By Paul Davies and Michael Green

Prior to the G20 Leaders’ Summit on 4 September, China and the US ratified the Paris Climate Agreement during a ceremony in Hangzhou, China. This commitment from the world’s largest carbon dioxide emitters is expected to prompt developed nations in Europe to follow suit.

The adoption of the Paris Agreement by 195 countries is widely considered to be one of the most ambitious international environmental agreements, whereby parties committed to limiting the increase in the global average temperature to 2˚C above pre-industrial levels while striving to limit the temperature increase to 1.5˚C.

China and the US join 25 other signatories who have ratified the Paris Agreement – the majority of whom are islands particularly vulnerable to climate change, for example, the Bahamas and Nauru. With China and the US now among the signatories, it is likely to accelerate the entry into force of the Paris Agreement.

Article 21(1) stipulates that the Paris Agreement “shall enter into force on the thirtieth day after the date on which at least 55 parties to the Convention accounting in total for at least an estimated 55% of the total greenhouse gas emissions have deposited their instruments of ratification, acceptance, approval or accession.” China and the US account for nearly 40% of global emissions and therefore the backing of these two nations is crucial to achieving the objectives of the Paris Agreement.

With the exception of Norway, China and the US have also preceded ratification by any European country, a development which is expected to exert pressure on developed countries, particularly those who usually take a strong position on environmental issues such as Germany and the UK.

The stage is now set for the ratification process to gain significant momentum – the coming months will be key.

Read more on the Paris Agreement and China’s environmental initiatives:

EU to Fast-Track 2030 Climate and Energy Policy Post-COP 21

China One of First Countries to Sign Paris Agreement

China to Promote Green Finance at G20

Green Bonds: Green Striping to Fuel China’s Green Economy?