Martin Kennedy and colleagues searched the Australian outback for clues to the transition out of Snowball Earth. The answer, as it turns out, was much closer to home.

Fjords line mountainous continental margins where icesheets and glaciers once stood. A two-dimensional model simulation suggests that fjords can be eroded within one million years, primarily in response to topographic ice steering and erosion from ice discharge. Subsequent glaciers that form on these landscapes are smaller and exhibit greater responses to climate change.

The termination of the Marinoan glaciation 635 million years ago is one of the most spectacular climate change events ever recorded. Methane release from equatorial permafrost might have triggered this global meltdown.

Climate change is already altering our planet's biology, with only life in Antarctica so far spared its influence. That's the conclusion from an analysis of tens of thousands of individual local studies covering shrinking glaciers, changing river flows, melting permafrost, increased coastal erosion, and warming lakes and rivers. The study, published in Nature (DOI: 10.1038/nature06937) this week, is based on more comprehensive data than any previous investigation of the biological effects of climate change.

Significant changes in physical and biological systems are occurring on all continents and in most oceans, with a concentration of available data in Europe and North America. Most of these changes are in the direction expected with warming temperature. Here the authors show that these changes in natural systems since at least 1970 are occurring in regions of observed temperature increases, and that these temperature increases at continental scales cannot be explained by natural climate variations alone.

It has been widely hypothesized that a warmer climate in Greenland would increase the volume of lubricating surface meltwater reaching the ice-bedrock interface, accelerating ice flow and increasing mass loss. We have assembled a data set that provides a synoptic-scale view, spanning ice-sheet to outlet-glacier flow, with which to evaluate this hypothesis.