Hong Kong CNN — As John Kerry arrived in Beijing Sunday for a long-awaited trip to restart climate negotiations, the US climate envoy stepped off the plane into one of the hottest summers ever recorded in the Chinese capital.

Since 1951, Beijing has seen temperatures breaching 104 degrees Fahrenheit (40 degrees Celsius) on 11 days — with almost half of them occurring in the past few weeks, including a new record for the city’s hottest day in June.

In the United States, an extreme heat wave is also swelling, with temperatures in the Southwest soaring as high as 120°F (49°C).

It’s a global problem: the planet’s hottest day ever was recorded for four straight days earlier this month.

“If anything, this is the situation that should most bring China and the US back on the same page,” said Li Shuo, senior global policy adviser at Greenpeace China.

“Regardless of their political differences, the impacts of climate change have now become a common experience for both countries — it’s no longer a hypothetical crisis or analytical challenge, but a living reality that can be felt through the skin.”

As the world’s two biggest polluters — with China’s emissions of planet-heating pollution more than double those of the US — the two countries account for nearly 40% of global emissions.