DfT consultation on “Decarbonising Transport” – nothing of substance to cut aviation CO2

The DfT has quietly published (no press release or announcement – we are in the Covid-19 crisis) a consultation about Decarbonising Transport.  The end date is around June, but not specified.  Shapps says: “2020 will be the year we set out the policies and plans needed to tackle transport emissions. This document marks the start of this process. It gives a clear view of where we are today and the size of emissions reduction we need.”  And, less encouragingly: “We will lead the development of sustainable biofuels, hybrid and electric aircraft to lessen and remove the impact of aviation on the environment and by 2050…” (he actually believes electric planes will make much difference in a few decades??). It also says “Aviation, at present, is a relatively small contributor to domestic UK GHG emissions. Its proportional contribution is expected to increase significantly as other sectors decarbonise more quickly.” And while saying we are working with ICAO on its CORSIA carbon scheme (unlikely to be effective) the document states: “…we would be minded to include international aviation and shipping emissions in our carbon budgets if there is insufficient progress at an international level.” But overall the intention is to let demand for air travel continue to rise.



“Decarbonising Transport  – Setting the Challenge”



Published 26.3.2020  (no DfT press release – it just appeared ….)

Consultation till about June – no final date has been given (as we are in the Covid-19 crisis, with no certainty about when life might return to a semblance of normality).

Shapps says in the introduction (“Ministerial Foreward”)

… just some extracts of relevance to aviation below: 

“We will lead the development of sustainable biofuels, hybrid and electric aircraft to lessen
and remove the impact of aviation on the environment and by 2050, zero emission ships
will be commonplace globally.”

“As we move towards a net zero GHG emissions transport system, we cannot lose sight of the fact that the UK is on a journey with the rest of the world. Action is needed beyond the UK, and we are in a unique position to demonstrate real leadership domestically, as well as leading change in sectors that require global solutions, such as international shipping and aviation.”


This is the text in the section on Aviation:


Current position of the sector versus historical emissions

2.45 In 2018, UK domestic aviation (flights that take off and land in the UK) was responsible
for 1.5MtCO2e of GHG emissions  (53). This is a decrease of 6% since 2017, with domestic
aviation contributing less than 1% of UK GHG emissions and lower than the most recent
peak in 200554.

2.46 International aviation emissions, at 37MtCO2e in 201855, have more than doubled
since 1990. The majority of the increase came in the 1990s and early 2000s, however
emissions have also been increasing since 2012. There has been an increase of 1%
since 2017  (56  – see link ).

2.47 Aviation, at present, is a relatively small contributor to domestic UK GHG emissions.
Its proportional contribution is expected to increase significantly as other sectors
decarbonise more quickly.

Current government aims and targets

2.48 In December 2018, the Government published the Aviation 2050 green paper that
included a range of measures to achieve its 2050 ambitions at the time, including
efficiency improvements in technology, operations and air traffic management, use of
sustainable aviation fuels and market-based measures. The consultation closed in June
2019 and work is underway on the Aviation Strategy.

2.49 Airport expansion is a core part of boosting our global connectivity and levelling
up across the UK. The Government takes seriously its commitments on the
environment and the expansion of any airport must always be within the UK’s
environmental obligations.

2.50 Domestic aviation emissions are included in the UK’s carbon budgets with international
aviation and shipping emissions accounted for via “headroom” within our existing carbon
budgets, meaning that the UK can remain on the right trajectory for net zero global
greenhouse gas emissions across the whole economy. These international emissions
are treated differently, largely because the inherently international nature of both sectors
means that it is difficult to attribute these emissions to individual states. It is widely
agreed among states that a sectoral approach (rather than state-by-state) is preferable,
which is why the Kyoto Protocol gave UN International Civil Aviation Organisation (ICAO)
and the International Maritime Organisation (IMO) responsibility for pursing measures to
reduce these emissions.

Current policies in place to deliver those targets

2.51 Given their global nature and the absence of any international agreement on how to
assign international aviation emissions to individual states, action at an international
level is the Government’s preferred approach for addressing aviation’s international
carbon emissions.

2.52 The UK is already a respected and influential member of the UN International Civil
Aviation Organisation (ICAO). The UK has been instrumental in securing many important
environmental agreements including the 2016 Carbon Offsetting and Reduction Scheme
for International Aviation (CORSIA) agreement – the first worldwide scheme to address
CO2 emissions in any single sector – and the CO2 standard.

2.53 ICAO has defined a basket of measures designed to achieve its medium-term goal
of carbon neutral growth for the sector from 2020 (CNG2020). This consists of
more efficient aircraft technologies as incentivised by the CO2 standard, operational
improvements such as more efficient flight procedures, the development and use of
sustainable alternative fuels and market-based measures like CORSIA.

2.54 Under CORSIA, qualifying aeroplane operators are required to offset the growth in
international aviation CO2 emissions covered by the scheme above average 2019 and
2020 levels. At present, 82 states (including the UK) have volunteered to join CORSIA
from the start in 2021, representing over 75% of international aviation activity57. From
2027 to 2035, the scheme will become mandatory, meaning that over the entire lifecycle
of the scheme (2021 to 2035), it is estimated that approximately 2.5Gt of CO2 will be
offset58. Since 2012, the aviation sector has been part of the EU Emissions Trading
System (ETS). According to the European Commission, this has contributed to reducing
Europe’s carbon footprint by more than 17MtCO2e per year59. The UK committed in its
2017 Clean Growth Strategy that its future approach would be at least as ambitious as
the EU ETS and provide a smooth transition for relevant sectors

2.55 Figure 12 shows our central projection for GHG emissions from international and
domestic aviation to 2050. Between 2018 and 2050 demand is projected to increase
by 73%. However, emissions reductions per plane and per passenger km are driven by
larger and more efficient planes, and limited uptake of low carbon sustainable aviation
fuels. This results in aviation GHG emissions projections remaining broadly flat.

Figure 12: Projection of change in combined domestic and international aviation GHG emissions, passenger distance flown and gCO2/passenger km from current policy compared to 1990f60 Index (1990 = 100). GHG Passenger km GHG per passenger km

Planned future work

2.56 Later this year a consultation on net zero aviation will be published. This consultation
represents the growth in government ambition since the green paper, including the
2050 net zero target and further CCC advice on international aviation and shipping, and
will propose how the Government plan for aviation to play its part in delivering our net
zero ambitions.

2.57 Internationally, we are committed to negotiating in ICAO for a long-term emissions
reduction goal for international aviation that is consistent with the temperature goals
of the Paris Agreement, ideally by ICAO’s 41st Assembly in 2022. At the 40th ICAO
Assembly in October 2019, ICAO not only reaffirmed its commitment to CORSIA but
crucially, prioritised work towards a long-term climate goal for international aviation.


f Historic emissions are final UK GHG statistics 60. Historic passenger kms are DfT estimates based upon CAA airports data. Aviation forecasts are produced using the DfT Aviation model. The model is an updated version of the model used for the Aviation forecasts 2017. Key updates include revised fleet mix and aircraft efficiency assumptions. In addition, a precautionary approach to airport capacity assumptions was adopted such that these represent an upper bound for carbon emissions, but the approach does not pre-judge any future planning applications or the development of policy (including following the outcome of proceedings e.g. on Heathrow expansion).

2.58 As a responsible national government, we need a contingency measure in case
international progress does not go far enough or fast enough. That is why in the
Government’s response to the latest CCC Progress Report, we made it clear that we
would be minded to include international aviation and shipping emissions in our carbon
budgets if there is insufficient progress at an international level.


Britain hopes to:

• Lead international efforts in transport emissions reduction
• Recognise aviation and maritime are international by nature and require international solutions
• Harness the UK as a global centre of expertise, driving low carbon innovation and global leadership, boosting the UK economy


Within transport, road transport is the largest emitter of GHG. Cars contributed 55%
of domestic transport emissions (68MtCO2e) in 2018; as figure 3 shows, absolute
emissions from a number of transport sectors have decreased since 1990, but there
have been noticeable increases in emissions from vans and international aviation. (b)

(The image below just has the international aviation and shipping part of a large graphic)


b International aviation and shipping emissions are accounted for via “headroom” within our existing carbon budgets. This is consistent with the Kyoto Protocol which gives two UN Organisations – the ICAO and IMO – responsibility for pursing measures to reduce these emissions. There is no agreed way of allocating emissions to different countries, so our international emissions estimate are based on bunker fuels sales for international flights and journeys.


See the full consultation document at