Like sparring siblings, China and the United States -- the world’s two biggest carbon dioxide emitters -- keep passing the climate-action buck back and forth: “Why should I cut emissions if they don’t have to?” Well, China is either the more mature of the pair, or just majorly sucking up to Mama Earth. The country is reportedly gearing up to set firm limits on greenhouse-gas emissions, seriously weakening one of the U.S.’s go-to excuses for climate inaction.

China's powerful National Development and Reform Commission has proposed an absolute cap on emissions starting in 2016. The proposal still needs to be accepted by the Chinese cabinet, but experts say the commission’s influence makes it likely to pass. China today also announced the details of trial carbon-trading programs that will roll out in seven regions by 2014. In February, the country had said it would implement a carbon tax, but backed off a few weeks later, saying it will wait until early next year to get started on that.

The commission’s carbon-cap proposal calls for Chinese emissions to peak in 2025, five years earlier than previously planned. RenewEconomy explains:

China has already pledged to cut its emissions intensity – the amount of Co2 it emits per economic unit – by up to 45 per cent by 2020. The significance of an absolute cap is that it promises to rein in emissions even if the economy grows faster than expected.

Barack Obama’s advocacy group, Organizing for Action, has been calling out Republican climate skeptics in Congress, but climate activists are not impressed. They're planning to crash OFA events and push the group to fight the Keystone XL pipeline.

350.org and CREDO Action, the political arm of the company CREDO Mobile, are leading the charge. OFA is bracing for it. From BuzzFeed:

OFA circulated a set of talking points to its members for use in dealing with unruly activists. The document, obtained by BuzzFeed, includes information on the science behind climate change and the president’s environmental positions, and ends with a section titled “Keystone Talking Points.” …

"Oops."

Gulf Coast oil refiners and chemical processors say that a lot, but regulators are doing precious little to rein in what the industry euphemistically calls "upset" emissions.

Upset emissions are inadvertent releases of chemicals by industrial operations when something goes awry. And things seem to go awry awfully frequently. An ExxonMobil refinery in Baton Rouge, La., was averaging two accidental releases every week during one grim stretch.

That's according to an analysis by The Center for Public Integrity, which found that upset emissions are more prevalent than industry admits or government knows. Some highlights from the center's investigative report:

Artist Olafur Eliasson has an exhibit about glaciers called Your Waste of Time at MoMA PS1 in New York City. But the exhibit isn't just about glaciers -- it's also made of glaciers. Eliasson broke chunks off Icelandic glaciers and flew them to Queens, which I guess is OK if the point of the exhibit is to make a point about "time that is measured in thousands of years rather than mere decades," as MoMA says, but is kind of ironic if he's trying to make any kind of statement about preserving glaciers.

Solar Impulse, the world's most advanced solar aircraft, is trekking across the United States. It's already made it from the Bay Area to Phoenix, Ariz. Check out photos from its U.S. flights, and read more about the all-solar plane's journey.

Standing beside Solar Impulse -- the world’s most advanced solar aircraft -- in a hangar at the Phoenix Sky Harbor International Airport on a recent afternoon, Bertrand Piccard attempted to diagnose humankind’s biggest problem.

We are being bored to death, he opined.

“People talk about protecting the environment and it’s boring,” the 53-year-old Swiss aviator/psychiatrist said. Discussions about climate change are even worse. "Those," he added, "are boring and depressing."

Piccard’s prescription: Make environmentalism inspiring, exciting, and sexy. Not coincidentally, those adjectives are frequently used to describe Solar Impulse itself, the aircraft Piccard piloted 650 miles, from Mountain View, Calif., to Phoenix, Ariz., on May 3, the first of five legs in a coast-to-coast voyage.

“We want to motivate people to be pioneers,” said Piccard, stressing the syllable with the intensity of a hypnotist (which he is). “We want to show solutions. To show hopes. We want to show what is possible.”

Sen. James Inhofe (R-Okla.) opposed using federal money to help the victims of Superstorm Sandy rebuild their homes, roads, and tattered lives.

That's because he's a fiscal grinch who thinks disaster victims should fend for themselves, Lord of the Flies-style. Right? Well, perhaps not.

Residents of Inhofe's own state are about to receive a bounty of heartfelt help from the federal government in the wake of Monday's epic tornado, which killed at least 24 people and leveled buildings across five counties.

And Inhofe is good with that. He has adopted the very reasonable position that aid money should flow in from federal coffers to help rebuild Oklahoma's shattered neighborhoods.

Canada obviously has a huge stake in the fate of the Keystone XL pipeline. If President Obama fails to approve it -- a decision he recently put off yet again -- the Canadian oil industry will have a tough time getting its abundant tar-sands crude to seaside ports. Prime Minister Stephen Harper recently came to the U.S. to make the case for the pipeline in person, as did Canada's ministers of foreign affairs and natural resources and the premiers of Alberta and Saskatchewan.

And now our neighbor to the north is focusing its powers of persuasion directly on the American people. The country just launched a taxpayer-funded, multimillion-dollar marketing campaign extolling the virtues of tar-sands oil to U.S. citizens. From The Vancouver Observer:

To support the government position and its travelling ministers, Ottawa has launched a $16 million marketing campaign that includes a new website and newspaper advertisements in the US to promote Keystone KL. The thrust of the campaign is the promotion of Canada as a reliable supplier of oil and a “world environmental leader” in the field of oil and gas development.

This tornado, guys. This tornado. I mean. I just. I can't. The whole town! The kids! UGH. I am at the point with national tragedies where I just lose my ability to respond in any coherent way. What do we even DO at that point? Well, one approach is to watch heartwarming animal videos, like this one where a shocked tornado victim discovers during a CBS interview that she didn't lose everything -- she just lost everything except her dog.

It's not just thinking about climate change that can make you feel sick -- climate change itself is bringing maladies upon us. Allergies, fungal infections, malaria, and other health problems are taking a growing toll as the climate shifts — and they are expected to grow worse.

Some members of Congress want the U.S. government to start preparing for these health hazards. On Friday, Rep. Lois Capps (D-Calif.), Rep. Ed Markey (D-Mass.), and two other Democrats in the House introduced the Climate Change Health Protection and Promotion Act, which would authorize the Centers for Disease Control and Prevention to research climate change's health impacts and would help public health officials better plan for the onslaught.