In praise of Britain’s Climate Change Act

Global carbon emissions, by country - climate legislation helps. Distantbody

Approved with overwhelming support from all political parties, the Climate Change Act came into force in 2008 and was hailed as a ground-breaking piece of legislation that would guide Britain’s transition to a low-carbon economy. Five years on, it is worth asking whether it has lived up to expectations.

There is no doubt that the act has consolidated Britain’s role as an international leader in climate policy. It is studied routinely when other countries embark on their own climate change legislation. Increasingly this includes not only industrialised countries, but also emerging markets like China, Mexico and South Korea. About 20 climate laws are passed each year.

Three features of the act stand out. The first is the statutory long-term target – an 80% cut in emissions by 2050, relative to 1990. The second is the establishment of five-year carbon budgets, also statutory, which determine the path to 2050. Four carbon budgets have so far been enacted, mandating an emissions cut of 50% by 2025, the mid-point of the fourth budget. The third feature is the establishment of an independent body, the Committee on Climate Change, which recommends and monitors the carbon budgets.

These provisions were put in place with a view to the long term. They recognise that without guidance politicians, with their eyes on the political cycle, would be unlikely to maintain a steady course toward a low-carbon future.

The full merits of the act are therefore only revealed in times of adversity. As long as there is consensus about climate policy, the act is barely constraining. It is at times of waning commitment that its provisions begin to bite.

Times like now, in other words, when we observe a growing adversity to climate policy in parts of the media and among some politicians. This is usually expressed as concern about rising energy bills, opposition to wind farms or enthusiasm for shale gas, rather than outright opposition to climate control. But there is no doubt that the Climate Change Act is facing its first major test.

So far its provisions have held. UK climate policy would be in a very different place without the act; we would almost certainly have a much more lenient carbon target for the 2020s, and the political discourse would have a different dynamic. A comparison with climate policy in the European Union, which lacks the guidance of a strong legislative basis, supports this conjecture.

Stiffer tests await: The fourth carbon budget, for the period 2023-27, is due for review in 2014. The fifth budget has to be agreed by 2016.

Some commentators see these constant challenges to the act as its main weakness. The act has not transformed political attitudes or the institutional balance of power on climate policy. Its achievements are still reversible, as can be seen in the situation in Australia.

The act itself recognises that in a field full of uncertainties it is worth checking from time to time whether its objectives are still appropriate. The evidence to date suggests they are. Much has been made of the recent pause in the rise of global temperatures. The pause is not fully understood and several factors are likely to play a role, including the possibility that the climate system may be slightly less sensitive than feared.

A helping hand from the climate system would be extremely welcome, but on its own is not a sufficient reason to change tack. Climate sensitivity is only one element in the causal chain that leads from greenhouse gas emissions to temperature change and from temperature change to impacts.

For most of the other elements in that chain the news has got worse. Greenhouse gas emissions continue to rise at the upper end of most predictions, and there is evidence that the socio-economic impacts of a given amount of warming may perhaps be more severe than previously thought, for example in terms of food security. Confidence in many of these findings is still low, but uncertainty reinforces, rather than weakens, the case for emissions control as a rational insurance policy.

What about the risk that the UK is moving too fast? Perhaps a slower pace of decarbonisation would be more appropriate. Models suggest otherwise, and the current emissions path is already back-loaded. The mandated carbon budgets require average emission cuts of about 3% a year until 2030, and about 5% a year thereafter.

To put these numbers into perspective; if capital investments have a lifetime of 20 years, one twentieth or 5% of the capital stock is renewed each year and can be replaced with cleaner alternatives as part of the normal investment cycle. Decarbonise faster and capital will have to be scrapped prematurely. It therefore makes sense to act early, even before we factor in technology reasons (learning effects may be stronger) and scientific reasons (emissions over the years will be lower) to do so.

In short, the scientific and economic rationale for the Climate Change Act has not changed. Five years after its inception, it remains a farsighted and innovative piece of legislation. The fact that its value is debated in some circles merely demonstrates how much it is needed.