Governors of 18 U.S. states and two territories urged Congress this week to stop "harmful" Environmental Protection Agency regulation of greenhouse-gas emissions, saying the agency isn't equipped to deal with "the very real potential for economic harm."

The President's Council on Environmental Quality (CEQ) has released three draft National Environmental Policy Act (NEPA) guidance documents on when and how federal agencies must consider greenhouse gas (GHG) emissions and climate change in their analysis of proposed actions; specify when there is a need to monitor environmental mitigation commitments; and clarify use of categorical exclusions. Comments on the draft climate change and mitigation policies are due May 24, 2010. Comments on the draft categorical exclusion policy are due April 9.

Slash-and-burn deforestation accounts for about 15% of global CO2 emissions. Despite activists' efforts, forests have been disappearing at the rate of about 34 million acres a year for the last two decades. Globally, Indonesia and Brazil are the third- and fourth-largest emitters respectively of greenhouse gases, after China and the U.S., because of their breakneck pace of forest destruction. Saving the Amazon, Earth's largest tropical jungle, can be a cheaper and faster way to avoid greenhouse gas emissions than replacing coal-fired power plants with renewable energy or switching to electric cars -- although all such measures are considered necessary by climate experts.

A proposal to cut down hundreds of invasive tamarisk trees in a desert community east of Bakersfield, CA, to build a solar power plant is seen as "a big environmental win" by local officials. Other proposals to build solar farms on hundreds of thousands of acres in the desert Southwest have split the environmental movement and divided local communities. For solar developers and some green groups, the projects are desperately needed in the fight against climate change; others see them as a threat to unique and fragile ecosystems.

Estimates of carbon dioxide emissions from wildfires may be significantly overestimated, a recent Oregon State University study indicates. Even when a very severe fire kills almost all of the trees in a patch, the scientists said, the remaining trees drop to the forest floor, decay, and release their carbon content very slowly over several decades. Timber harvest has much more effect on the amount of carbon in the atmosphere than fire, the researchers said.