Study shows 40% increase in CO2 emissions from long-haul flights due to Russia-Ukraine war

The surge in emissions is largely due to the closure of airspace over conflict zones, forcing airlines to adopt longer, alternative routes that significantly extend flight times. Longer flights consume more fuel and increase operational costs for airlines, exacerbating their contribution to climate change.

The research highlights how conflicts can unexpectedly impact climate change. Understanding this dynamic is crucial for addressing the environmental impact of aviation.

The war in Ukraine has closed the country's airspace and restricted access to Russian and Belarusian airspace, marking the largest airspace closure since the Cold War, affecting 18 million km².

Airlines that previously used Russian or Ukrainian airspace for routes between Europe and Asia, North America and Asia, and North America and the Middle East now face significant detours. For example, Finnair's flight AY73 from Helsinki to Tokyo now covers an additional 3,131 kilometers, extending flight time by 3.5 hours. North American flights to Asia have been rerouted through the Arctic and Central Asia.

Safety concerns and geopolitical sanctions have led airlines to cautiously avoid restricted zones. 

The situation is further complicated by restrictions in other conflict regions, such as the Middle East, where airspaces over Syria, Yemen, and Iraq are also considered no-fly zones for many airlines. The global aviation map has been redrawn, forcing airlines to quickly adapt to a new and complex reality.

This has resulted in significant financial and environmental costs. An analysis of 14 long-haul routes between Europe and Asia, affected by airspace restrictions and operated by Finnair, LOT Polish, and Lufthansa, revealed that rerouted flights burn an additional 23 to 28.5 tons of fuel per trip, emitting an extra 72 to 90 metric tons of CO2. This is equivalent to the annual emissions of several cars per flight.

Airlines have also reported increased operational costs due to additional flight hours, including higher fuel costs, air navigation charges, and crew salaries. The analysis showed that costs on some Europe-Asia routes have risen by 19-39%, with emissions increasing by 18-40% depending on the airline.

LOT Polish Airlines reported a 23% increase in average aircraft operating costs on routes from Warsaw to Beijing, Tokyo, and Seoul due to flight restrictions, with CO2 emissions rising by 24% and ticket prices also increasing.

Finnair, which historically relied on Russian airspace for efficient Europe-Asia connections, has been particularly affected. Post-restrictions, aircraft operating costs on routes from Helsinki to Shanghai, Tokyo, and Seoul have risen by 39%, with average CO2 emissions on these routes increasing by 40%.

The study sheds light on the often-overlooked carbon footprint of war, which is rarely considered in climate policy. Using a forecasting model with specialized software, researchers found that continued avoidance of Russian and Ukrainian airspace could lead to a 29% global increase in aviation-related CO2 emissions by 2025 compared to 2022.

Aviation already accounts for 2.5% of global CO2 emissions, a figure expected to rise with the expansion of air travel.

These findings underscore that the need for transport decarbonization cannot be separated from broader geopolitical issues. As wars and conflicts alter airspace availability, they also worsen aviation's carbon footprint—a cost borne not just by the aviation industry but by all of us in the form of rising temperatures and climate change.

Despite the challenges, solutions exist.

Upgrading aircraft fleets with more efficient models like the Airbus A350 and Boeing 787 can reduce CO2 emissions by approximately 20-25% compared to older models, such as the Boeing 777-200ER or Airbus A330-200.

Optimizing flight trajectories using modern air traffic management systems can help aircraft choose the shortest and most efficient routes, reducing unnecessary detours.

International agreements on collective airspace management during conflicts can keep major flight corridors open, ensuring airlines do not resort to inefficient routes.

Investing in sustainable aviation fuel, which emits less than traditional jet fuel, is another partial solution, though supply issues and high costs remain challenges. In the absence of viable low-carbon alternatives for aircraft, reducing air travel should be a priority.