Delegates from 196 nations approved a historic climate deal after 13 days of negotiating on Saturday, Dec. 12. Here's what you need to know about the accord. (Video: Monica Akhtar/The Washington Post)

LE BOURGET, France — Negotiators from 196 countries approved a landmark climate accord on Saturday that seeks to dramatically reduce emissions of the greenhouse gases blamed for a dangerous warming of the planet.

The agreement, adopted after 13 days of intense bargaining in a Paris suburb, puts the world’s nations on a course that could fundamentally change the way energy is produced and consumed, gradually reducing reliance on fossil fuels in favor of cleaner forms of energy.

Read the text of the draft climate agreement here.

“History will remember this day,” U.N. Secretary-General Ban Ki-moon said after the pact was gaveled through to thunderous applause. “The Paris agreement on climate change is a monumental success for the planet and its people.”

The deal was struck in a rare show of near-universal accord, as poor and wealthy nations from across the political and geographic spectrum expressed support for measures that require all to take steps to battle climate change. The agreement binds together pledges by individual nations to cut or limit emissions from fossil-fuel burning, within a framework of rules that provide for monitoring and verification as well as financial and technical assistance for developing countries.

The overarching goal is to bring down pollution levels so that the rise in global temperatures is limited to no more than 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial averages. Delegates added language that expressed an ambition to restrict the temperature increase even further, to 1.5 degrees C,  if possible.

Humans’ staggering effect on Earth

“If our species had started with just two people at the time of the earliest agricultural practices some 10,000 years ago, and increased by 1 percent per year, today humanity would be a solid ball of flesh many thousand light years in diameter, and expanding with a radial velocity that, neglecting relativity, would be many times faster than the speed of light.” —Gabor Zovanyi Sprawling Mexico City, Mexico, population 20 million, density 24,600/mile (63,700/square kilometer), rolls across the landscape, displacing every scrap of natural habitat; © Pablo Lopez Luz (Pablo Lopez Luz)

French Foreign Minister Laurent Fabius, who presided over the talks, hailed the pact as a “historical turning point” that could spare the planet’s 7.3 billion people from the most disruptive effects of global warming in decades to come. Before the vote, he urged delegates not to shirk from taking steps that could avert an environmental disaster.

“The citizens of the world – our own citizens – and our children would not understand it. Nor, I believe, would they forgive us,” Fabius said.

Cheers echoed up and down the tent city where thousands of journalists, activists and business leaders awaited news of the deal, which was sealed during the final 48 hours of nearly non-stop talks.

196 countries just agreed to a historic climate deal. Here’s what happens next.

“This is a tremendous victory for all of our citizens–not for any one country or bloc, but a victory for all of the planet, and for future generations,” Secretary of State John F. Kerry said after the accord was announced. “The world has come together behind an agreement that will empower us to chart a new path for our planet: a smart and responsible path, a sustainable path.”

The accord is the first to call on all nations—rich and poor—to take action to limit emissions of carbon dioxide and other greenhouse gases, with additional reviews required every five years to encourage even deeper pollution cuts. A major goal, officials said, is to spur governments and private industry to rapidly develop new technologies to help solve the climate challenge.

“Markets now have the clear signal to unleash the full force of human ingenuity,” said Ban Ki-moon, who praised the pact as “ambitious, credible, flexible and durable.”

“The work starts tomorrow,” he said.

Ice worlds face extinction in warming planet

The agreement is a major diplomatic achievement for the Obama administration, which has made climate change a signature issue in the face of determined opposition from congressional Republicans, many of whom dispute the scientific consensus that links man-made pollution to the Earth’s recent warming.

President Obama, in an appearance at the White House, hailed the agreement as a “turning point for the world,” adding, “We came together around the strong agreement the world needed. Together we’ve shown what’s possible when the world stands as one.”

Obama helped set the stage for the agreement by forging a deal with China last year to work jointly to scale back emissions from their two countries, the world’s two biggest emitters of greenhouse gases. U.S. officials also helped engineer the accord’s unusual “bottom-up” structure, which, by relying on voluntary pledges to cut emissions, spares the White House from having to seek formal approval from a hostile Congress.

Environmental groups generally praised the accord, though some complained the delegates did not go far enough in helping the world’s poorest countries cope with effects of climate change that already are being felt.

“This is a pivotal moment where nations stepped across political fault lines to collectively face down climate change,” said Lou Leonard, vice president of climate change for the World Wildlife Fund. “For decades, we have heard that large developing nations don’t care about climate change and aren’t acting fast enough. The climate talks in Paris showed us that this false narrative now belongs in the dustbin of history.”

Tiny islands become driving force at Paris climate talks

But others blasted the Obama administration for not seeking a more ambitious treaty.

“The United States has hindered ambition,” said Erich Pica, president of the U.S. chapter of Friends of the Earth, an environmental group. “The result is an agreement that could see low-lying islands and coastlines swallowed up by the sea, and many African lands ravaged by drought.”

There also were signs of future trouble for the agreement from political opponents in Washington. Earlier in the week, Sen. James M. Inhofe (R-Okla.), the chairman of the Senate Environment and Public Works Committee, pronounced the Paris talks “full of hot air” and vowed to block the White House from using taxpayer funds to help carry out the accord.

On Saturday, Inhofe said, “The news remains the same. This agreement is no more binding than any other ‘agreement’ from any Conference of the Parties over the last 21 years. Senate leadership has already been outspoken in its positions that the United States is not legally bound to any agreement setting emissions targets or any financial commitment to it without approval by Congress.”

But Kerry told journalists that the agreement would survive Republican opposition and he called on Americans to elect as their next president a candidate who would support strong action on climate change.

“I regret to say, Sen. Inhofe is just wrong: This has to happen,” Kerry told reporters. He added: “I just personally do not believe that any person who doesn’t understand this science and isn’t prepared to do for the next generations what we did here today, and follow through on it, cannot and will not be elected president of the United States. It’s that simple.”

Obama made a strong defense against critics who said that the use of renewable energy would be expensive and destroy jobs. “The skeptics said these actions would kill jobs,” he said. “Instead, we’ve seen the longest streak of job creation in our history,” with renewable projects creating “a steady stream of middle-class jobs.”

Among those witnessing the final approval was former Vice President Al Gore, who had pressed for two decades for a climate deal.

“Years from now, our grandchildren will reflect on humanity’s moral courage to solve the climate crisis and they will look to December 12, 2015, as the day when the community of nations finally made the decision to act,” Gore said. “This universal and ambitious agreement sends a clear signal to governments, businesses, and investors everywhere: the transformation of our global economy from one fueled by dirty energy to one fueled by sustainable economic growth is now firmly and inevitably underway.”

Officials acknowledged that the compromise accord is insufficient, by itself, to prevent global temperatures from rising by more than 2 degrees C above pre-industrial averages, an increase that many scientists believe is the maximum amount of warming the planet can sustain without massive disruptions in natural ecosystems. But the treaty is structured to allow nations to adopt more ambitious cuts in emissions as new technology becomes available.

“There is an ambitious but necessary long-term objective,” Fabius said.

“The reduction of greenhouse gases has become the business of all.”

Immediately after 196 countries approved a historic climate agreement in Paris, Secretary of State John Kerry spoke on behalf of the U.S. and praised the global commitment, but said it is "what we do next" that truly determines how we address climate change. (Video: Reuters)

Carol Morello in Paris contributed to this report.

More at Energy & Environment:

5 things you should know about the historic climate agreement

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Holding warming under two degrees Celsius is the goal. But is it really attainable?

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