Palaeoclimate: Linking events across a key climate transition

The Earth experienced a dramatic climate transition some 34 million years ago, when the Antarctic underwent extraordinarily rapid glaciation. A paper in this week's Nature looks into the connection between this glaciation and a deepening of the calcite compensation depth — the ocean depth at which the rate of calcium carbonate input from surface waters equals the rate of dissolution.
Agostino Merico and colleagues used a global model to test competing ideas put forward to explain the events triggering the climate transition.