A rising population is one of the main reasons that there is global warming. Between 1650 and 1850 the population increased by 0.75 billion people going from 0.25 billion to one billion. From 1930 to the end of the century the population rose from two billion to over six billion. In just a third of the time the population rose by more than five times what it did before. It is expected that this trend in the changing population will continue and could even heighten. The growing population requires increasing amounts of energy. These energy demands and other supplies require production, which almost always involves the emission of greenhouse gases.