State of the World Population 2009

No. of pages: 104

Publication date: 2009

Author: UNFPA

Climate—the average of weather over time—is always changing, but never in known human experience more dramatically than it is likely to change in the coming century.
For millennia, since civilizations arose from ancient farming societies, the earth’s climate as a whole was relatively stable, with temperatures and patterns of rainfall that have supported human life and its expansion around the globe.