Committee on Climate Change

In developing advice on the fourth carbon budget the Committee started by considering an appropriate and feasible target for UK emissions in 2030 – half way between now and the 2050 target in the Climate Change Act. This 2030 indicative target needs to reflect likely emissions in the early 2020s, feasible and cost-effective emissions reductions in the 2020s, and feasible pathways to further reductions between 2030 and 2050.
 
The fourth budget advice therefore joins up the detailed analysis that we have previously published on the path to 2020, with longer-term analysis of the path to 2050. Our advice is based on consideration of the latest climate science, the evolving international framework, feasible and cost-effective emissions reductions in the UK through the 2020s, and plausible paths to the 2050 target.

Our approach is demonstrated visually below (click on the image to enlarge the chart)

The key building blocks in the analysis are:

• We accept as a given the overall 2050 80% target, and the need to achieve still larger reductions in sectors other than international aviation and shipping  and in CO₂ (as against other GHGs).

We therefore define possible indicative targets for 2030, based on:

• The level of emissions with which we are likely to enter the 2020s, and/or could enter the 2020s with appropriate intensity of policy effort over the first three budget periods.
• The feasible and cost-effective pace of emissions reductions through the 2020s.
• The feasible pace of emissions reductions from 2030 to 2050.

The indicative targets for 2030, together with the pace of emissions reductions in the 2020s, then inform our recommendations for the fourth budget period.
 
In setting out our recommendations for the fourth budget, we have distinguished between the path which makes sense for UK domestic action, and the path that the UK should be willing to offer as part of a global deal:
 
The Domestic Action budget and indicative 2030 target

These reflect a bottom-up assessment of abatement opportunities during the 2020s , and include abatement measures which will either be cost-effective at projected carbon prices or which will be necessary to ensure a feasible path from 2030 to 2050. We recommended that the Domestic Action budget for 2023-2027 is legislated in the first instance, with the aim to meet it through domestic emissions reduction (i.e. without recourse to credits or allowances purchased in international carbon markets including the EU ETS).
 
The Domestic Action budget for 2023-2027 is 1950 MtCO₂e, which is a 50% reduction on 1990 levels in 2025, on the way to a 60% reduction on 1990 levels by 2030. Our fourth budget report considered how the budget could be met, and further opportunities for reductions to 2050.

In May 2011 the Government accepted our advice and proposed to Parliament that it should legislate a budget of 1950 MtCO₂e.

Global Offer budget and indicative 2030 target

These are intended to illustrate a possible UK contribution to the overall global emissions reductions required to achieve the climate objective . They are slightly more ambitious than the Domestic Action target and budget: the additional ambition could be achieved either via the purchase of emission reduction credits in international carbon markets, or via accelerated domestic abatement. The Global Offer budget is intended to be indicative of a minimum contribution to a global deal. It would only be legislated in the context of a global deal covering the 2020s, with a precise level of ambition to reflect the deal achieved.
 
The Global Offer budget for 2023-2027 is 1800 MtCO₂e, on the way to an indicative 2030 target of 63% below 1990 levels.
 

Click on the image to enlarge the chart
 
‘Back-ending’

The Domestic Action budget will only be a feasible stepping stone to the 2030 and 2050 targets if it is met on a gross basis (i.e. if the UK’s domestic emissions are at or below this level). We therefore recommended that, alongside legislating this budget, the Government commits to bring forward policy measures  which will make it attainable without the purchase of credits (additional reductions under the Global Offer budget could be delivered via credit purchase).

The Government has accepted that the aim should be to deliver the legislated 4th budget through domestic action (although the use of credits has not been ruled out).
 
It is important to recognise that the recommended budget requires steady acceleration of progress over time. Our proposed pace of progress through the 2020s is significantly faster than that required to meet carbon budgets in the 2010s, and faster still in the late 2020s and between 2030 and 2050 (see chart below), as reflected in total required emissions reductions of 46% between 2009 and 2030 and 62% between 2030-2050.
 
This is acceptable given the range of available technologies likely to be available through the 2020s and from 2030 to 2050. But the Committee judges any further ’back-ending’ of the reduction path (i.e. a less ambitious budget, requiring further acceleration towards the end of the 2020s) would risk making the indicative 2030 target unattainable, which would in turn put the 2050 target at risk.