greenhouse conditions

Before ice first began to form in Antarctica around 34 million years ago, the Earth was a very different place - but then greenhouse conditions swiftly gave way to an icehouse climate, causing the oceans to become less acidic.

Scientists have been piecing together how Earth's changing climate affected ocean chemistry during this period of transition.

Their work sheds light on the links between glaciation and the ocean carbon cycle.

Topics include: imaging of impact strata on Mars' Holden Crater; Eocene-Oligocene conditions leading to the freezing of Antarctica; evidence that liquid water is not responsible for recent changes observed in Martian gullies; new insights into Cretaceous early Albian greenhouse conditions and implications for future atmospheric carbon dioxide levels; new estimates of Earth's copper supply; discovery of large nitrate pools under the Mojave's desert pavement; frequency of magnitude 9 earthquakes; and the pre-Grand Canyon Colorado River.