President Biden’s climate envoy, John Kerry, traveled to Beijing this week in hopes of persuading officials there to start reducing China’s carbon emissions on a faster timeline. After all, China is responsible for nearly a third of global emissions, and scientists say that its decisions — along with those of the U.S. — will be vital in the fight to stave off the most catastrophic impacts of climate change.

But after three days of talks, Kerry emerged today without any new agreements. In fact, the Chinese president, Xi Jinping, insisted in a speech that China would pursue its goals to phase out carbon dioxide pollution at its own pace and in its own way.

Xi’s comments — which reiterated his plan to make China carbon neutral by 2060, but rejected outside influence — suggested that tensions between the U.S. and China were making it difficult to work together on a crisis that threatens the planet.

Still, Kerry insisted he was not disappointed in the outcome, noting that just talking showed progress. “We had very frank conversations, but we came here to break new ground,” he said, adding, “It is clear that we are going to need a little more work.”

For more: We took a look at how the U.S. and China — the world’s two largest polluters — stack up.

Extreme heat: On Sunday, a remote town in northwestern China reported the highest temperature ever recorded in that country: 126 degrees.

Russia threatened ships headed to Ukraine

Russian forces will consider any ship in the Black Sea bound for Ukrainian ports to be a potential carrier of military cargo, the Kremlin said, in a significant escalation of tension and a blow to Ukraine’s ability to export its grain.

The declaration appeared to signal that Moscow would view commercial ships as legitimate military targets, which will almost certainly deter commercial shipping. The announcement, coming just days after Moscow pulled out of a U.N.-brokered deal that allowed Ukrainian ships to export grain, sent wheat prices skyrocketing.

In other news from the war, the head of Britain’s foreign intelligence agency, MI6, said that Vladimir Putin had cut a deal allowing Yevgeny Prigozhin, the mercenary leader who rebelled last month, to “save his skin.”

Israel’s president addressed Congress at a fraught moment

In a speech to American lawmakers on Capitol Hill, President Isaac Herzog of Israel sought to ease concerns that his country was losing its democratic, pluralistic tradition.

That message appeared to be aimed not just at the U.S., but also at members of Prime Minister Benjamin Netanyahu’s government, who wish to increase the power of Netanyahu’s office. That effort, along with settlement construction in the West Bank, has strained the longstanding bipartisan support from the U.S.

The tensions were clear again today, when a handful of Democrats boycotted the speech, among them Representative Pramila Jayapal, who last week said that Israel “is a racist state” before walking it back.

Stanford’s president will resign

Following a review that found significant flaws in his academic research, Marc Tessier-Lavigne announced today that he would step down as president of Stanford University. Tessier-Lavigne, who will remain at the university as a professor of biology, said he would retract three papers and correct two more. Questions about the accuracy of his work were recently resurfaced by the student newspaper, The Stanford Daily.

In other education news, Wesleyan University, a liberal arts college in Connecticut, said it would no longer give a leg up to the children of alumni.

It’s been a weird summer for many kids

For generations of American children, July has been a time for swimming, exploring, singing, shooting hoops, creating art and making new friends. In other words: camp time.

Unfortunately, the recent stretch of extreme weather has made for many more unhappy campers. First there was the smoke from the Canadian wildfires, which polluted air across the country. Then floods sent children home in the Northeast. And this week, it continued to be too hot for extended outdoor activities across much of the South and West.

No one quite knows what’s causing these space explosions

They are called the Cow, the Koala, the Camel and the Tasmanian devil. But don’t worry — no Earth-dwelling animals were hurt in these gigantic explosions in outer space. Instead, those are simply nicknames given to a weird phenomenon that scientists can’t explain.

The latest, the Finch, was the most intriguing yet: It was found far outside any galaxy, where scientists wouldn’t expect many, if any, stars. The most promising explanation to date is that the explosions are the result of a star 20 times the size of the sun collapsing into a black hole.

Is the Hudson swimmable?

Parts of the Hudson River, which runs from the Adirondacks to New York City, are potentially hazardous for humans, from dumped sewage or leftover mercury. But as a whole, the river is so much cleaner than it was years ago. And one man plans to swim the whole thing to prove it — 315 miles in nothing but a Speedo, a cap and goggles.

That man, Lewis Pugh, is looking to raise awareness about the potential to revive toxic waterways. Pugh knows he might encounter a number of unpleasant obstacles on his journey, but he says he wants to prove to people along the Nile, the Seine or the River Thames that their river, too, can be saved.

Have a hazard-free evening.

Thanks for reading. I’ll be back tomorrow. — Matthew

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