Climate Change by Numbers

There are tipping points, our next door neighbour Venus shows us that quite clearly, also it is now thought that we live a lot closer to the inner edge of the goldilocks zone than we imagined, there is no guarantee that if we pass a certain point in terms of carbon in the atmosphere that we will ever get another glacial period.

As our star gets older it gets hotter, the sun put out a lot less energy when it was young of the order of 25% less, we will be in the habitable zone for a lot less than the 5 billion years our star has left.