The U.S. has officially rejoined the Paris climate agreement

The United States officially rejoined the Paris climate agreement Friday, fulfilling a campaign promise President Joe Biden initiated on his first day in office. Welcoming the nation's official return to the landmark global climate accord, world leaders said that they expect the U.S. to prove its seriousness after four years of being mostly absent. According to The Guardian, the other countries in the pact are particularly keen to hear an announcement from Washington in the coming months on the U.S.'s goal for cutting emissions of heat-trapping gases by the year 2030. The U.S. spent 107 days outside the Paris Agreement after former President Donald Trump completed the three-year withdrawal process on November 4, 2020, one day after the presidential election.

Meanwhile, speaking to members of America Is All In — a coalition of states, cities, private businesses, and other groups led by Mike Bloomberg to keep the U.S. on track to meet its Paris climate goals — President Biden's special presidential envoy for climate change, John Kerry, emphasized the need for urgent and ambitious action. According to ABC News, blaming the Trump administration for being "inexcusably absent for four years," Kerry said: "A lot of us thought that the failure of this enterprise might rest on one word. The word was Trump."

Kerry warned that the world is "not close to where we need to be," partly because the U.S. hadn't stepped up to lead. "Three years later, three years wasted," he said. "Around 2030 is the date in which we have to get the world now on the right path in order to cap the warming at that level of 1.5 [degrees Celsius]. So we are absolutely, clearly, without question inside the decisive decade... it's what people will do in the next 10 years that matter." He stressed that climate change is a "threat multiplier" which is already causing displacement and mass migration, conflict, and humanitarian crises.

"When tensions are already high somewhere and resources are increasingly scarce, the embers of conflict just burn brighter," said Kerry. "And when farmers can no longer make a living because the weather is so extreme and unpredictable, they become increasingly desperate. Many, according to some studies, hundreds of millions, will be forced from their homes... if it is not managed well, it can literally begin to undermine countries, homes, peace, and stability." He also tied the Texas winter storm and the ensuing crisis to climate change, saying: "This week in the state of Texas, we've seen unprecedented extreme cold-related to climate because the polar vortex penetrates further south because of the weakening of the jet stream related to warming."

The world's 17 major economies and biggest emitting countries must take note of "the plight of the people who are the victims," Kerry said. "There's simply no faking it at this moment. Failure is really not an option if we expect to pass the Earth on in the shape that it needs to be to future generations." Christiana Figueres, the former UN climate chief, said that the United States' return to the Paris climate accord sends a strong political message. "From a political symbolism perspective, whether it’s 100 days or four years, it is basically the same thing," Figueres said. "It's not about how many days. It's the political symbolism that the largest economy refuses to see the opportunity of addressing climate change. We've lost too much time."

The UN Environment Programme director, Inger Andersen, said that while the U.S. has to prove its leadership to the rest of the world, she had no doubt that it would when the Biden administration submits its required emissions-cutting targets before a summit in April. "We hope they will translate into a very meaningful reduction of emissions and they will be an example for other countries to follow," Guterres said.