What is the Paris Agreement? Everything you need to know

This article was updated on 25 October 2022.

Ahead of COP27, the world's focus has turned firmly to global efforts to tackle climate change. One of the cornerstones of that effort is the Paris Agreement.

But what is it and who's signed up to the Agreement?

Climate change is one of the biggest challenges facing the world today. It is responsible for the increase in extreme weather events, as well as an unbroken series of hottest years on record. Indeed, environmental concerns and the threat posed by climate change have been a consistent feature of the World Economic Forum’s Global Risks Report.

World leaders spent two weeks in Paris during December 2015 hammering out the final wording of an agreement to keep global temperature increases well below 2°C – and if possible 1.5°C – compared with pre-industrial levels.

It was adopted by 196 Parties at COP21 and came into force on 4 November 2016.

This can only be achieved through a significant reduction in emissions of greenhouse gases. Known as COP21 (the 21st Conference of the Parties to the UN Framework Convention on Climate Change), it was one of the largest gatherings of world leaders ever seen.

Everyone who attended COP21 made emission-cutting pledges. These are known as “intended nationally determined contributions”, or INDCs for short.

China's target is to reach peak CO2 emissions by 2030 at the latest, and to lower the carbon intensity of its GDP by 60-65% from 2005 levels by the same date.

The EU plans to cut greenhouse gas emissions by 55% by 2030 compared with 1990 levels, while the US aims to cut greenhouse gas pollution by 50-52% by 2030 from 2005, and to reach net zero by 2050.

The Paris Agreement came into effect on 4 November 2016, after its minimum threshold was met – 55 countries representing at least 55% of global emissions.

For countries that join after this point, the Agreement comes into force 30 days after that country "deposits its instrument of ratification, acceptance, approval or accession with the Secretary-General".

The most recent scheduled gathering of the parties – COP26 – took place in Glasgow last year. One of the key outcomes of that meeting was the approval of Article 6, the Paris Agreement's guidelines for carbon markets. It allows countries to voluntarily cooperate with each other to achieve their emission reduction targets.

The next gathering, COP27, will take in the coming weeks in Egypt.

Once a party has joined the agreement, they cannot begin the process of withdrawal for three years, but there is no financial penalty for leaving.

The Paris Agreement signifies years of work in trying to combat climate change. In 1992, countries joined an international treaty, the United Nations Framework Convention on Climate Change. In 2005, the Kyoto Protocol became a legally binding treaty. It committed its parties to internationally binding emission reduction targets.