• Seven-year study finds most airlines greenhouse gas emission are growing
  • Finnair has the smallest carbon footprint out of 20 major airlines
  • US carriers American Airlines, US Airways and Delta biggest polluters
  • Call for more transparency from airlines to study greenhouse gas emissions

Finland’s Finnair and TAP Portugal have emerged as the two least polluting carriers in a study of 20 of the world’s biggest airlines.

A study of the greenhouse gas emissions produced by the airline industry from 2007 to 2014 revealed none are showing a significant reduction over the seven years for those that provided the data.

In the study Finnair had the smallest carbon footprint in 2014, with TAP Portugal and Virgin Australia in the top three least polluting airlines, while American Airlines, following its merger with US Airways in 2013, had the largest footprint in the study with fellow US carriers Delta and United Airlines also large polluters in this sample.

Frederik Dahlmann, of Warwick Business School who conducted the study, said: “Finnair perform best due to the age and type of its planes, the routes it flies and the overall number of connections it offers. Plus it is probably among the most advanced when it comes to accounting for and managing its emissions over time.

Airlines pollution

“The data demonstrates that for most airlines emissions are either growing or stagnant, none are showing a significant reduction in CO2 emissions.

“This is despite many airlines introducing modern and more efficient planes to their fleet. The increasing number of flights, which is set to double by 2030, means cutting emissions is a real problem.

“Releasing details about carbon footprints is entirely voluntary, there is no obligation for airlines to disclose this data, so we have only been able to collect data for 20 major airlines. There are more than 200 international airline companies, but many would not provide the data.

“Some, such as EasyJet, Etihad and Ryanair, have only just begun to make their data publicly available. This explains why there is only data for 2014 for Etihad and Ryanair.

“We need more airlines to publicly account for their emissions so passengers can take emissions into consideration when arranging their travel plans.

“Even though it is not every airline the data still represents a huge challenge to the industry to meet its CO2 targets, which have come under criticism from environmental groups for not going far enough as the UN seeks to slow global warming to below 2C.

“It shows how much needs to be done to meet the new targets set by the industry bodies.”

Dr Dahlmann says the aviation industry produces around two per cent of the world’s human induced CO2 emissions, a figure predicted to grow to about three per cent in 2050 if no action is taken.

Last December’s UN Climate Conference of Parties (COP) in Paris led to an international agreement among nearly 190 countries to attempt to limit the increase in global temperatures to less than 2C and to continue efforts to limit it to 1.5C.

As a result the International Civil Aviation Organization (ICAO) has set itself the goal of reducing aviation’s net CO2 emissions to 50 per cent of what they were in 2005 by 2050. It also recently agreed the first-ever binding agreement for a four per cent cut in CO2 emissions compared to 2015 levels to all new commercial jets delivered after 2028.

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Some of the airlines that have seen a spike in carbon emissions can be explained as a result of recent merger activities, particularly in the US: for example American Airlines and US Airlines, United Airlines and Continental Airlines and in Europe British Airways and Iberia, now IAG.

Dr Dahlmann, who teaches Sustainability and Business Ethics on the full-time MBA, added: “The data illustrates the significant growth in recent years of certain younger airlines, such as Emirates. It may also reflect those airlines using older and more inefficient planes.

“Unfortunately the data does not provide a full and completely fair picture as not all companies disclose their emissions data and given the significant variations in business models, flight destinations and aircraft used.”

The aviation industry plays a vital role in the global economy and the ICAO is working with airlines and the wider industry to cut emissions through more efficient operations and a better use of infrastructure; the development of sustainable alternative aviation fuels; and research into more efficient design by aircraft and engine manufacturers.

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Dr Dahlmann examined data taken from 20 of the world’s biggest airlines’ annual reports and the Carbon Disclosure Project – a global voluntary carbon data reporting organisation – to explore the challenges the sector is facing. He included scope one and two emissions, that is direct and indirect CO2 pollution.

“It is important for the entire industry to manage the transition to a low-carbon economy through a systemic approach that covers all of their operations and the need for developing cross-industry partnerships, even with competitors,” said Dr Dahlmann.

“Given the role and importance of air travel we need to see as many activities as possible succeed to reduce the impact on the global climate and before we can experience truly ‘green flights’.”