Diplomats from nearly 200 nations agreed on Saturday to a "historic" agreement to address climate change by transitioning the world's economies away from fossil fuels and toward cleaner forms of energy production in just a few decades.
The agreement comes as 2015 is expected to be the hottest on record and was announced by French Foreign Minister Laurent Fabius to standing applause and whistles from conference participants.
Fabius said the agreement was "ambitious and balanced" and marked a "historic turning point" in efforts to keep global temperature rise to within 2 degrees Celsius (3.6 Fahrenheit) above pre-Industrial Age levels.
It is the first truly global climate agreement that commits both rich and poor nations to addressing climate change, setting out on the long-term goal of eliminating human-caused greenhouse gases by the end of the century.
The pact also establishes a system to encourage nations to voluntary increase their levels of ambition every five years, and aims to send billions of dollars to help poor nations transition to a greener economy and cope with the impacts of climate change, like more frequent and more intense extreme weather events.
US President Barack Obama is scheduled to make a speech on the agreement at 5:30pm Eastern Time.
— The White House (@WhiteHouse) December 12, 2015
Christine Lagarde, Managing Director of the International Monetary Fund, said "governments must now put words into action."
"That is why my key message is to price carbon right and to do it now," she said. "Charging for the emissions of fossil fuels puts in place the needed incentives for low-carbon investments; it also provides revenues to safeguard the poor, reduce debt, and lower the burden of other taxes on households and businesses. We look forward to dialogue on carbon pricing and helping governments put this vital policy into practice."
UN Environment Programme Executive Director Achim Steiner said the agreement is "probably the most important international agreement in history."
"Nations of the world have underlined that climate change is a threat to the security and prosperity of all societies, and can only be addressed through unity of purpose," he said. "A sustainable future benefits all of humanity."
Many environmental groups and organizations seeking to develop cleaner forms of energy heralded the agreement.
Fred Krupp, president of the Environmental Defense Fund, called the agreement a "transformative moment" in addressing the ravages of climate change and developing markets for clean energy production.
"It makes a moral call for dramatic action that leaves no one behind, and moves us closer to the crucial turning point when global carbon emissions, which have been rising for more than two centuries, finally begin to decline," he said.
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