Ice Age

As a reservist with the Serbian army, he was imprisoned at Esseg, an experience which he later described in graphic terms: The heavy iron door was closed behind me. The massive rusty lock gave a rumbling moan when the key was turned... I adjusted to my new situation by switching off my brain and staring apathetically into the air. After a while I h

The distinguishing characteristic of human beings is versatility. Some animals run faster, some are better swimmers, some have better teeth and claws for killing and eating meat, some have better teeth and digestive systems for eating plants, and so on. But people do a little bit of everything quite well.

Layer by layer, the mud of the sea bed builds up, and each layer contains the remains of the creatures best suited to the climate at the time that layer was being laid down.

The change in eccentricity is measured in terms of the distance between the two foci of the ellipse, as a percentage of the long axis of the ellipse. For a perfect circle, the two foci merge to become one, with no distance between them, so the eccentricity is zero. Today, the eccentricity of the Earth’s orbit is about 1 per cent, but Leverrier show

Kukla had not invented this technique, although he was one of the first people to apply it to the study of past climates. It depended upon the discovery that the Earth’s magnetic field is not constant, but sometimes (seemingly at random) reverses itself entirely, first fading away to nothing and then building up again in the opposite sense, so that

He was one of the first people to appreciate the major influence of the great ocean currents on climate, and was the first person to work out the link between the trade winds (essentially driven by convection in the atmosphere stirred up by the Sun heating the surface of the Earth) and the flow of these currents, pushed by the winds. He reasoned th

The best place to find out what the climate of the Earth was like in the past is at the bottom of the deep ocean.

Milankovitch reckoned that he started out on the task, when he was thirty-two years old, at exactly the right time: Had I been somewhat younger I would not have possessed the necessary knowledge and experience... Had I been older I would not have had enough of that self-confidence that only youth can offer.

When reversals happen, they take place in less than 10,000 years (perhaps much less), so they show up sharply in the geological record; but once a particular orientation of the field is established, it may last for millions of years, or only for a few tens of thousands of years. The most recent reversal happened about 780,000 years ago, but the Ear