Following the UK’s ratification of the Paris Agreement on 17 November 2016, the second instalment in our series sets out some of the technical detail on how the parties are expected to co-operate, and how this can be enforced.

How will the work be shared between signatories?

We read, in the last instalment, of the broad global goals on which the signatories have agreed to work together. However, to hold parties individually accountable, there needs to be a way to outline each signatory’s part of the bargain.

The Agreement contains a system whereby each party sets a ‘nationally determined contribution’ (NDC) to global emissions, which they then work to achieve. A party’s NDC must represent a progression from its current position, and will be reviewed at least every five years. What constitutes a ‘progression’ for each party will differ; for instance, developing countries may make progress towards their emissions peaking, whereas for developed nations a real-terms reduction in emissions is likely to be required.

Many countries have already submitted their proposals for what this contribution should be; their ‘intended nationally determined contribution’ (INDC), and an up to date list can be viewed on the Open Climate Network’s INDC tracker. When each party ratifies the agreement, their INDC crystallises as that party’s NDC. The UN tracks the NDCs here. They are not, however, set in stone as the Agreement allows them to be made more ambitious, but not less, at any time.

What is the incentive to set an ambitiously low NDC?

If all parties set their NDCs at the level currently intended, it is estimated that the resulting emissions would lead to a global temperature rise of more than 3°C above pre-industrial levels, thus missing the main target of the Agreement which is to cap this at 2°C. There is therefore a collective moral pressure among the signatories to play their part.

However, due to the cost of introducing new technologies to reduce emissions, and the possible strain any reduction could put on industry, infrastructure and development, there is also domestic pressure on each party not to take on the lion’s share of the responsibility whilst others escape. The parties are therefore engaged in the COP21 talks in Morocco to try and negotiate a solution in the face of these opposing obligations.

Is there any flexibility in how an NDC is achieved?

The Agreement recognises that a global reduction of emissions is more important than signatories sticking rigidly to their proposed methodologies. Thus, it does allow states to trade ‘internationally transferred mitigation outcomes’, in the interests of sustainable development which could otherwise be stifled by ambitious targets.

There are already similar mechanisms, such as those for carbon trading, in force under the Kyoto Protocol. However, a key difference in the Paris system is that the trade cannot simply offset emissions, it must deliver an ‘overall mitigation in global emissions’; that is, a net reduction. Furthermore, to avoid a situation where there is a great deal of conversation and very little action, only one party to each bargain can use the reduction resulting from the trade to demonstrate achievement of their NDC. Stand by for some interesting deals!

When will parties’ achievement of their NDCs be assessed?

There will periodically be a ‘global stocktake’, carried out at a conference of the parties to the Agreement, the first of which is scheduled for 2023. However, the parties are not free from scrutiny until then; as part of the duty of transparency imposed by the Agreement, they must regularly provide inventories of emissions, information on concrete progress towards their stated goals, the impact of any measures taken, and any contributions made by developed to developing countries.

What happens if parties renege on their commitments?

Article 15 of the Agreement establishes a formal committee of experts who will assess the information provided by each party and report to the conference of the parties. They are specifically required to act in a way which is ‘transparent, non-adversarial and non-punitive’. Therefore, although the overall limit on temperature increase and the reporting requirements are legally binding on the parties, there are no international or UN sanctions or penalties for non-compliance. UN Secretary-General Ban Ki-moon, when asked by a reporter from the Wall Street Journal whether the Agreement operated by a ‘shaming mechanism’, replied: “Yes. We are not going to shame, but everybody knows which country is doing what and how much they are doing. Everybody has an interest to fully comply.”

The bottom line, therefore, is that if a party decides not to comply it is prima facie able to do so. However, the hope is that the political repercussions a signatory would face from the international community, and the underlying threat of the devastating effects of climate change itself, will be enough to prevent this.

In the next and final instalment, we will look at the likely challenges the Agreement will face going forward; will this seemingly weak glue be enough to hold the accord together in the face of international tensions, and will the changing political landscape including Brexit impact on the position of the parties?