CO2 Setback as Emissions on UK-Japan Air Routes Surge by 21%

Average CO2 emissions for flights between the UK and Japan have jumped by more than 21% since 2019. The data - at odds with industry sustainability initiatives - is due to aircraft flying longer and more complex routes.

Following Russia’s invasion of Ukraine in 2022, Moscow closed its airspace to most Western carriers, leading to increased journey times and fuel burn. This didn’t just affect flights to Russian destinations – it shut off a critically important air corridor linking Europe and the Far East.

Notably, CO2 emissions have increased despite airlines using more fuel-efficient planes. In summer 2019, an average of six nonstop flights a day departed from the UK for Japan. Three of these were older generation aircraft such as the Boeing 777-200ER. 

Of summer 2024’s five daily links, only two were flown by older models, with modern jets such as the Airbus A350 and Boeing 787 operating the other three. These new planes are typically 15-25% more fuel efficient than those they replace.

Crucially, total emissions from flights between the UK and Japan were higher in 2024 than in 2019 despite fewer flights being flown.

An 'Existential' Challenge for Airlines

The quest to make flying more sustainable is the single biggest challenge facing the industry. It’s a problem that Willie Walsh, head of airline trade body IATA, recently described as “monumental and existential.”

The figures for the UK to Japan route are just one example of complex geopolitics hindering progress towards more sustainable air travel.

The rising CO2 trend was not universal. There was better news on the busy transatlantic route between the UK and the United States. Emissions per flight between the two countries were down 7% in summer 2024, compared to pre-pandemic levels.

Total CO2 emissions also fell despite an overall increase in scheduled flights between the nations. The early retirement of fuel-thirsty planes such as the Boeing 747 is behind much of the improvement.

The emissions data is supplied by aviation analytics firm Cirium’s EmeraldSky platform. It accounts for the specific aircraft type and unique cabin specifications, combined with real-time operational information and flight conditions for maximum accuracy. 

Japan’s Enduring Appeal

Even with increased journey times - and CO2 emissions - from many key feeder markets, Japan remains a hugely popular destination for international visitors.

Just last week, Spanish flag carrier Iberia launched the longest route in its network. The Madrid to Tokyo service follows an ‘always east’ round-the-world path to avoid Russian airspace. The outbound flight from the Spanish capital takes 14 hours, with the return journey scheduled at 16 hours. 

New U.S. options are also in the pipeline, with ZIPAIR recently announcing a nonstop link from Tokyo to Houston. The Texan city already has double-daily flights to the Japanese capital.

A record 35 million foreign visitors are expected in Japan this year. Tourism spending projected to hit JPY 8 trillion ($51 billion). If realized, the figures will beat the 31.88 million visitors in 2019. The Japanese government has ambitious plans to attract 60 million visitors annually by the end of the decade.

However, the influx of international travelers has brought its own set of challenges, with ‘overtourism’ concerns at some of the country’s top attractions.

IATA Director-General Willie Walsh is among the confirmed speakers at the Skift Aviation Forum in Dallas, Texas on November 12. Click here to learn more about the event. 

Skift’s in-depth reporting on climate issues is made possible through the financial support of Intrepid Travel. This backing allows Skift to bring you high-quality journalism on one of the most important topics facing our planet today. Intrepid is not involved in any decisions made by Skift’s editorial team.