japan, I could take a train and a ferry and it would take me a few weeks, or I could take a 13-hour flight back to Tokyo. Do I have time for the train & ferry? Maybe not.

But it’s important is to be aware of the consequences of our actions. Rather than quickly booking a flight, consider other modes of transport and compare their carbon footprints. There are many ways to reduce your footprint while flying too, like choosing fuel-efficient carriers, flying economy, and more.

Next week, Eddie will try to convince me why I should go vegetarian. Let me know in the comments if I’ve missed something here or if you have any suggestions for further reading. Or you can reach us at See you next week!