Coffee (black) was served by Milankovitch’s wife promptly at ten o’clock, and occupied just ten minutes before it was back to work. Lunch at one was followed by a short siesta and a cigar, then more calculations until six, when work ceased for the day. A stroll before dinner, which was a leisurely meal taken at eight, where the family discussed the

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.

The changes resulting from Arctic warming would be bigger than you might expect at first sight, and would in many ways be unpredictable, because of the effect of positive feedback. Today, the shiny white surface of the ice covering the Arctic Ocean reflects away incoming solar energy, and helps to keep the polar region cool. Once the ice starts to

But you can’t have half the north polar icecap; the feedbacks make it an all or nothing choice.

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.

It is concluded that changes in the Earth’s orbital geometry are the fundamental cause of Quaternary ice ages. A model of future climate based on the observed orbital-climate relationships... predicts that the long-term trend over the next several thousand years is towards extensive northern-hemisphere glaciation.

This fact alone tells you that our distance from the Sun is not the cause of the seasons; in the Northern Hemisphere, we have summer when we are furthest from the Sun. But maybe the elliptical orbit produces other, more subtle effects on climate.

Leverrier’s calculations had already shown that whatever kind of orbit the Earth is in at any particular epoch, the amount of heat received from the Sun over the course of an entire year stays the same; but Croll followed up the idea that it might be the way the heat is distributed between the seasons which matters, since this is undoubtedly

when more water is locked up in ice, the sea level falls; but when the ice sheets melt, sea level rises.