As the US Senate gears up to debate the latest incarnation of proposed climate legislation next week, a blue-ribbon panel has released what it hopes will be a definitive guide to the consequences of climate change for lawmakers and the public. In offering a degree-by-degree breakdown of the potential impacts of temperature change, the report aims to highlight the effects of stabilizing greenhouse gases at a chosen target level.

A 740,000-year-old wedge of ice discovered in central Yukon Territory, Canada, is the oldest known ice in North America. It suggests that permafrost has survived climates warmer than today's, according to a new study.