The United Nations climate summit in Dubai was wrapping up last month when John Kerry went to a meeting with his Chinese counterpart Xie Zhenhua only to find a surprise waiting for him. Xie’s 8-year-old grandson had brought Kerry a card for his 80th birthday.

The lanky American, who had signed the landmark Paris climate accord with his own granddaughter on his knee almost a decade earlier, bent down to thank the boy and praise his grandfather, according to someone who described the private encounter on the condition of anonymity.

Just how overheated a planet those two grandchildren half a world apart will inherit has hinged in part on the unusually warm bond between Kerry and Xie, whose relationship for the past decade and a half helped forge the globe’s stutter-step progress in curbing climate change. Xie, 74, retired in December, and Kerry recently announced that he’s stepping down soon.

It was a partnership that defined one generation’s hopes of saving a future one.

At a glance, the two men make an odd pairing. Xie is balding and bespectacled, with a face as round as Kerry’s is narrow and angular. Xie got his start in the Chinese countryside during Mao Zedong’s Cultural Revolution before climbing the ranks of the Communist Party in environmental and economic agencies. Kerry is a son of New England privilege and boarding schools who fought in the Vietnam War and later protested against it. He became a politician and a diplomat, marrying into fabulous wealth along the way.

But over the years, Kerry and Xie forged a remarkable level of trust and respect in the world of international climate negotiations. The result was a series of bilateral and multilateral agreements despite rising tensions between the U.S. and China that have even raised fears of war.

Christiana Figueres, a former United Nations climate chief who oversaw the Paris agreement in 2015, said she struggled to think of any parallel in recent history for the rapport between Kerry and Xie in terms of length and impact. She said they “trusted each other, trusted each other’s sincerity, trusted each other’s attempts, each other’s promises."

Before the Paris deal, Earth was on a trajectory for about 3.5 degrees Celsius (6.3 degrees Fahrenheit) of warming over pre-industrial levels, scientists projected. Now Climate Action Tracker projects warming of 2.1 degrees (3.8 degrees Fahrenheit) — if world leaders follow through on their promises, that is.

However, even that level of warming may be catastrophic, and the departures of Kerry and Xie are reshuffling climate diplomacy at a moment when scientists warn that the move toward clean energy is still happening too slowly. Xie’s successor has been named, but it’s unclear what will happen with Kerry’s position.

@JohnKerry and Xie exit roles that defined generation of climate action. #USPoli #China #ClimateDiplomacy #ClimateNegotiations #ClimateAction

Collaboration between the U.S. and China was critical leading up to the Paris summit, when Kerry was secretary of state and Todd Stern was the top U.S. negotiator.

Xie represented China during climate talks, and Stern found him to be a tough yet amenable interlocutor.

“He laughs, he finds things funny, he jokes back at you,” Stern said. “He also gets mad and indignant and all of that.”

In 2014, President Barack Obama traveled to Beijing to announce a surprise bilateral agreement with President Xi Jinping. The U.S. set a more ambitious target for reducing emissions by 2025, while China promised to peak emissions by 2030.

The importance of the deal became evident one month later. International negotiators were in Lima, Peru, to lay the groundwork for Paris, but they kept getting stuck. Figueres said Xie came to her office at 3 a.m. and asked, “can we talk?”

Xie urged Figueres to use the earlier agreement between the U.S. and China to help break the gridlock. She spent the next two hours shuttling between the two countries’ delegations until a deal was reached.

The next year, the Paris summit produced a milestone agreement by obligating all countries to reduce greenhouse gas emissions. It was the relationship with China, Kerry said afterward, that helped “change the paradigm.”

But Donald Trump was elected president in 2016, and he promptly withdrew the U.S. from the Paris agreement after taking office. Kerry and Xie stepped away from government service.

When Joe Biden defeated Trump in 2020, he asked Kerry to serve as special envoy for climate negotiations. China responded by calling Xie out of retirement, which was viewed as a clear signal that Beijing was ready to work together again.

Even with Trump gone, tensions remained. Biden described China as a top foreign policy challenge, and disputes piled up over intellectual property, maritime access in the South China Sea and the future of Taiwan.

“These kind of things complicate the conversation,” said Jonathan Pershing, who worked for Kerry then and is now the environment program director at the William and Flora Hewlett Foundation. (The foundation also supports The Associated Press’ coverage of climate change.) Kerry and Xie stayed in touch informally even after Beijing cut off communications with the U.S. after then-House Speaker Nancy Pelosi visited Taiwan in 2022. Although the island governs itself as a democracy, China views it as part of its territory.

“They obviously didn’t agree a lot of the time,” said John Podesta, a climate policy veteran who works in the White House. “You could only take a personal relationship so far.”

However, Podesta said, “having that level of trust and dialogue was important.”

Their work culminated in November, when Kerry and Xie met at the Sunnylands resort in California. China agreed to include methane, a particularly potent greenhouse gas, as part of its emissions target.

The next month was their final U.N. summit in Dubai, which ended with a global agreement to transition away from fossil fuels. When the negotiations were over, Kerry and Xie held a joint press conference.

Mentioning his grandson, Xie said he hoped “this cause will be carried forward, generation after generation.” Kerry said how impressive the young boy had been — “unbelievable, he’s great.”

It was the last public moment for the two grandfathers together.

The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content.

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