It unfortunately takes a little bit of time, but climate skeptics’ claims that observations don’t support climate model projections aren’t supported as more observations are made of the Earth system. The latest instance: instead of using just climate projections, a pair of researchers have used observations to try to determine whether internal variability (natural year-to-year changes), self-acceleration (positive feedback loops), or external forcing were most the likely drivers of observed sea-ice retreat in the past 30 years.

The takeaway from this research: external forcing (CO2) is shown to be most responsible. This is a good case of how science works: investigate multiple potential causal factors and let the observed data speak for themselves.

California has two nuclear power plants. San Onofre, between Los Angeles and San Diego, has been offline for months as everyone tries to find an excuse for the alarmingly rapid wear on new reactor tubing. (Being shut down, however, did not prevent a fire from breaking out this week when a pipe ruptured and released radioactive steam.)

But as of Thursday, Diablo Canyon, the nuclear plant to the north, is also offline–thanks to. . . uh, salp?

Little more than 13 months after the world’s third major civilian nuclear accident in three decades, it might be surprising to find that one of the words commonly used in context with nuclear power these days is “renaissance.” Though more the product of public relations than real observation, the concept of a “nuclear renaissance” took hold over the last decade purportedly as a response to the rising price of fossil fuels and a growing concern over climate change–and it became so much a part of the lingua franca that even after an earthquake and tsunami triggered the massive crisis at the Fukushima Daiichi nuclear power plant (a crisis that continues to this day), media reports still try to assess how much of a renaissance we will see post-Fukushima, rather than laugh at the idea that a renaissance ever existed.

The recent announcement by the Environmental Protection Agency (EPA) to delay for further study its proposed emission standards for smog and toxic chemicals has been hailed by the Chamber of Commerce and National Association of Manufactures and condemned by both environmental and health advocates.