As I mentioned yesterday, a new report from the InterAcademy Council advocates for a price on carbon (among many other things). I started reading it last night, and it's fantastic -- more on it later.

The report was commissioned by China and Brazil. The foreword is by Lu Yongxiang, president of the Chinese Academy of Sciences.

Somehow, our own Charles Komanoff extracts from this slender evidence that "China has put its weight behind a carbon tax -- or a carbon cap-and-trade system that would also impose a carbon price." Next thing you know, Portolio.com says "China approves of cap-and-trade" and Matt Yglesias says "Chinese calls for climate change action."

Whoa now. Slow down.

It's a looong way from a report-in-which-a-government-scientist-is-involved to government-endorsing-report-recommendations, and longer still to government-implementing-report-recommendations. You'll recall that there have been reports popping out of the U.S. government for years warning of the coming disaster of climate change and the need for a concerted response. Bush famously referred to one of them as "the report put out by the bureaucracy." You'll note that nothing has happened as a result.

China has been signaling its concern about climate change for years now. They released a plan to address it in June; they've got emissions cutting programs in place; they've agreed to participate in post-Kyoto negotiations.

Meanwhile, the government has always insisted that any effort to address climate change cannot impact economic growth. It has made a point of chastising the U.S. for hypocrisy. Coal plants are popping up all over the country like mushrooms.

The basic structural problems facing China remain. It's got to keep growing, fast. Coal's the cheapest way to do it. And even when it's willing to impose environmental restrictions, the central government doesn't have all that much control over the provinces.

The bank-shot kinda-endorsement for this report is a positive signal. A system to price carbon that includes developing countries would be an enormous boon to the world. But we're still a long way from China "putting its weight" behind such a system.