President Obama chats with Indian Prime Minister Narendra Modi, left, as they and other leaders arrive at a hotel in Hangzhou, China, last month. (Ng Han Guan/AP)

The Paris climate agreement, the world’s strongest effort yet to try to curb the pace of climate change, sped even closer toward becoming active as India, the planet’s fourth-largest emitter of greenhouse gases, formally joined the accord Sunday.

The agreement, which 195 countries negotiated over two weeks in December, “enters into force” when at least 55 of them representing 55 percent of global emissions, officially join the accord. For each, that process includes signing and domestically ratifying or otherwise accepting the agreement, and then depositing an “instrument of ratification” at the United Nations. It’s that last step that India completed Sunday.

President Trump has decided to pull the U.S. out of the Paris Agreement. Here's what you need to know. (Daron Taylor/The Washington Post)

“Care & concern towards nature is integral to the Indian ethos,” Prime Minister Narendra Modi tweeted late in the day. “India is committed to doing everything possible to mitigate climate change.”

Major emitters such as the United States, China and Brazil have led the way in joining the agreement, as have dozens of smaller countries. Sunday’s action by India, which emits 4.1 percent of global emissions, brings the agreement to the brink of activation. Sixty-two countries have now joined, representing 51.89 percent of global emissions, according to the United Nations’ Framework Convention on Climate Change.

“Today the government of India has demonstrated global leadership and vision by joining the Paris agreement on climate change,” U.N. Secretary General Ban Ki-moon said Sunday in a statement. “This historic step will further India’s sustainable path to growth and development.”

The ratification came on the birthday of Mohandas Karamchand Gandhi, the Indian independence leader better known as Mahatma Gandhi, who was born Oct. 2, 1869.

The largest remaining emitters that have yet to formally join the agreement include Russia (7.5 percent of emissions), Japan (3.79 percent), Canada (1.95 percent), South Korea (1.85 percent), Mexico (1.7 percent), Indonesia (1.49 percent), South Africa (1.46 percent) and Australia (1.46 percent).

But the European Union, with 28 member nations that collectively account for 12.1 percent of the globe’s emissions, could officially make its move as soon next week. E.U. ministers have “approved the ratification of the Paris Agreement by the European Union,” according to a statement Friday. If the European Parliament approves this action, the world will cross the required 55 percent threshold.

“This demonstrates to an even greater degree the broad global support for the Paris agreement and for strong action on climate change. … It adds to what has been global momentum,” David Waskow, director of the international climate initiative at the World Resources Institute, said of India’s step. Modi in particular, Waskow said, “has recognized the ways that climate change can have severe impacts, especially on vulnerable populations.”

Waskow noted that India faces a variety of threats from climate change. It has a long coastline, making it vulnerable to rising sea levels and intensifying storms and flooding. The country has experienced several devastating heat waves in recent years, which have led to deaths and seriously affected agriculture.

Modi is determined to move the country to a broader mix of electrical sources in coming years, namely by ramping up investments in wind and solar power, Waskow said.

“There are still questions how [Indians] will build out their electricity grid and the pace at which they will transition to renewable energy,” Waskow said, “but very clearly they see this as a core element of their energy access strategy.”

Ajay Mathur, director general of the Energy and Resources Institute of New Delhi, said the country’s formally joining the Paris agreement was not guaranteed.

“There were a huge number of fence-sitters within the government saying: ‘This is going to happen in 2020. Why should we take it seriously now?’” Mathur said, adding that others feared “being seen as not being part of the global action, of being left behind.”

He said that Modi deserves credit for pushing the nation to act quickly: “The fact that it has been ratified at this time, this early … speaks of his commitment. If he didn’t want it, it wouldn’t have happened.”

Mathur noted that the government has three initiatives to help achieve its climate goals — a market to balance supply and consumption of electricity, which should be launched next year; a program to enhance the efficiency of the agriculture sector; and a program to spur more efficient technologies in air conditioning, which is critical, given that cooling accounts for half of the growth in new electricity demand.

Although India is the fourth-largest emitter of global greenhouse gases, its ranking actually understates the significance of the country and the future needs of its more than 1 billion people. Electricity demand is poised to skyrocket in coming decades as hundreds of millions receive access to electricity for the first time.

“We think India is moving to the center stage of global energy,” Fatih Birol, executive director of the International Energy Agency, said last year. “All the numbers are indicating that India will be the number one country in terms of coal consumption worldwide. India will be the number one country for oil demand growth worldwide. And India will be the country with more than 20 percent of the solar [power] worldwide.”

Annie Gowen in New Delhi contributed to this report. 

Read more at Energy & Environment:

A key part of Obama’s climate legacy gets its day in court

Why outgoing U.N. chief Ban Ki-moon was willing to bet big on a climate change deal

How Earth itself has dramatically upped the stakes for the Paris climate accord

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