From Hothouse to Icehouse

Sediment cores from more temperate oceans tell us how Earth's climate developed. At the beginning of the Eocene Epoch (55 - 34 million years ago) extremely warm hothouse conditions prevailed. Unlike today, the poles and continents were ice-free. Cooling occurred during the Eocene, and the first Antarctic ice sheets began to develop around 34 million years ago. Will the Lomonosov cores confirm this story, and add to it?

The cooling trend wasn't constant. Superimposed were shorter-term climate fluctuations such as the ice ages, which began about 2.7 million years ago and persist to today. Now, we are in an unusually warm "interglacial" period. Will we return to another ice age, which has a periodicity of about 100,000 years, or will the climate continue to warm?

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