PARIS - After more than two decades of fraught negotiations, delegates from nearly 200 nations agreed a historic deal on Saturday to step up global efforts to fight climate change to try to limit escalating damage from weather extremes and rising seas.
It also sets the world on a path to shift away from polluting fossil fuels towards renewable energy as well as more efficient buildings and transport.
Negotiators worked for two weeks at the UN-led talks in Paris, often late into the night, to overcome deep differences.
"The Paris Agreement is adopted," said French Foreign Minister Laurent Fabius, the president of the talks, as he banged down the gavel during the final plenary to huge applause from delegates and throughout the conference venue.
The deal comes at the end of a year that is set to be the hottest on record, marked by historic drought in California, deadly fires in Indonesia and Australia and severe floods in India and Britain.
The talks went 24 hours into extra time as negotiators overcame issues over financing for poorer nations and how to transparently review and ratchet up national plans to cut greenhouse gas emissions blamed for heating up the planet.
South Africa, representing the G-77, which groups 134 developing countries, said the text was not perfect.
"But we believe that it represents a solid foundation from which we can launch our enhanced action with renewed determination. It is our view that the agreement is balanced and the best that we can get at this historic moment," said Ms Bomo Edna Molewa, South Africa's Minister for Water and Environmental Affairs.
The United States also hailed the agreement and said it would unleash the genius of the financial markets in driving climate change investments.
"This is a tremendous victory for all our citizens… for all of the planet and for future generations," said US Secretary of State, Mr John Kerry.
India and China also backed the agreement, with China, as the world's top carbon polluter, pledging to fully implement its climate action plans.
Australia's Foreign Minister, Ms Julie Bishop, speaking for the Umbrella Group of developed nations said: "Today we have created a global agreement. Our work here is done and now we can return home to implement this agreement. The world has come together to capture our common aspirations."
Nicaragua's delegate spoke out against the agreement, saying it wasn't ambitious enough and complained that the pact was adopted before he could speak out.
But his voice was drowned out by the praise in support of the agreement and for the French government, which staked its international reputation in sealing a deal that had eluded the world for more than 20 years.
The deal in Paris also finally casts aside the ghost of the failed 2009 UN climate talks in Copenhagen which was meant to agree on a global climate deal but faltered in the final hours.
The final text contains a goal to limit warming to 1.5 deg C, a victory for vulnerable small island states which demanded that big polluting nations agree on a more ambitious target. It sets out five-year reviews for national climate action plans, a key demand for rich nations. And it also sets out cooperation on loss and damage for poorer states which want assistance for destruction wrought by extreme weather and higher seas.
The global climate deal is basically a new economic blueprint for the planet because it aims to cut greenhouse gas pollution from burning fossil fuels, deforestation and agriculture that is heating up the atmosphere and oceans.
If nations follow through on their climate pledges and steadily increase their emissions cuts, it will mean a transformation of how energy is produced and how efficiently it is used.
A global commitment to cut greenhouse gas emissions will spur deeper investment in renewable energy and drive increased spending on electric vehicles and less polluting shipping and aviation. Buildings will need to become greener, using less energy for lighting, cooling and heating.
The key now is implementing the agreement, which will require all nations to progressively strengthen their climate action plans and submit them for regular reviews.
Nearly 190 nations submitted their climate plans ahead of the Paris talks in widespread acceptance of the goal to get all countries on board, while respecting differences in national circumstances.
While the framework for the review and ratchet-up mechanism has been agreed, more work will be needed to flesh out the process to ensure all countries deepen their emissions cuts and investments in cleaner energy and energy efficiency measures.
