Prediction is always a risky business, but some things are actually quite predictable, while others are less so. Natural cycles such as the seasons will continue, although human-caused global warming may be changing them to some extent. Human demographic processes are fairly predictable as well. Because of the spread of the demographic transition (to lower birthrates) in the Global South, demographers predict that the total population of the earth will peak around 2075. The steepness and duration of this continuing rise will determine how many people will eventually be on earth-estimates vary from 10 billion to 12 billion. The timing and height will be affected by the usual factors: food supply, diseases, and natural and human-caused disasters. The education of women and their employment in jobs outside the home are the main things that affect the demographic transition. Its rapidity or slowness and the consequent eventual size of the global population will have a huge impact

on the effort to move toward a more sustainable global economy. The fewer humans that need to be accommodated, the easier the required adjustments will be.1