Global CO2 Emission Trends from Air Travel: A Sharp Drop During the COVID-19 Pandemic

The International Energy Agency (IEA) report states that aviation contributes more than 2% of the world's CO2 emissions. This contribution has grown faster in recent decades than emissions from road vehicles, trains, or shipping.

Aircraft fuel, avtur, produces CO2 (carbon dioxide), an effective heat-trapping gas that contributes to global warming.

The attached data shows a significant decrease in emissions between 2008 and 2009. International flights contributed 454.44 million tonnes (mt) of CO2 emissions in 2008, decreasing to 433.24 mt in 2009. Similarly, domestic flights decreased from 298.14 mt to 279 mt.

Subsequently, emissions tended to increase, peaking in 2018-2019. International flights reached 609.42 mt in 2018 and 618.82 mt in 2019. Domestic flights reached 408.40 mt in 2018 and 417.01 mt of CO2 in 2019.

In 2020, the Covid-19 pandemic caused countries to restrict flights to curb transmission, resulting in a drastic reduction in emissions from both international and domestic flights.

International flights emitted 299.06 mt of CO2 in 2020, while domestic flights emitted 287.24 mt.

The IEA report states: "After increasing by an average of 2.3% per year from 1990 to 2019, the Covid-19 pandemic caused CO2 emissions to plummet, from over 1,000 mt CO2 in 2019 to 600 mt in 2020."

However, after the Sars-CoV-2 outbreak was controlled in several countries, aviation activity increased again. The IEA estimates that CO2 emissions in 2021 reached approximately 720 mt for both international and domestic flights, roughly one-third of the 2019 emissions.

The IEA explains that many measures are being taken to reduce emissions to achieve the Net Zero Emissions by 2050 scenario.

The IEA report continues: "Short-to-medium-term priorities include promoting efficiency through fiscal and regulatory measures; stimulating investment in sustainable fuels; and developing alternatives to jet kerosene, such as battery-powered and hydrogen-powered aircraft."