After more than two decades of fraught negotiations, delegates from nearly 200 countries have agreed to a historic deal to steer the world away from catastrophic climate change, signalling the end of the fossil fuel era.
The Paris deal on Saturday is a vote of support for renewable energy as well as for more efficient buildings and transport, and a decisive shift away from coal, oil and gas, which are driving climate change.
With this year set to be the hottest on record, a pact that commits all countries to curb carbon pollution has become urgent to try to limit escalating damage from weather extremes and rising seas.
World leaders hailed the agreement, saying it was the best chance to secure the planet's future.
"We don't have a perfect agreement, but we have a good and necessary agreement. This historic agreement sets us on a collective journey for climate safety," said Minister for Foreign Affairs and head of the Singapore delegation in Paris, Dr Vivian Balakrishnan, who played a key role in guiding the negotiations.
Deputy Prime Minister Teo Chee Hean, who chairs the Inter-Ministerial Committee on Climate Change, said the pact was a showcase for international cooperation.
"The agreement shows how, with goodwill, commitment and willingness to look beyond individual concerns, cooperation among all countries is possible for the global larger, long-term good," he said in a statement. "We are honoured that Singapore has contributed to the success of the talks."
President Barack Obama said the United States should be proud of the agreement, but also warned that there was a long way to go in preventing warming that scientists say will fuel far more extreme droughts, floods, heatwaves and quickly rising seas. China and India, the world's No. 1 and No. 3 greenhouse gas polluters, also welcomed the Paris agreement.
Vulnerable small islands fought hard to ensure the deal was ambitious, with many islands in the Caribbean and Pacific and Indian oceans already battered by higher seas.
The deal aims to hold global warming to well below 2 deg C and for nations to pursue actions to limit the warming to 1.5 deg C.
The agreement does not immediately solve the threat from climate change. Temperatures and emissions are still rising and the climate action plans that nearly 190 nations submitted ahead of the talks put the world on a path to warm by nearly 3 deg C, a level that would trigger deadly climate change.
Instead, the pact covers all nations, rich or poor, and creates a long-term blueprint in which countries are committed to making progressively deeper emission cuts.
After Paris, all nations must now quickly enact their action plans and be transparent about them.
Underscoring the financial challenge, and opportunities, the targets outlined in the deal will need US$16.5 trillion (S$23.3 trillion) of spending in renewable energy and energy efficiency through to 2030, according to the International Energy Agency, Bloomberg reported.
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