The debate about the impact of our movements is hot. Reducing the carbon footprint implies opting for other means of transport or reducing travel, for example. Credit: Wikimedia Commons.

  • Sustainability


Activist Greta Thunberg has decided to cross the Atlantic on a catamaran to attend the Madrid climate summit. We took advantage of her wake-up call on the pollution generated by airplanes to compare the data and analyse alternatives for travelling in a more sustainable way.


Greta Thunberg is now sailing across the Atlantic. The young environmental activist set sail for Europe on November 13th from the coast of Virginia (USA), aboard a catamaran. Her objective: to arrive in Madrid in time to attend the new UN conference on Climate Change (December 2-13). With this decision that goes against the tide, Thunberg wants to decry the excessive pollution caused by airplanes, and publicise the need to reduce that impact. More and more people are asking themselves the same question. How much damage to the environment do I cause by taking a flight? What possibilities exist to travel the same distance while leaving a smaller carbon footprint?

Thunberg herself admits that hers is a limited approach, and clarifies the reason behind her choice. "I decided to sail to highlight the fact that you cannot live sustainably in today’s society," she told The New York Times before leaving the U.S. for Spain with her father Svante and the two Australian Youtubers who offered them their own catamaran to undertake the journey.

This gesture serves to put into context the carbon footprint they are leaving compared to making the same journey in another mode of transport. Both the New York newspaper and the BBC point out that this boat uses mostly clean energy (such as solar and wind) and its footprint, since it moves mainly thanks to sails, is minimal compared to an airplane or a transatlantic cruise. The latter is an even more polluting option than a flight, according to data from the Swiss NGO Myclimate, which offers a tool for making this calculation.

Some companies are already limiting the frequency of flights on some routes to reduce the impact on the environment. Credit: Wikimedia Commons.

Data that speaks for itself

Beyond this particular case, the statistics make it clear that aircraft pollute much more than other means of transport. For every kilometre flown, a passenger generates 285 grams of CO2, while by car there are 104 grams, by bus 68 grams and by train 14 grams, according to the European Environment Agency. The International Civil Aviation Organization adds that the sector is responsible each year for 2% of CO2 emissions in comparison to total greenhouse gas emissions in the world, when transport in general is responsible for 14% of those emissions, according to the panel of UN experts.

And yet, planes seem to be taking off like never before: in 2018, more than 263 million passengers left or transited in Spanish airports alone, the highest figure since there have been records. In some countries the need to limit the environmental impact of such numbers, starting with short-haul flights, has begun to arise. For example, the Dutch company KLM has already decided to reduce daily connections between Amsterdam and Brussels from five to four by the end of March 2020, replacing one of them with fast train travel. "We invite all travellers to make responsible decisions about flying," said Pieter Elbers, president and CEO of the airline, in an open letter.

In Spain this issue is also beginning to find a place in public debate. Let's take as an example the Madrid-Barcelona route, which with more than 2,468,000 passengers a year in 2018 was the number one for both airports, with the most traffic in Spain. A return flight between the two cities can generate a carbon footprint of 230 kilograms, while a train would be 35, according to  Ecopassenger, the Internet tool provided by the International Railways Union. However, in the absence of a single standard, the figures may vary depending on the tools or applications used to make the calculation.


Concern about the carbon footprint left by transport leads companies to compensate with initiatives such as forest reforestation. Credit: Taking Roots

What to do when environmental-friendly alternatives are the most expensive?

However, in practice the greener alternative of taking the train is often limited by the time available or the price. While waiting for political decision-makers and the transport sector to take measures to guarantee options that are equally competitive and more environmentally-friendly than airplanes —and that don’t exceed the price of flights— we have another possibility when making our travel choices: consider the environmental commitments that airlines have made.

For example, IAG, the group to which British Airways, Iberia, Aer Lingus and LEVEL belong, recently announced its goal of achieving zero net CO2 emissions by 2050 with measures such as the use of more sustainable fuels, the offsetting of part of the emissions produced by flights with investments in verified carbon reduction projects and the replacement of old aircraft. Air France, for its part, has committed itself to offsetting 100% of the CO2 emissions produced by its domestic flights in France starting in 2020.

And if concern over the effects of climate change is still plaguing us, we can also look for other ways to offset at least part of the carbon footprint we leave on our travels, for example through projects offered by tourism agencies or NGOs

There is also an open debate on the need to reduce emissions within the UN itself. Close to 2000 employees of the international organization signed an open letter to the Secretary-General calling for the global body to reduce its carbon footprint, including limitations on business class flights and travel allowances. Two days later, the UN Secretariat announced a plan to reduce its emissions by 45% by 2030. The December climate summit will generate some 65,000 tons of CO2, which will be offset by the government of Spain.

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Tungsteno is a journalism laboratory to scan the essence of innovation. Devised by Materia Publicaciones Científicas for Sacyr’s blog.

  • Tungsteno
  • Travel
  • Carbon footprint
  • Planes
  • Greta Thunberg

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