Carbon neutral goal for aviation won’t neutralise its climate impact – it needs Market Based Measures too

A report from the Manchester Metropolitan University shows that the emissions from global aviation will continue to have a climate impact for years and decades after they are emitted. CO2 stays in the atmosphere for a long time, and continues its warming impact. For this reason, the proposal of the aviation industry to go for “carbon neutral growth” after 2020 will have the effect of increasing the climate impact of aviation.  “Carbon neutral growth” in the way the industry sees it, by use of reductions in CO2 emissions from technical, operational and biofuels measures, will not keep emissions and their climate impact low enough. For there to be real “carbon neutral growth”, so argue Transport & Environment in Brussels, and the Aviation Environment Federation in the UK, requires an effective market based measure MBM) as well. The MMU report concludes that to mitigate aviation’s climate warming impact in 2050 through carbon neutral growth in 2020 will require a basket of measures, including MBMs, (such as the EU ETS) to bridge the gap between what can be achieved by the industry and ICAO’s proposed measures, and what is actually needed.


Carbon neutral goal for aviation won’t neutralise its climate impact – Report

30.9.2013  (Transport & Environment)

 shows that the International Civil Aviation Organisation (ICAO) and industry goal of carbon neutral growth in 2020 will not, as the name might suggest, neutralise aviation’s climate impact.

ICAO is meeting this week in Montreal to attempt to conclude 16 years of negotiations on a set of measures to tackle climate-change emissions from international aviation.

Even if ICAO and industry were to be successful in stabilising aviation’s CO2 emissions at 2020 levels, which is an established goal, this would not correspond to a stabilisation of aviation’s climate warming impact.

The longevity of CO2 already emitted into the atmosphere means that the sector’s climate warming impact will continue to grow long beyond 2020 because CO2 emissions accumulate in the atmosphere faster than they can be removed.

The report by climate researchers at the Manchester Metropolitan University (MMU) shows that even constant, or ‘neutral’, annual aviation CO2 emissions from 2020 still result in an aviation ‘radiative forcing’ (warming effect) increase by a factor of 1.6 in 2050 over 2020 levels, and by a factor of 2.5 in 2100. Real and effective measures to achieve the carbon neutral growth at 2020 goal would, the study says, reduce aviation’s radiative forcing in 2050 by 21% over the business-as-usual scenario. Previous research by the MMU has shown that deploying the maximum feasible reductions from technical, operational and biofuels measures, favoured by ICAO and industry, would only reduce aviation’s climate warming (RF) impact in 2050 by 9%.

The report concludes that to mitigate aviation’s climate warming impact in 2050 through carbon neutral growth in 2020 will require a basket of measures, including market-based measures, to bridge the gap between what can be achieved by the industry and ICAO’s proposed measures, and what is actually needed.

Bill Hemmings, sustainable aviation manager at Transport & Environment, said: “ICAO’s head-in-the-sand approach, focusing on technology, operations and biofuels, falls far short of what is needed for our climate. This robust analysis is compelling and the science is clear: ICAO needs to consider the climate impacts of its CO2 mitigation goals when determining policy in Montreal.”

Analysis has already shown that continuing with the EU ETS will reduce the 2050 radiative forcing by 19.5%. Achieving a 21% result through carbon neutral growth in 2020 will require ICAO to agree to implement a market-based measure (MBM) which is as effective as the EU ETS in delivering real emissions reductions.

Combined with other measures, a global MBM starting in 2012, coupled with technology and alternative fuels, could reduce radiative forcing by around 30% by 2050, but ultimately stabilising the climate impact will require a more ambitious goal. The report did not consider aviation’s non-CO2 effects which will also contribute to a significant increase in radiative forcing nor whether offsets would bring real emissions reductions.

Tim Johnson, Director at the Aviation Environment Federation, said: “Even the modest goal of carbon neutral growth by 2020 will be impossible to achieve without a market-based measure as effective as the EU ETS, which Europe has been pressured to weaken. The international aviation community says it is serious about combatting the harm its industry does to the climate – now it must act to show these words are more than just hot air.


Click here for the full MMU report.




Climate impacts from aviation 2020 Carbon Neutral Goal: stabilized emissions but increasing radiative forcing and temperatures

Date added: September 27, 2013

A new, and rather technical, paper has been produced by CATE, the Centre for Aviation Transport and the Environment, at Manchester Metropolitan University. They have looked at the climate impacts of future scenarios of aviation emissions. The ICAO process that is attempting to deal with aviation emissions only deals with international aviation, ie between countries. Not domestic aviation, which is flying within a country, and of which there is a great deal in countries like the US and China. CATE has produced various scenarios which show that even if the global aviation industry managed to achieve its stated aim of “Carbon Neutral Growth” after 2020, for domestic and international flights, there would be a continuing increase in both radiative forcing (ie. the difference of radiant energy received by the earth and energy radiated back to space) and global temperatures from the aviation emissions. This is because although 30% of CO2 emissions are removed in a few decades, some 50% is not removed for several centuries, and about 20% remain for millennia. This is why under overall climate (temperature) stabilisation scenarios, global CO2 emissions must be reduced dramatically.

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Click here for the full MMU report.



A Market  Based Measure is defined by ICAO as:

Market-based measures include: emissions trading, emission related levies – charges and taxes, and emissions offsetting; all of which aim to contribute to the achievement of specific environmental goals, at a lower cost, and in a more flexible manner, than traditional command and control regulatory measures. Market-based measures are among the elements of a comprehensive mitigation strategy to address greenhouse gas (GHG) emissions from international aviation that are being considered by ICAO.


Wikipedia defines Market Based Environmental Policy Instruments as

In environmental law and policy, market-based instruments (MBIs) are policy instruments that use markets, price, and other economic variables to provide incentives for polluters to reduce or eliminate negative environmental externalities.


Examples include environmentally related taxes, charges and subsidies, emissions trading and other tradeable permit systems, deposit-refund systems, environmental labeling laws, licenses, and economic property rights. For instance, the European Union Emission Trading Scheme is an example of a market-based instrument to reduce greenhouse gas emissions.


Emissions trading
 or cap and trade is a market-based approach used to control pollution by providing economic incentives for achieving reductions in the emissions of pollutants.

A central authority (usually a governmental body) sets a limit or cap on the amount of a pollutant that may be emitted. The limit or cap is allocated or sold to firms in the form of emissions permits which represent the right to emit or discharge a specific volume of the specified pollutant. Firms are required to hold a number of permits (or allowances or carbon credits) equivalent to their emissions. The total number of permits cannot exceed the cap, limiting total emissions to that level. Firms that need to increase their volume of emissions must buy permits from those who require fewer permits.