It's not clear yet what the management shake-ups at General Motors this week, which sent the CEO, Fritz Henderson, packing and shuffled around senior management, will mean for the Chevrolet Volt, the much hyped electric vehicle (with a gas engine for added range) due out next year.

Fans of the Volt--which is also called a plug-in hybrid--have been nervous about its fate ever since an Obama administration commissioned report in March said the vehicle isn't likely to be an economic success. The car is likely to be too expensive, it said, which is due to its large battery pack. Fans have got more reason to worry now that the man the federal government appointed as chairman of GM, Edward Whitacre, is taking over as CEO. Although he says he's taken the position temporarily, his move puts him in a better position to influence day to day operations and decisions about products. That could hurt the Volt if he agrees with the government report.

Since last March, when the government bought a 61 percent share of the company, GM executives have repeatedly said the Volt program will continue, and that the car will come out on time. This week, after Henderson got the axe, it stuck to that story at the L.A. auto show, with vice chairman Robert Lutz highlighting progress on the Volt in a keynote speech. But since then Whitacre has started to make major changes to GM management. It's unclear what the company will look like when the dust settles.

U.S. President Barack Obama and President Hu Jintao of China have announced several agreements for the two countries to cooperate on clean energy. The deals could help smooth the way to a climate change agreement in which both countries agree to reduce greenhouse gas emissions.

China has been dragging its heels over strict cuts in greenhouse gas emissions, especially with the U.S. also so far failing to commit to such cuts. But if China doesn't cut its emissions it will be impossible to meet goals for averting dangerous climate change.

One thing that could help--reduce emissions and convince China to agree to cuts--is sharing the latest technology with China, especially technology for making cleaner power plants. The agreements seem to be a step in that direction.

One deal in particular seems promising. Scientists from both countries will cooperate on developing cleaner coal plants through a new U.S.-China Clean Energy Research Center, which will be jointly funded with $150 million. What's more, a number of U.S. and Chinese corporations have agreed to cooperate, including Peabody Energy, which will help with a project celled GreenGen, and GE Energy, which will help with coal gasification. Both projects could lead to cleaner coal plants that could be paired with technology to capture and sequester carbon dioxide.

Other significant agreements include one to develop natural gas resources, which could reduce greenhouse emissions because burning natural gas releases about half the carbon dioxide as burning coal. Another aims to improve the efficiency of buildings, industry, and consumer appliances. To address growing emissions from cars, both countries will work together to establish standards and roadmaps for the development of electric vehicles.

Today President Obama said that climate change skeptics are being pushed to the margins, but that may have been wishful thinking.

Poll results from the Pew Research Center for the People and the Press released yesterday say that the number of people who believe "there is solid evidence that the earth is warming" dropped from 71 percent in April of 2008 to 57 percent now. Only 36 percent said there was good evidence warming is due to human activity, down from 47 percent in April of 2008. Only 35 percent say climate change is a serious problem.

The numbers of climate change believers have been declining for the last few years among Democrats, Independents and Republicans. For independents, for example, 79 percent believed there was solid evidence in 2006, compared to 53 percent now. It might not be a coincidence that Al Gore's film, "An Inconvenient Truth," came out in 2006.

Now here's the really odd thing. In spite of these low numbers, 50 percent of Americans believe there should be limits on carbon emissions, even if this causes energy prices to rise. Only 39 percent oppose it.

There's an uncharitable interpretation--that Americans are being inconsistent. But there's also a more hopeful interpretation. Climate change models are full of uncertainties. No one really knows just how much the Earth will warm, or what impact this will have, particularly on regional weather patterns. Maybe Americans are learning about these uncertainties, hence the lower numbers siting "solid evidence," yet concluding that the risk is high enough that we should do something to avoid the worst possible scenarios.