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The Paris Agreement

A landmark deal to combat climate change

By Michael Le Page and Linda Geddes

What is the Paris Agreement?

Newscom/Alamy

The Paris Agreement is a landmark deal to limit the impact of climate change by reducing greenhouse gas emissions and intensifying global efforts to build a sustainable low carbon future. Without such drastic action, scientists warn of a climate crisis, one in which sea levels rise by more than 5 metres over the coming centuries, while droughts, floods and extreme heatwaves ravage many parts of the world.

When it was agreed at the United Nations Climate Change Conference, COP21, on 12 December 2015, after more than twenty years of UN negotiations, the pact achieved the first universal and legally-binding agreement on global climate change by all countries.

The accord’s long term goal is to stop global temperatures from rising 2 ⁰C above pre-industrial levels this century, and aims to limit the increase to 1.5 ⁰C – a more ambitious goal than was expected before the summit.

However, many scientists at the time pointed out that the agreement does not go nearly far enough to achieve these aims, and were countries to stick both to the spirit and letter of the agreement we could limit global warming to under 4 °C, perhaps even under 3 °C.

However, the agreement does however contain a “ratchet mechanism”. Countries must state every five years what they are doing to tackle climate change – what is known as their nationally determined contribution. Each successive NDC “will represent a progression beyond” the country’s previous one. The idea is that this will ensure countries rapidly “ratchet up” their ambitions.

The agreement also emphasises the need for global carbon emissions to peak as soon as possible and to undertake rapid reductions thereafter in accordance with the best available science.

It built on a previous UN treaty signed in 1997, The Kyoto Protocol, which also set emission reduction targets. This deal was widely regarded as ineffective because two of the world’s largest emitters of greenhouse gases – the United States and China – never ratified it.

On the other hand, the Paris agreement, which entered into force on 4 November 2016, has, as of January 2021, been ratified by the European Union and 189 states, including China, India and the United States, which are together responsible for more than 97% of global carbon emissions.

While the deal is legally binding, countries can withdraw from it without consequences, an option only the United States has so far taken up when in 2017 US President Donald Trump announced his intention to withdraw the country from the pact. This decision was immediately overturned in 2021 within hours of the inauguration of his successor, President Joe Biden.

Criticisms levied at the pact say that the gulf between what is being done and what is required is huge, and nothing in the deal compels countries to make much greater efforts required.

Others have stated that to achieve 1.5 °C would take nothing less than revolutionary changes across the world. “We need renewable energy, nuclear power, fracking, zero-carbon transport, energy efficiency, housing changes,” according to Piers Forster at the University of Leeds.