In short
Nearly 200 countries agreed on December 12, 2015, to limit global warming to well below 2 degrees Celsius through the Paris Agreement, a legally binding international treaty negotiated over two weeks at the UN Climate Change Conference outside Paris. The deal marked the first time the world's largest emitters—including the US, China, and India—committed to emissions reductions under a single framework, replacing the 1997 Kyoto Protocol.
How it unfolded.
The five-minute version
What actually happened.
The Paris Agreement is an international treaty on climate change that was signed in 2016. The treaty covers climate change mitigation, adaptation, and finance. The Paris Agreement was negotiated by 196 parties at the 2015 United Nations Climate Change Conference near Paris, France. As of January 2026, 194 members of the United Nations Framework Convention on Climate Change (UNFCCC) are parties to the agreement. Of the three UNFCCC member states which have not ratified the agreement, the only major emitter is Iran. The United States, the second largest emitter, withdrew from the agreement in 2020, rejoined in 2021, and withdrew again in 2026.
As it was happening
13 voices, 8441 days.
One beat at a time. Click any dot on the timeline to jump, press play for autoplay, or use the arrow keys to step.
Kyoto Protocol adopted
First legally binding climate treaty created, but excluded major emitters and failed to achieve universal participation.
Voices from this moment (1)
Kyoto Protocol adopted
Dec 11
“First legally binding climate treaty created, but excluded…”
As it was happening
13 voices, 8441 days.
Day 0 · December 11, 1997
Kyoto Protocol adopted
First legally binding climate treaty created, but excluded major emitters and failed to achieve universal participation.
“First legally binding climate treaty created, but excluded…”
- Kyoto Protocol adopted, Dec 11
Day 4391 · December 19, 2009
Copenhagen Accord issued
COP15 produced a non-binding accord acknowledging 2°C target but without enforcement mechanisms or universal buy-in.
“COP15 produced a non-binding accord acknowledging 2°C…”
- Copenhagen Accord issued, Dec 19
Day 6563 · November 30, 2015
COP21 opens in Paris
Two-week UN Climate Change Conference begins with 196 parties represented, including record attendance from world leaders.
“Two-week UN Climate Change Conference begins with 196…”
- COP21 opens in Paris, Nov 30
Day 6575 · December 12, 2015
Paris Agreement adopted
All 196 parties unanimously adopt the Paris Agreement after marathon negotiations, establishing binding emissions reduction targets and climate finance mechanisms.
“Nearly Every Nation Endorses Landmark Climate Accord”
- The New York Times, Dec 13
“World Reaches Historic Climate Deal in Paris”
- BBC News, Dec 12
“The World Has Finally Agreed to Take Climate Change…”
- The Guardian, Dec 12
“Nations Reach Historic Climate Deal in Paris”
- Reuters, Dec 12
“L'accord historique de Paris sur le climat est une victoire…”
- Le Monde, Dec 13
“All 196 parties unanimously adopt the Paris Agreement after…”
- Paris Agreement adopted, Dec 12
Day 6707 · April 22, 2016
Agreement opens for signature
Paris Agreement made available for formal signature on Earth Day at UN headquarters; 175 nations sign on opening day.
“Paris Agreement made available for formal signature on…”
- Agreement opens for signature, Apr 22
Day 6903 · November 4, 2016
Paris Agreement enters into force
Agreement becomes legally binding after ratification by 55 parties representing 55% of global greenhouse gas emissions.
“Agreement becomes legally binding after ratification by 55…”
- Paris Agreement enters into force, Nov 4
Day 7112 · June 1, 2017
US withdraws (Trump administration)
President Trump announces US withdrawal from Paris Agreement, claiming it disadvantages American workers.
“President Trump announces US withdrawal from Paris…”
- US withdraws (Trump administration), Jun 1
Day 8441 · January 20, 2021
US rejoins Paris Agreement
President Biden rejoins the Paris Agreement on first day in office; formal re-entry takes effect 30 days later.
“President Biden rejoins the Paris Agreement on first day in…”
- US rejoins Paris Agreement, Jan 20
The numbers.
3 numbers that anchor the scale.
By the numbers
The countable parts.
Nations negotiating
0 parties
Current signatories (as of Jan 2026)
0 nations
Climate finance commitment
$0 billion annually from developed nations
Front pages.
3 outlets carried the story: The New York Times, BBC News, Le Monde.
Media coverage
What the world was reading.
5 pieces, ranked by how much they shaped the discourse.
The New York Times
Newspaper · United States · Dec 13, 2015
"Nearly Every Nation Endorses Landmark Climate Accord"
Nearly 200 nations agreed on Saturday to a sweeping climate accord that aims to steeply cut greenhouse gas emissions, the culmination of two decades of international climate negotiations. The landmark deal, reached after two weeks of intense talks near Paris, represents an unprecedented global commitment to fighting climate change.
- Dec 12, 2015
BBC News
TV · United Kingdom
"World Reaches Historic Climate Deal in Paris"
Nearly 200 countries have agreed to cut carbon emissions in an attempt to limit global temperature rises. The Paris climate accord is seen as a historic breakthrough after decades of failed negotiations on how to tackle rising greenhouse gas levels.
- Dec 12, 2015
Reuters
Newspaper · Global
"Nations Reach Historic Climate Deal in Paris"
Nearly 200 countries struck a landmark accord on Saturday that aims to curb greenhouse gases from 2020, marking a watershed moment after 20 years of climate negotiations. The agreement includes the first binding commitment from major emitters including China and the United States.
- Dec 13, 2015
Le Monde
Newspaper · France
"L'accord historique de Paris sur le climat est une victoire pour la planete"
FR: 'L'accord historique de Paris sur le climat est une victoire pour la planete' / EN: 'Paris historic climate accord is a victory for the planet.' - France's leading daily hailed the deal reached on its soil as a transformative moment in international environmental governance, with binding commitments from all major economies.
- Dec 12, 2015
The Guardian
Newspaper · United Kingdom
"The World Has Finally Agreed to Take Climate Change Seriously"
After two decades of failed climate talks, nations have agreed a landmark accord in Paris that commits signatories to keeping global temperature rise well below 2C. The deal includes binding pledges on emissions cuts and climate finance for developing nations.
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Sources & citations.
Sources
Where this came from.
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Wikipedia
1 source- 1.Paris Climate Agreement
en.wikipedia.org