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Ban Ki-moon addresses the European Parliament on the Paris Agreement, Oct 4 2016
Credit: UN Photo/Rick Bajornas.
6 October 2016 15:20

Explainer: Paris Agreement on climate change to ‘enter into force’

Sophie Yeo


Sophie Yeo

06.10.2016 | 3:20pm
International policyExplainer: Paris Agreement on climate change to ‘enter into force’

The Paris Agreement will formally come into force next month, legally binding countries that have ratified the deal to act on the pledges made last year.

This includes a commitment by every country to prepare increasingly ambitious pledges to tackle greenhouse gas emissions every five years, known as Nationally Determined Contributions.

There were two thresholds that had to be crossed before the deal could come into force: at least 55 countries covering at least 55% of global emissions had to ratify the deal.

The first of these thresholds was passed on 21 September. As of today, 74 countries have ratified the deal. The EU’s fast-tracked ratification, which concluded on 4 October with the European Parliament’s vote in favour, has now pushed the deal over the second threshold.

The deal won’t come into force instantly. The Paris Agreement stipulates that this will happen 30 days after both the thresholds have been crossed. The UN says this will be on 4 November.

But it does mean that it will be in force before countries meet again for their first major UN climate meeting since Paris — and before the US elections on the 8 November.

Unexpected haste

By all accounts, countries have acted with remarkable haste in ratifying the Paris Agreement.

A raft of countries ratified the deal on 22 April, which was the first possible opportunity to do so. These mainly included small island states, whose emissions are negligible in the context of global emissions.

While these early-ratifying small countries helped to inch the agreement towards the first threshold, it was important to bring the big emitters on board to reach the second threshold.

On 3 September, the US and China jointly ratified the agreement. Together they were responsible for 38% of global emissions. This provided a big boost, but not quite enough to tip the total beyond 55%.

For a short time, there was a question mark over how the remainder would be made up, with doubts clouding the will or ability of the remaining big emitters to ratify.

India, responsible for 4% of emissions, had opposed the inclusion of a ratification deadline in the G20 communique in September. The EU, whose member states make up 12% of emissions, was widely considered to have too many bureaucratic mountains to scale to make speedy ratification a reality. Russia, responsible for 8% of emissions, has said it will not fast-track ratification to simply to catch up with other nations that have already ratified.

Russia kept to its word and has not yet ratified the agreement. But India ratified on 2 October and the EU managed to fast-track its ratification, allowing the emissions of the member states which had already ratified domestically — France, Hungary, Austria, Germany, Slovakia, Portugal and Malta — to be counted towards the 55% total.

One quirk of the Paris Agreement is that the percentages of global emissions assigned to each country are not based on the most up-to-date statistics available, but rather the most recent data that each country has provided to the UN.

In some cases, there is a significant disparity between what the country has reported and what percentage of emissions it is responsible for today.

According to the Global Carbon Project, China was responsible for 27% of global emissions in 2014, compared to the 20% that it submitted to the UN in 2005 and was counted for the purpose of its ratification. Similarly, the US was responsible for 15% of global emissions, rather than the 18% counted towards ratification.

Based on the latest data, these two countries combined are responsible for 42% of global emissions, which would have eased the burden of crossing the 55% threshold by 4% compared to the earlier shares that were actually counted.

What does this mean?

The entry into force of the Paris Agreement has a number of important implications.

It means that many of the provisions set out in December will now become legally binding on nations that have ratified. This includes drawing up plans to tackle climate change and providing financial and technical support to developing countries. They will also have to undertake appropriate adaptation actions. Carbon Brief has an interactive graphic setting out the full details of the final deal.

Countries cannot withdraw from the agreement for three years following its entry into force. If a country decides to exit after this time has expired, they need to wait another year before they can formally leave.

In light of the US elections, this is an important provision. Republican candidate Donald Trump has pledged to withdraw the US from the Paris Agreement if he becomes president.

Entry into force means that, even if he withdrew from the Agreement on his first day in office, the US wouldn’t actually leave for another four years. Unless Trump won a second term, there would be another president in office when this took effect.


The rapid entry into force also causes something of a logistical headache.

No one expected the Paris Agreement to come into force as early as it did. Until the penultimate draft of the Paris text, there were no options to allow the deal to come into force before 2020.

While the Paris Agreement set the direction for future climate action, its guiding rulebook still needs to be developed. In particular, a huge workload has been assigned to the “Ad Hoc Working Group on the Paris Agreement” (APA), which was set up to prepare the deal for entry into force.

The deadline for these tasks is the first meeting at which the Paris Agreement is in force, by which time the group is meant to have completed the rulebook. The APA started discussing these issues in May but, thanks to the deal’s unexpectedly speedy ratification, this work is still unfinished.

Once the Paris Agreement goes into force, discussions technically start taking place under the “Conference of the Parties serving as the meeting of the Parties to the Paris Agreement” (CMA). Thanks to the early entry into force, this will now take place for the first time in Marrakech in November, which is known as COP22.

The problem is that only countries that have ratified the agreement can take part in these discussions. This has left many countries concerned that they’ll be left out of important future discussions on the technical side of the Paris Agreement.

The French and Moroccan presidencies have released a document aiming to ease these worries.

One option, they say, is to immediately suspend the CMA and continue working on the rulebook in Marrakech as though the agreement hasn’t come into force — that is to say, with the inclusion of all countries, whether they have ratified or not. The World Resources Institute, a think-tank based in Washington DC, has detailed information about the options available and how they could work.

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